FAQ

Q1

Points on connecting wires used in power supplies?

Ans

To install a power supply into the system, you would need wires for the connection both to the loads and to the energy source. There are a couple of points that should be taken into consideration when choosing wires, one is current rating, it may cause high heat on the wires or burnt out in the worst case, if the rating is not enough. The other is voltage drop, there would be voltage reduction at load side as current moves through the wires owing to the internal resistance. If too much voltage drop in line, there could be no sufficient voltage to drive the loads. You can find the right wires for use by referring to the table below on the basis of your system design.

Q2

Why the input voltage marked on the spec. sheet is 88~264 VAC while the label on the power supply says that it is 100~240VAC?

Ans

During safety verification process, the agency will use a stricter standard ±10% (IEC 62368 uses +10%, -10% for the product with AC input rated) of the input voltage range labeled on the power supply to conduct the test. So, operating at the wider input voltage range as specified on the spec. sheet should be fine. The narrower range of input voltage labeled on the power supply is to fulfill the test standard of safety regulation and make sure that users insert input voltage correctly.

Q3

Notes on choosing a switching power supply?

Ans

  1. To increase the reliability of the S.P.S., we suggest users choose a unit that has a rating of 30% more power than actual need. For example, if the system needs a 100W source, we suggest that users choose a S.P.S. with 130W of output power or more. By doing this, you can effectively boost the reliability of the S.P.S. in your system.
  2. We also need to consider about ambient temperature of the S.P.S. and whether there is additional device for dissipating the heat. If the S.P.S. is working in a high temperature environment, we need to make some derating to the output power. The derating curve of "ambient temperature" versus "output power" can be found on our spec sheets.
  3. Choosing functions based on your application:
  • Protection function: Over Voltage Protection (OVP), Over Temperature Protection (OVP), Over Load Protection (OLP), and etc.
  • Application function: Signaling Function (Power Good, Power Fail), Remote Control, Remote Sensing, and etc.
  • Special function: Power Factor Correction (PFC), Uninterruptible Power Supply (UPS) function.

     4.   Make sure that the model qualifies for the safety standards and EMC regulations you need.

Q4

What are the intelligent products of MEAN WELL?

Ans

MEAN WELL intelligent products are those equipped with communication interfaces, parameters and functionality can be adjusted or changed via the interfaces. Take the RPB-1600, the intelligent battery charger as an example, users can easily adjust charge curves to deal with various types of batteries owing to its PMBus communication protocol. Mean Well divides the intelligent products into four sections: PMBus, CAN bus, DALI, DALI-2 and KNX. Please read the following for more information.
 
>> PMBus


PMBus stands for Power Management Bus, which is an open standard power-management protocol, featuring flexibility and highly versatile standard. Those intelligent products with the protocol are able to do parameter settings, such as output voltage/current, status reports, etc. The models are as below:
RCP-2000
RCP/RPB/RCB-1600
RSP-1600PM
DRP/DBR/DBU-3200
DPU-3200PM
PHP-3500
UHP-1500/2500
HEP-1000
HEP-2300PM
SHP-10KPM
CMU2C-P
 
>>CAN bus
The Controller Area Network bus is a serial communication bus designed for robust and flexible performance. Those intelligent products with the protocol are able to do parameter settings, such as output voltage/current, status reports, etc. The models are as below:
RSP/RCP/RPB/RCB-1600CN
DPU/DRP/DBU/DBR-3200CN
PHP-3500CN
UHP-1500CN/2500CN
HEP-1000CN
HEP-2300
SHP-10K
DRS-240CAN/480CAN
CMU2C-C

>>Modbus
Modbus is a data communications protocol that was originally designed for PLCs. There are many variants of Modbus protocols, MEAN WELL selected Modbus RTU (Remote Terminal Unit) with EIA-485 because of advantages of robust and flexible performance. Those intelligent products with the protocol are able to do parameter settings, such as output voltage/current, status reports, etc. The models are as below:
HEP-2300MOD
SHP-10KMOD
DRS-240/480
 
>>DALI
DALI stands for Digital Addressable Lighting Interface, a digital, internationally adopted language used to control lighting such as LED Drivers. Those products/drivers with the protocol are able to cooperate with DALI controller to form smart luminaires for interior use. The models are as below:
LCM-25DA/40DA/60DA
LCM-40UDA/60UDA
ELG-75CDA/100CDA/150CDA/200CDA/240CDA
ELG-75DA/100DA/150DA/200DA/240DA
HLG-320-CDA
HBG-100DA/160DA/200DA/240DA
HBC-100PDA/160PDA
HVGC-480ADA/650DA
ODLC-45DA/65DA
LDC-35DA/55DA/80DA
PWM-60DA/90DA/120DA
IDLC-45DA/65DA
IDPC-45DA/65DA
DAP-04
LDD-H-DA
 
>>DALI-2
DALI-2 is an updated version of DALI. The main difference for DALI-2 is that specification of electrical tolerances is more precise and it added new commands, such as extended fade-time, making fades from 0.1 seconds up to 16 minutes. DALI-2 products/drivers not only can work with DALI-2 application controllers and input devices, but also can be installed into DALI system. The models are as below:
LCM-25DA2/40DA2/60DA2
PWM-60DA2/90DA2/120DA2/200DA2
ELGC-300-L/M/H-ADA
HBGC-300-L/M/H-ADA
HVGC-1000-L/M/H-DA
LDC-55DA2
LCM-40TW
DLC-02
 
>>KNX
KNX is an open standard for commercial and domestic building automation. It controls all aspects of home and building control such as: lighting, heating, cooling and ventilation, blinds/ shutters. Those products/drivers with the protocol are able to cooperate with KNX controllers and switches to form small home network or being installed into smart commercial building. The models are as below:
LCM-25KN/40KN/60KN
PWM-60KN/120KN
KAA-8R(-10)
KAA-4R4V(-10)
KDA-64
KNX-40E-1280D
DLC-02KN

Q5

What is a 3+N system solution?

Ans

3 + N system:“3”means Rack Power, Modular Power and System Power and “N”represents infinite possibilities of MEAN WELLs product combination and flexibility, for example: a 3+N system can be 20 units of DRP-3200 + CMU2.
MEAN WELL possesses over ten thousand of standardized power supplies and Professional Technical Service Teams deploy worldwide. Through our Sales and Technical Service Teams, MEAN WELL can provide suitable products and solutions to customers application or even building a customized 3 + N system for the application.

Q6

When a problem occurred, how could I check if power supply is still ok?

Ans

  1. For end users, we suggest applying RMA service from original purchased sales channel.
  2. For skilled technicians or business partners, we suggest doing a standalone power supply test. First, separate power supply unit from the system and then check the no load output voltage. If output voltage is correct, then reinstall the power supply unit to the system and check again the status. If possible, measure the output voltage and current waveform for further analysis.

Q7

How to apply a RMA service?

Ans

  1. To claim a warranty repair service, please prepare necessary information e.g. product model name, serial number, defective quantity and defect phenomenon description.
  2. Check with your original sales channel for RMA application process.
  3. Note for delivery cost: customer pay for the waybill sending RMA to service center, service center pays for the waybill sending back to the customer.

Q8

What the 3+N system solutions MEAN WELL has provided?

Ans

Currently, MEAN WELL provides:
1.CMU2 power management system solutions
2.System power solutions
 
3.High voltage DC LED lighting control solutions
 
4.IOT wireless LED lighting control solutions

5.DALI smart LED lighting control solutions
 
6.KNX building automation control solution
 
7.Burn-in power recycling  
MEAN WELL can customize a solution suitable for your applications. If you have questions or inquiries, please feel free to contact us.

Q9

What solution and products does MEAN WELL provide for building automation?

Ans

For Building automation, MEAN WELL utilizes KNX as the solution. Please refer to the KNX building automation website for detailed information and relevant applications.
http://building.meanwell.com.tw/
   

Q10

Will MEAN WELL's products with CE marking meet the EMC requirements after assembling into my system?

Ans

We cannot guarantee 100% that the final system can still meet the EMC requirements. The location, wiring and grounding of the switching power supply in the system may influence its EMC characteristics. In different environment or applications, the same switching power supply may have different outcomes. Our test results are based on setup shown in the EMC report.

Q11

How to select adaptors with the correct AC plug for use in different countries?

Ans

An adaptor may need connection of a power cord to receive energy needed from the utility. You can refer to the specification of the adaptor for the connector (AC inlet) at the adaptor end of the power cord; Different countries/regions vary in type of AC socket and voltage, please look at the table below for the information of the AC plug you need.

Q12

Can MEAN WELL's power supply be used in the range of 45Hz ~ 440Hz? If YES, what will happen?

Ans

MEAN WELL's power supply can be used within this frequency range. But if the frequency is too low, the efficiency will also be lower. For example, when a SP-200-24 is operated under 230VAC and rated load, if the frequency of AC input is 60 Hz, the efficiency is around 84%; however, if the frequency of AC input reduces to 50 Hz, the efficiency will be around 83.8%. If the frequency is too high, the power factor of the S.P.S. with PFC (power factor correction) function will reduce and this also will cause higher leakage current. For example, when a SP-200-24 is operated under 230VAC and rated load, if the frequency of AC input is 60 Hz, the power factor is 0.93 and the leakage current is around 0.7mA; however, if the frequency of AC input increase to 440 Hz, the power factor will decrease to 0.75 and the leakage current will rise to around 4.3mA.

Q13

What is minimum load requirement and how can I read it from the spec?

Ans

There are some minimum-load requirements on MEAN WELL's multi-output power supplies. Please read the specification first before connecting to the load. In order to allow the power supply to work properly, a minimum load for each output is required, or else, the output voltage level will be unstable or outer tolerance range. Please refer to “Current range” in the specification as shown in the table below: Channel 1 requires a 2A minimum-load; channel 2 requires 0.5A; Channel 3 requires 0.1A ; Channel 4 does not need any minimum-load.

Q14

What is ENEC logo? What is the difference between ENEC logo and TUV logo in LED power application?

Ans

ENEC is the European safety standard mark.
The scheme is based on the European full certification scheme of ISO-type5, which was initially established in 1991. There are 24 member certification bodies including TUV, VDE, Demko, Nemko participating in the scheme. At the beginning, it was only applicable to all kinds of lamps and lanterns. With the efforts of European industrial and consumer organizations, the scope of application has covered lighting products and their accessories, switches, controllers, connectors, couplers, plugs, consumer electronic products, audio-visual equipment, information technology equipment, household appliances, safety isolation transformers, electrical appliances, filters and other products. ENEC is a more competitive enterprise High value reliable verification mark. The new generation LED power of MEAN WELL have apllied for the ENEC mark presently. The code of verification unit will be added after the ENEC mark. For example,ENEC05 represents the ENEC logo issued by DEKRA, and ENEC17 represents the ENEC logo issued by TUV RH. The common ENEC codes are as follows.

ID Country CB Acronym ID Country CB Acronym
02 Belgium SGS CEBEC 15 Denmark UL Int DEMKO
05 Netherlands DEKRA 16 Finland SGS FIMKO
12 United Kingdom BSI 17 Norway NEMKO
14 Sweden Intertek Semko 24 Germany TUV Rheinland
 
The difference between ENEC and TUV for LED power supply is that ENEC should also meet the requirements of performance EN 62384 in addition to the safety regulations EN 61347-1 and EN 61347-2-13. For example, LED power supply will require that it should be normally burned for 200 hours under TC environment to ensure the suitability of TC declaration.

Q15

A few things you should know before using the Remote Sensing function

Ans

First, use twisted wires, connect +S to the positive end of the output, then -S to the negative end of the output, as shown in the illustration. Also, keep the wires off the AC and output cables to prevent noise interference.
Add capacitors at output end where the Remote Sensing wires are connected to if dynamic load (frequency above 1K Hz) is used. The purpose is to reduce noise as Remote Sensing is a sensitive function. A suitable capacitor requires two factors:
a. Rated Ripple Current is 0.2 times greater than the output current
b. Rated Voltage is higher than the output voltage

Q16

What solution and products does MEAN WELL provide for wireless lighting control?

Ans

For wireless lighting control, MEAN WELL utilizes Bluetooth low energy Mesh. Currently, there are LCM-IOT and PWM-IOT series in the product line, which can be adopted in applications of constant current and constant voltage control. Please refer to the specifications for detailed information.
 

Q17

What is the difference between 3+N system solutions and previous service methods?

Ans

Being a Leading standard power supply Manufacturer with many different Product Lines, MEAN WELL continues developing more intelligent products with complex functionality suitable for new industries. For the general products, such as enclosed type power supplies and LED drivers, our partners and customers are well familiar with and easy to use. However, for those intelligent products such as KNX, MCU controllers, bidirectional power supplies, etc., our partners and customers may struggle to use. MEAN WELL Technical Service team can actively communicate with customers to understand the application requirements and suggest suitable products and solutions to speed the design-in process allowing MEAN WELL to become multi-industry applications solution Provider.

Q18

Notice on sending an RMA back

Ans

1. Please send the power supply unit only. Do not send system load unless otherwise indicated.
2. Pack the product in a proper way to avoid damage due to transportation.

Q19

If product is defected and not in the original purchasing country, how to get support?

Ans

Please check with your original sale channel for best support. Alternatively, please send your information to local representative offices or distributors for further check.

Q20

For the 3+N system solutions, where can I find more information and how to contact MEAN WELL Technical Service Team?

Ans

We welcome you to download the MEAN WELL app. We provide 3 + N system solutions information from FAQs, Technology News, Technical video and Seminars. If you are a member of the app, you will receive the latest news. The contact information of MEAN WELL Technical Service Team can be found from the link below:
https://expo.meanwell.com/aboutRange.aspx?i=27#A.
Please contact our team member in your region for instant service.

Q21

How many units can be controlled by CASAMBI app?

Ans

It is 125 nodes that can be controlled at a time by CASAMBI app.

Q22

What is class 2, class II and LPS? What is the difference between class I and class II?

Ans

Class I: Equipment where protection against electric shock is achieved by using basic insulation and also providing a means of connecting to the protective earth conductor in the building where by routing those conductive parts that are otherwise capable of assuming hazardous voltages to earth ground if the basic insulation fails. This means a class I SPS will provide a terminal/pin for earth ground connection.

Class II: Equipment in which protection against electric shock does not rely on basic insulation only, but in which additional safety precautions, such as double insulation or reinforced insulation are provided, there being no reliance on either protective earth or installation conditions. This means a class II SPS does NOT have a terminal/pin for earth ground connection.

LPS: When an electronic circuit is powered by a limit power source (LPS), its output current and power are under the limitation shown in IEC 62368-1 Table Q1, and the risk of fire can be reduced significantly. So, the safety distances and flammability rating of components can be much lower. Therefore, the plastic enclosure of these power supplies could use HB flammability rating to reduce cost. This definition comes from ITE/AV product (IEC/EN/UL 62368-1).

Class 2: When an electronic circuit is powered by class 2, its output current and power are under the limitation shown in UL 1310 Table 30.1, and the risk of fire can be reduced significantly. So, the safety distances and flammability rating of components can be much lower. Therefore, the plastic enclosure of these power supplies could use HB flammability rating to reduce cost. This definition comes from UL class 2 power unit (UL 1310).

 

Q23

Is it possible to build your own charging curve on the smart chargers when the pre-defined charging curves do not satisfy battery charging requirements?(Video tutorial Inside)

Ans

Yes, charging curves of smart chargers including ENC series, RPB series and RCB series can be set and adjusted through SBP-001, the charging programmer.
SBP-001 utilizes the software with the connection between the charger and itself to allow users to programme charging curves.
Adjustable functions are:
Charging parameter adjustment: Values of constant current (CC), constant voltage (CV), float voltage (FV) and tapper current (TC) can be set and adjusted.
Battery temperature compensation: Various charging voltage compensation is provided for battery at different temperature conditions.
Timeout setting: Fully programmable timeout during stages enables to be set to shutdown the charger to prevent battery over-charge.
Please refer to the user’s manual as link below for detailed information:
https://www.meanwell.com/webapp/product/search.aspx?prod=SBP-001
Following video is an example of demonstrating the ENC-120.
 

Q24

Why did the power supply shuts down during operation and after turning it off, I can restart the power supply again?

Ans

In general there are two circumstances that will cause the power supply to shut down. The first one is the activation of the over-load-protection (OLP). To deal with this situation, we suggest increasing the rating of the output power or modifying the OLP point. The second one is the activation of over-temperature protection (OTP) when the internal temperature reaches the pre-set value. All of these conditions will let the S.P.S. enter protection mode and shut down. After these conditions are removed, the S.P.S. will be back to normal.

Q25

What is the control mechanism for cooling fans?

Ans

Cooling fans have a relatively shorter lifetime (typical MTTF, Mean Time To Failure, of around 5000-100000 hours) compared with other components of power supply. As a result, changing operating method of the fans can extend the operation hours. The most common control schemes are shown as below:

  1. Temperature control: if the internal temperature of a power supply, detected by a temperature sensor, is over the threshold, the fan will start working at full speed, whereas, if the internal temperature is less than the set threshold, the fan will stop working or run at half speed. In addition, cooling fans in some power supplies are controlled by a non-linear control method whereby fan speed can be changed with different internal temperatures synchronously.
  2. Load control: if the loading of a power supply is over the threshold, the fan will start working at full speed, whereas, if the loading is less than the set threshold, the fan will stop working or run at half speed.

Q26

What are the common safety standards in America and Europe If power supply is used in battery charger?

Ans

The common safety standards is UL 62368-1, UL 1012 and UL 1310. UL 1012 and UL 1310 belong to the local national standards of the United States and Canada and are not applicable to other countries. The European market is dominated by EN 61558-1 and EN 61558-2-16.

Q27

What solution and products does MEAN WELL provide for industrial automation?

Ans

For industrial automation, MEAN WELL suggests using PMBus and CAN bus for digital control and monitoring. Please refer to the tech note link below for introduction and difference between the buses.
http://configurable.meanwell.com.tw/newsInfo.aspx?c=5&i=634
 

Model / interface PMBus CAN bus
 RSP-1600/DPU-3200
 UPH-1500/2500
By request By request
 RCP/RxB-1600
 DRP-3200/DxB-3200
 PHP-3500
 HEP-1000
As standard By request
 RCP-2000 As standard X

Q28

What should we pay attention to if system implemented magnetic component?

Ans

Nowadays, customer implement magnetic component in their system to achieve fast installation and maintenance. The magnetic component should keep as far as possible from PSU to avoid interference in the control circuitry of PSU. If limitation of distance is unavoidable, install a well magnetic-conducted metal plate (ex: steel plate, copper plate) between PSU and magnetic component to minimize the interference.

Q29

Cost of RMA service

Ans

Free repair service is guaranteed for product within warranty. For, products out of warranty, please check with service centers for a quotation.

Q30

CMU2 power management system solutions?

Ans

MEAN WELLs Intelligent power supplies equip with communication functions, such as PMBus or CAN bus, which can be controlled and monitored remotely and flexible for more applications. However, some may find its hard to get started. To reduce the time for the whole construction process in power management, MEAN WELL introduced the CMU2 power management system solutions. CMU2 is not only a fully digitalized master controller but also a Graphic User Interface device that can easily execute monitoring and controlling over intelligent power supplies. Moreover, it can optimize and increase system reliability of your power management system.
 
Application example:
National Synchrotron Radiation Research Center of Taiwan utilizes a power system built consist of many DRP-3200 to drive solid-state radio frequency power amplifiers, which generates high-frequency energy for boosting electrons to travel at nearly light speed. To match RF power required by the storage ring and best power efficiency, the output voltage of the power system must be adjustable between 42Vdc to 54Vdc modulation range for each operating point with a specific RF power level to achieve the best result. The CMU2 supports CAN bus protocol and is able to control output voltage of up to 48 supplies in a system simultaneously and precisely, which becomes the best solution for the application.

Q31

Response time of RMA service or inquiry?

Ans

General question will be replied within 48 hours. RMA service will be finished within 5 working days (excluding delivery time).

Q32

System power solutions?

Ans

Power requirement, output voltage levels and functionality vary from different projects and applications. To fulfill such requirements, MEAN WELL proposed a set of flexible and direct solutions called the system power solutions. The system power solution can be assembled and adjusted according to customer application requirement. The power is from 3200W to 128KW, the voltage range is 23.5V - 58.8V. In addition, customers also can choose different cabinet form factors. For more detailed information, please contact our local distributors.
 
Application example:
Maximum power of MEAN WELLs system power is up to 128kW, which makes it suitable for laser applications, including CO2 laser, fiber laser and diode laser.

Q33

What is the difference between linear and logarithmic dimming curves in DALI?

Ans

The brightness increasing in a steady/linear rate isn't observed as a linear increase to the human eyes. It is light source whose dimming curve is in logarithmic mode shows a linear increase to the human eye. There are linear and logarithmic dimming curves selectable for users in DALI.

Q34

The status for WEEE and MEAN WELL's approach?

Ans

One of the most important changes to the new WEEE Directive 2012/19/EU was the changeover to open scope on 15 August 2018. 2018 therefore represents a turning point: since then, significantly more devices have been subject to compulsory registration than under the old Directive 2002/96/EC. For example, since 15 August 2018, the obligation has also applied to furniture and clothing or textiles with electrical functions. 

device categories (Recovery) (Reuse and Recycle)
  • Heat vectors
  • Devices that have an outer dimension of more than 50 cm (lare equipment)
85 % 80 %
  • Screens, Monitors and devices, that have a surface larger than 100 cm2
80 % 70 %
  • Devices that have an outer dimension of less than 50 cm (small equipment) Small devices for the information and telecommunication technology, where the outer dimensions are less than 50 cm.
75 % 55 %
  • Lamps
-
81 %
 
According to the WEEE regulations, in addition to providing 3R dismantling reports of products, each member country must also establish a complete recycling system for producers to register, and report the statistical results of the Executive Committee on time.
 
The above products generally refer to END system products. MEAN WELL will continue to provide the 3R dismantling report for the Adaptors and external Battery Chargers for the system vendor to perform the final recovery rate evaluation.

Q35

What is "Inrush Current"? What will we notice?

Ans

At input side, there will be (1/2 ~1 cycle, ex. 1/120 ~ 1/60 seconds for 60 Hz AC source) large pulse current (20~100A based on the design of S.P.S.) at the moment of power on and then back to normal rating. This "Inrush Current" will appear every time you turn on the power. Although it will not damage the power supply, we suggest not turning the power supply ON/OFF very quickly within a short time. Besides, if there are several power supplies turning on at the same time, the dispatching system of AC source may shut off and go into protection mode because of the huge inrush current. It is suggested that these power supplies start up one by one or use the remote control function of S.P.S. to turn them on/off.

Q36

How to choose a suitable power supply for a charging application?

Ans

MEAN WELL has launched ENC, HEP-600C, GC, PA, PB, RPB and RCB series for battery charge applications (30~360W). However, if these models still cannot fulfill customer’s requirements, there is an alternative for the purpose. Power supplies with constant current limiting as overload protection are suggested. Charge current varies in battery percentage (full or flat), there is high possibility to trigger overload protection when battery is low, those with overload protection as hiccup or shutdown will stop charging the battery in low battery condition. Yet, using a power supply as charging purpose is considered as over load usage, modification is required. Please contact MEAN WELL for the request.

Q37

What is PFC?

Ans

Power Factor Correction or PFC is to improve the ratio of apparent power to real power. The power factor is around 0.4~0.6 in non-PFC models. In models with PFC circuit, the power factor can reach above 0.95. The calculation formulas are as follows: Apparent Power=Input Voltage x Input Current (VA), Real Power= Input Voltage x Input Current x Power Factor (W).
From the point of view of environment friendly, the power plant needs to generate a power which is higher than apparent power in order to steadily provide electricity. The real usage of electricity is defined by real power. Assuming the power factor is 0.5, the power plant needs to produce more than 2WVA to satisfy 1W real power usage. On the contrary, if the power factor is 0.95, the power plant only needs to generate more than 1.06VA to provide 1W real power, It will be more effective in energy saving with PFC function.
Active PFC topologies can be divided into single-stage active PFC and two-stage active PFC, the difference is show as in the table below.

PFC topology Advantage Disadvantage Limitation
 Single-stage
 active PFC
 Low cost
 Simple schematic
 High efficiency in 
 small 
 watt application
 Huge Ripple
 complex feedback 
 control
 1.Zero “hold up time”. The output is
    affected by the AC input directly.
 2.Huge ripple current results in lower LED life
    cycle.(drive the LED directly)
 3.Low dynamic responds, easily affected by
    load.
 Two-stage active
 PFC
 High efficiency
 Higher PF
 Easy feedback control
 High adoptive against 
 load condition
 Higher cost
 Complex schematic
 Suitable for all kinds use

 

Q38

What is LVLE ? If the power supplies can meet LVLE, what is the benefit for the end product?

Ans

According from UL8750 definition below:
a. 0-30Vdc output voltage: Maximum 8 amps
b. 30-60Vdc output voltage: 150/V amps
If the power supplies can meet LVLE , the end product does not need the fire enclosure.
 

Q39

What is the maximum communication distance for Mean Well products equipped with CAN bus communication interface?

Ans

MEAN WELL's CAN bus products meet ISO 11898 and the bus rate is 250kbps. Max. communication distance is at least 150m for the products.

Q40

What are the applications with serial connection?

Ans

There are two different applications when PSU are connected in series. One is to generate plus minus voltage, another is to increase total output voltage. Connection methods are as follows:
(1) Connection for plus and minus voltage are shown as follow

(2) To increase the total output voltage (Output current remain the same). Diode connect in parallel at output
      side of the driver is necessary to prevent damage during start up. The voltage rating of diode shall greater
      than V1 + V2( shown as figure below), in addition, peak forward surge current rating shall greater than
      rated current.

* Because part of the signal ground is shorted with output ground, strongly suggest to use isolated signals to
   achieve control scheme, in order to prevent damage to the product.
 

Q41

How to recognize an authentic MEAN WELL product?

Ans

The best way is to purchase MEAN WELL product from an authorized distributor listed on official website. Customer can enter serial number into the “Product Warranty Period Check” system and verify if the serial number matches MEAN WELL record or not. When in doubts, please check with MEAN WELL local representatives or offices.

Q42

IOT wireless IOT wireless lighting control solutions?

Ans

Some of our customers demand a solution that can switch the lights on/off and dim the lights wirelessly by a smart phone or tablet. To satisfy such requirements, MEAN WELL released Bluetooth low energy wireless lighting control solutions. MEAN WELL cooperates with leading technology companies of Casambi, Tuya and Silvair and launched two series of IOT wireless LED drivers, LCM-25/40/60-IOT and PWM-60/120-200-IOT. LCM-IOT series is a constant current mode driver and suitable to directly drive LED lamps; as a constant voltage mode driver, PWM-IOT series is suitable for LED stripes.
 
Application example:
LCM-25IOT operates with LED lamps for indoor lighting.

 

Q43

DALI smart lighting control solutions?

Ans

DALI (Digital Addressable Lighting Interface) is used to provide control over, and communication between, the drivers in a lighting system. DALI also enables lighting control to set up easily and reduce installation cost. As the DALI Association keeps adding new lighting control functions, MEAN WELL not only has DALI 1.0 version digital lighting control products, but also is dedicated to launch new products with the lasted regulation of DALI 2.0. Compared with DALI 1.0, DALI 2.0 adds definitions and functions of the input device and control device, improving and completing the overall DALI lighting system. In the future, LED driver will become a basic lighting device of DALI 2.0 control system.
 
Application example:
20 sets of LED panel lights with LCM-40DA are installed in an office. There are 3 different areas organized in the office, the designer can assign these 20 lights into 3 different groups through the DALI controller. It is easy to set up and easy to change in the future.

MEAN WELLs DALI 1.0 products:
LCM-25DA/40DA/60DA
LCM-40UDA/60UDA
ELG-75CDA/100CDA/150CDA/200CDA/240CDA
ELG-75DA/100DA/150DA/200DA/240DA
HLG-320-CDA
HBG-100DA/160DA/200DA/240DA
HBC-100PDA/160PDA
HVGC-480ADA/650DA
ODLC-45DA/65DA
LDC-35DA/55DA/80DA
PWM-60DA/90DA/120DA
IDLC-45DA/65DA
IDPC-45DA/65DA
DAP-04
LDD-H-DA

MEAN WELLs DALI 2.0 products:
LCM-25DA2/40DA2/60DA2
PWM-60DA2/90DA2/120DA2/200DA2
ELGC-300-L/M/H-ADA
HBGC-300-L/M/H-ADA
HVGC-1000-L/M/H-DA
LDC-55DA2
DLC-02

Q44

How to check warranty years of a product model?

Ans

Warranty lengths are defined in specifications. Please check official website specification for more details.

Q45

What is main difference between DALI-1 and DALI2? Is there any precaution before use?

Ans

DALI-2 is an upgraded version of DALI-1. DALI-2 has been adjusted and optimized for the following contents.
1. More precise specification of electrical tolerances and restructuring of specification make DALI-2 less risk for
    malfunctions and increased data accuracy.
2. DALI-2 added 14 new commands/features and removed 1 command. The most important one is extended
    fade time, the range is from 0.1 second to 16 minutes.
3. DALI-2 optimizes its communication sequence between application controller, input device and control gear,
    allowing devices from different manufacturers to work together on the same DALI bus.
4. DALI-2 products must be fully certified by the DiiA Association before they are allowed to use the DALI-2
    trademark.
    DALI-1 and DALI-2 products can be used together. Compatibility issue is shown in the table below.

Configuration Description
DALI-2 application controller with
DALI-1 control gears
Compatible, but no DALI-2 new features in DALI-1 control gears
DALI-2 control gears installed into DALI-1 system DALI-2 control gears are compatible with the system

Q46

What is MOOP and MOPP?

Ans

a. MOOP: provide adequate protection to the operator
b. MOPP: provide adequate protection to the patient
c. MOP: only one protection
MW products declare 2xMOPP means that MW product can provide two adequate protections to the patient.
It minimum the risk and also suitable for the patient.

Q47

What is the difference between -V and COM which are marked on the output side?

Ans

COM (COMMON) means common ground. Please see below:
Single output: Positive pole (+V), Negative pole (-V)
Multiple output (Common ground): Positive pole (+V1, +V2,.), Negative pole (COM)

Q48

What are the requirements of parallel connections? What are the differences between parallel and redundant.

Ans

When power supplies are connected in parallel, mostly, is intent to increase the output current. Due to the design of active current sharing, they are mostly without reverse current protection, therefore, they are not the best solution when talking about redundancy. For redundant purpose, please choose the PSU with redundant function or implement external redundant modules. Be sure that the difference in output voltage and wiring impedance, should be as small as possible.
1. Use PSP models as example, connect P(LP/CS) terminals together (Please refer to the parallel function of
    specification). Input and output should be connected in parallel before connecting to the AC source and
    loads. Shown as in picture below (some S.P.S. require a minimum load after paralleling).

2. Output voltage difference between S.P.S. units should be as small as possible, normally < 0.2V.
3. The power supplies should be paralleled with short and large diameter wiring together first, and then
    connected to the load.
4. After paralleling, the maximum usage of total power should be around 90% of the rated total power.
5. When power supplies are paralleled, if the load is lower than 10% of rated load of individual S.P.S. The LED
    indicator or signals (Power Good、Pok、Alarm Signal) may malfunction.
6. To ensure that the load current is effectively shared in parallel operation, in general, it is recommended not to
    use more than 4-6 power supplies at one time.
7. In some models, the +S, -S terminals should be used to reduce unstable pulsation of output voltage.

Q49

Why I can not turn on the power supply smoothly when the loads are motors, light bulbs or capacitive loads?

Ans

If you connect the S.P.S. to motors, light bulbs, or high capacitive loads, you will have a high output surge current when you turn on the S.P.S. and this high surge current will cause failure of start up. We suggest using S.P.S. with constant current limiting protection to deal with these loads.

Q50

In MEAN WELL's catalog, we see AC and DC at input, what is it all about?

Ans

Due to different circuit designs, MEAN WELL power supply's input consists of three types as below:
(VAC≒VDC)
a.85~264VAC;120~370VDC
b.176~264VAC;250~370VDC
c.85~132VAC/176~264VAC by Switch; 250~370VDC

  • In a and b inputs models, power supply can work properly no matter under AC or DC input. Some models need correct connection of input poles, positive pole connects to AC/L; negative pole connects to AC/N. Others may require opposite connection, positive pole to AC/N; negative pole to AC/L. If customers make a wrong connection, the power supply will not be broken. You can just reverse the input poles and power supply will still work.
  • In c input models, please make sure that you switch the 115/230V input correctly. If the switch is on the 115V side and the real input is 230V, the power supply will be damaged.           

Q51

What is the difference between EN 61558-1/EN 61558-2-16. EN 60335-1 and EN 62368-1?

Ans

The different requirements are as follow table, this table shall apply the altitude less than 2000m, Pollution Degree 2, OVC II and the rated voltage below 250Vac.

  EN 62368-1 EN 61558-1
EN 61558-2-16
EN 60335-1
DC-DC equipment is YES NO YES
Requirement the insulation between SELV and Protective earthing conductor NO YES (Basic insulation)
Limited for earth leakage current 7.07mApk 2mArms 0.75mApk
Requirement for capacitance discharge test 2 sec < Table 5 of IEC 62368-1 1sec < 60V 1sec < 34V
Requirement for bonding trace With terminal sizes that are not more than one size smaller than in Table 32 of IEC 62368-1; or with the limited short-circuit test of Annex R; 40A grounding test shall be performed 25A grounding test shall be performed and the shall not be less than two bonding traces used
Electric strength test for basin insulation 2500Vdc 2100Vac 1060Vac
Electric strength test for reinforced insulation 4000Vdc 4200Vac 3120Vac
Glow wire test No need The test shall be performed
Minimum distance through insulation for the insulation tape No require for the distance through insulation but two or more layers are used; shall be more than 0.15 mm for supplementary insulation
shall be more than 3.3 mm for reinforced insulation
Minimum distance through insulation for the insulation sheet shall be more than 0,4 mm for supplementary insulation or reinforced insulation shall be more than 0.5 mm for supplementary insulation and shall be more than 1.0 mm for reinforced insulation
Bridged Capacitance One or more bridged Capacitance used One or more bridged Capacitance used shall not be less than two bridged Capacitances used
Requirement for the triple wire Wire with an insulation meeting the requirements of Annex K for use in windings

Q52

What is the maximum communication cable length for DALI/KNX/CAN bus/PMBus?

Ans

Please refer to the table.

Interface Length (m) Cable
DALI 300 1.5 mm^2
 
KNX
KNX power-KNX device : 350
KNX device-KNX device : 700
From – End : 1000
 
KNX cable
CAN bus 150 Normal communication cable
PMBus 10 Normal communication cable

Q53

How to acquire manufacturer support for further questions?

Ans

Please contact with the service team in your region.

Q54

KNX building automation control solutions?

Ans

KNX is the world standard for residential and building control, offering many new products for visualization and building automation systems on the market.
MEAN WELL has been promoting KNX building automation control technology for a green and sustainable society and has continuously launched KNX related products that meet International Standards, such as KAA-8R universal switch actuator and KAA-4R4V dimming actuator, depending on the application they are suitable with MEAN WELL various power supplies and LED driver. Based on the KNX architecture, KNX system engineers can easily program through the ETS system as needed during planning or use. So far, MEAN WELL continues to improve product integrity to meet the needs of end customers and system operators.
 
Application example:
The Blinder system is a major part of the intelligent building control. To meet the application demand, MEAN WELL developed KNX bus power supply KNX-20E and KNX-40E to provide KNX equipment power, while KNX logic switch actuator has KNX-KAA-8R. KAA-8R can be applied with a light sensor and electrical blinder or curtains to control the blinder system.

MEAN WELLs KNX products:
LCM-25KN/40KN/60KN
PWM-60KN/120KN/200KN
KAA-8R(-10)
KAA-4R4V(-10)
KDA-64
KNX-20E-640/40E-1280D
DLC-02KN

Q55

If there are service requirements not within regular after-sales scope, how to acquire support?

Ans

Please contact global customer service window:
alroy@meanwell.com

Q56

Burn-in power recycling?

Ans

Any manufacturer that produces electronic products and equipment must undergo burn-in and aging tests in the production process. However, the burn-in process consumes a lot of electricity. To improve the problem of power consumption, MEAN WELL uses our self-developed energy recovery power supply combined with the power monitoring system (CMU2) to recycle the power consumed during the burn-in test, which can reduce energy consumption by more than 70%, up to 90%. 
Please click the link below for detail and case study.
https://expo.meanwell.com/aboutRange.aspx?i=44

Q57

Where can I have the communication protocol for the products I want?

Ans

For models equipped with PMBus, such as RCP-1600, you can refer to the communication interface chapter in the users manual. For those recognized as optional (non-standard), such as RCP-1600-48CAN, please apply for it through your local distributor.

Q58

What is Type HL?

Ans

The requirement of Type HL is from UL8750. It provide one option for evaluation of LED drivers that are intended for use in a Class I, Division 2 hazardous location luminaires.
It is simplify the procedure for the manufacture to apply the explosion-proof luminaires.

Q59

What is MTBF? Is it distinct from Life Cycle? What is DMTBF?

Ans

 MTBF (Mean Time Between Failure) and Life Cycle are both indicators of reliability. MTBF can be calculated by two different methodologies, which are “part count” and “stress analysis”. The regulations, MIL-HDBK-217F Notice 2 and TELCORDIA SR/TR-332(Bellcore) are commonly used to calculate MTBF. MIL-HDBK-217F is a United States military standard, and TELCORDIA SR/TR-332(Bellcore) is a commercial regulation. MEAN WELL utilize MIL-HDBK-217F(Stress Analysis) as the core of MTBF. The exact meaning of MTBF is, after continuously using the power supply for a certain amount of time, the average time that the probability of proper operation is down to 36.8%(e-1=0.368). Currently MEAN WELL is adopting MIL-HDBK-217F, forecasting the expected reliability through Stress Analysis (excluding fans); this MTBF means the probability of the product can continue the normal work after working continuously up to the calculated MTBF time is 36.8% (e-1=0.368). If the power supply is continuously used at double the MTBF time, the probability of proper operation becomes 13.5%(e-2=0.135). Life Cycle is found by using the temperature rise of electrolytic capacitors under maximum operating temperature to estimate the approximate life of the power supply. For example, RSP-750-12 MTBF=109.1K hours(25°C); electrolytic capacitor C110 Life Cycle=213K hours (Ta=50℃)
 
DMTBF(Demonstration Mean Time Between Failure) is a way of evaluate MTBF。Please refer to the following equation for MTBF calculation.


Where

MTBF:Mean Time Between Failure

X2:Can be found in chi-square distribution

N:Number of sampling

AF:Acceleration factor, which can be derived from acceleration factor equation.

Ae=0.6

K(Boltzmann Constant)=(eV/k)

T1:Rated temperature of specification. Note: Kelvin will be the unit use for calculation

T2:The temperature that is used in the meaning of acceleration, and the chosen temperature could not result in physical change in materials. Note: Kelvin will be the unit use for  calculation.  

Q60

The output ground (GND) and frame ground (FG) is the same point in my system, can MEAN WELL's power supplies be used in such system?

Ans

Yes. Since our products are designed based on isolation concept, it will be no problem that the output ground (GND) and frame ground (FG) is the same point in your system. But, EMI may be affect by this connection.

Q61

What is power good and power fail signals and how can use it?

Ans

Some power supplies provide a "Power Good" signal when they are turned on, and send out a " Power Fail" signal when they are turned off. This is usually used for monitoring and controlling purpose.
Power Good: after the output of a power supply reaches 90% rated voltage, an TTL signal (about 5V) will be sent out within the next 10-500ms.
Power Fail: before the output of a power supply is less than 90% rated voltage, the power-good signal will be turned off at least 1ms in advance.

Q62

Why my DALI drivers cannot be addressed by a DALI master?

Ans

There are several reasons in the table:

Possible Cause Suggested Solution
There is no AC connected to the driver Try again after power on
DALI communication line is off Try again after connecting to the bus
Driver or controller is damaged Contact the maker for repair

If the problem still cannot be solved, please contact your local distributor or MEAN WELL for assistance.
 

Q63

When using MEAN WELL products, voltage is found on the outer case, is it normal?

Ans

Due to the requirement of EMI, capacitors are connected to FG(Case) for filtering, leading voltage encounter on the case. This effect is clearly state in IEC62384-1 regulation, such as equipment for IT application, <2mA is necessary, and it can be solved by proper grounding connection.

Q64

If the concentration of Hexavalent chromium(Cr6+) exceed > 0.13ug/cm2(IEC-62327-7-1 2015), does it mean that it does not meets RoHs standard?

Ans

  1. according to IEC-62327-7-1 2015, if the test result of Hexavalent chromium (Cr6+) > 0.13ug/cm2, it only stands for the existing of Cr6+, but it doesn't mean it failed the RoHs requirement (<1000 ppm(mg/kg).
  2. By using ISO3613 is another easy way to evaluate the result. Multiply the thickness of coating and the density of coating (ug/cm2 -> ppm(mg/kg). Ex (Cr6+)2 ug/cm2, thickness of coating: 5um, density of coating :7.14 g • cm−3. The result is 2 ug/cm2 * 5um * 7.14 g • cm−3=71.4 ppm (mg/kg)
  3. If the result is still not clear, using regulation of 2011/65/EU、2015/863/EU for final evaluation.
Test item (Cr6+)
Test method IEC 62321-7-1:2015
Pre-process Boiling water extraction
Measuring
equipment
UV-Vis
unit ug/cm2
Judgement (1)Using n.d stand for < 0.10ug/cm2以n.d. Meaning no Cr6+ is measured.
(2)result from 0.10ug/cm2~0.13ug/cm2, Meaning the result of Cr6+ is unclear.
(3)if the result > 0.13ug/cm2, Meaning Cr6+ is presented.

Q65

There is communication problem in my PMBus/CAN bus devices, how can I solve it or improve it?

Ans

There are several reasons in the table.

Possible Cause Suggested Solution
Addressing error Try again after re-addressing
Data rate error Please set 100kHz for PMBus models and 250kbps for CAN bus models
The power is OFF Try again after power on
The communication line is off Try again after connecting to the bus
Noise interference Add isolation IC before you MCU or controller to reduce noise
 
If the problem still cannot be solved, please contact your local distributor or MEAN WELL for assistance.

Q66

For certain need, is it possible to reduce the noise of fan?

Ans

Noise is directly related to the fan which is build into the power supply. Lowering the airflow of the fan means reducing the heat dissipation ability. It will also influence the reliability of the products. Furthermore, minimum airflow of fans is defined by Safety Organization and a safety appendage will be needed if using a new fan. If fan noise is a critical concern, we suggest to select FANLESS products or contact MEAN WELL for other possibilities according to the conditions of use.

Q67

I have an TN-1500 inverter. Why the LED indication of AC IN is not lit after mains input has been applied?

Ans

According to the mains voltage of different countries, the output of TN-1500 inverter 110VAC version can be altered to 100/110/115/120VAC. In the same way, TN-1500 inverter 220VAC version can be changed to 200/220/230/240VAC as well. When the inverter is set in UPS mode and the mains voltage fluctuates over ?5% of the set AC output voltage, the inverter will shift its power source from the city power to battery to remain the accuracy of the AC output Voltage. Meanwhile, the AC IN indicator on the front panel of the inverter will be turned off.

Q68

What should be noticed when installing a power supply in vertical and horizontal directions?

Ans

Most small wattage and fanless power supplies are mainly installed in the horizontal position. If you have to install it vertically because of mechanical limitation, you should consider the output derating due to the heat concern. The temperature derating curve can be found on the spec sheet. Regarding the power supplies with built-in fan or the application has forced cooling system, vertical and horizontal installations have less difference. Ex. In SP-150 derating curve, the ambient temperature difference in application is 5 Celsius from vertical to horizontal. The output wattage in forced cooling can be 20% higher than air cooling convection.

Q69

What are the protection forms of overload/overcurrent?

Ans

When current drawn exceeds the rating of the PSU, the protection circuit will be triggered to protect the unit against overload/overcurrent. 
Protections of overload/overcurrent can be divided into several forms:
(1)FOLDBACK CURRENT LIMITING
Output current decreases about 20% of rated current, shown as curve (a) in the figure below. 
(2)CONSTANT CURRENT LIMITING
Output current remains at a constant level and within the specified range while the output voltage drops to a lower level, shown as curve (b) in the figure below. 
(3)OVER POWER LIMITING
Output power remains constant. As output load increases, output voltage decreases in proportion, shown as curve (c) in the figure below.  
(4)HICCUP CURRENT LIMITING
Output voltage and current keep pulsing ON and OFF repeatedly when protection is activated. The unit automatically recovers when faulty condition is removed.
(5)SHUT OFF
 Output voltage and current are cut off when output load reaches protection range. 
NOTE: Protection mode of some of the products combines with different types of the forms mentioned, such as constant current limiting + shut down.

Recover method:
(1)Auto Recovery: PSU recovers automatically after faulty condition is removed.
(2)Re-power on: PSU restarts by manual AC re-power on after faulty condition is removed.
Note:Please do not operate PSU in overcurrent or short-circuit condition for a long period of time to prevent a shorten lifespan or damaging the PSU.

Q70

What are the frequently asked questions for KNX products and where can I find them?

Ans

Mean well divided KNX problems into 3 aspects: ETS/Firmware, Application Aspect and KNX Data Secure. Please refer to the link below for detail.
https://building.meanwell.com/qa.aspx?c=9
 

Q71

What is Ripple & Noise? How to measure it?

Ans

It is the small unwanted residual periodic variation of the direct current (DC) output of a power supply which has been derived from an alternating current (AC) source. The wave form is shown as figure below.

There are two AC contents, also known as Ripple and Noise (R&N), on the DC output. The first one, coming from sine wave rectification, is at a low frequency which is 2 times of the input frequency; the second one is at high frequency which is from the switching frequency. For measuring high frequency noise, configurations of an oscilloscope with a bandwidth of 20MHz, a scope probe with shortest ground wire possible, and add 0.1uF and 47uF capacitors in parallel with test point for filtering out noise interference are requires to be made.
 

Q72

Can MEAN WELL charger use on lithium or other types of batteries?

Ans

All MEAN WELL chargers are preset for lead-acid batteries. For other products that can customize the charging curve (such as ENC / NPB series), customers can customize their charging curve depending on the charging and discharging characteristics of batteries. If you have other requirements, please contact MEAN WELL distributor.

Q73

How to increase communication reliability for CAN bus?

Ans

As differential signaling, adding termination resistors at the both far end of the bus can minimize signal reflection and then increase communication reliability for the interface. A suitable resistor is 120 ohms +/- 10 ohms with mini power rated of 220mw.

Q74

Why cannot the current to be adjusted to zero when using CANBus?

Ans

The parameters of current adjustment when using CANBus are actually for current limitation adjustment. You can recognize this function as the PC function what MEAN WELL implements for other industrial PSU.

Q75

What is Withstand Voltage?How to measure it?

Ans

Indicates Hi-Pot Test or Electric Strength Test. The input should be shorted together as well as the output before test. The test will proceed under particular loop, such as I/P-O/P, I/P-FG and O/P-FG with certain high voltage value for 1 minute. (The typical leakage current is 25mA when testing with AC)
 

  1.  Hi-Pot Test is a way to ensure if the isolation between primary to secondary is done properly, preventing damaging to S.P.S. when facing high voltage between input and output. The test voltage should be gradually increased from 0V to preset level and remains at preset level for 60 seconds with raise time greater than 1 second. In mass production, the test period could be reduced to 1 second. If the leakage current flowing through the isolation material increases rapidly when applying test voltage, it indicates ineffectiveness of isolation (dielectricbreakdown). Corona effect/discharge or transient electrical arc is not considered as failure.
  2. When AC test voltage is applied, Y capacitors are the main cause of leakage current. A 4.7nF capacitor can cause leakage current of 5mA. According to regulations of UL-554, the Y capacitors should be removed for Hi-Pot test, which is not practical for mass production. The only solution is to increase the leakage current setting, typically 25mA, of test instrument. Presently, the criteria of leakage current are not defined in safety regulations.
  3. According to regulations of IEC60950-1, DC test voltage can be substituted when there are bridging capacitors coupled between primary and econdary circuits, so as to solve the problem of leakage current.
 

Q76

Does the power supply capable to operates at high altitude condition.

Ans

The limitation for MEAN WELL power to operate under high altitude are as follow:
1. Operating temperature should decrease every 3.5℃/1000m for fan-less power supplies.
2. Operating temperature should decrease every 5℃/1000m for power supplies with fan.
*Should there be any concern about safety insulation, please contact our sales representatives
 

Q77

Can I use BIC-2200 as an ordinary stand-alone inverter like NTS/NTU/TS/TN series?

Ans

No. The BIC-2200 is designed with grid-tie compatible, meaning that the BIC-2200 will enter anti-islanding protection and not generate any AC energy when disconnect the bidirectional power supply from the mains. Therefore, the BIC-2200 could not be used as an ordinary stand-alone inverter.

Q78

How does MEAN WELL define switching time of 1ms(BIC-2200)?

Ans

The switching time is the time period which current flow from one direction to another, under 5% of Vo variation. Please refer to the figures below for definition and actual waveform.

Test Result:

MODE BIDIRECTION SWITCH TIME Result
AC to DC Direction 1ms    888   us
DC to AC Direction 1ms    681   us
    
   

Q79

Why I cannot use battery mode and C/D control function in BIC-2200?

Ans

Battery mode and C/D control function only can be activated via CANBus communication interface. If you do need these functions, please contact our distributor and order BIC-2200CAN.

Q80

What is the definition of IP (Ingress Protection) ratings? And what is MeanWell’s IP68 definition.

Ans

MEAN WELL has incorporated dust proofing and water proofing into majority of its LED power supply design. Mainly based on the international standard IEC60529, detailed descriptions can be found in the following table:
(Note: PSUs with IP64 rating or above are suitable for indoor or outdoor applications in sheltered locations)

*IP64-IP66 level and IP67 with potentiometer products are suitable for damp indoor or sheltered outdoor environment. For actual installation limitations, please refer to the corresponding IP level tests.
*All products cannot be continuously submerged in water.
*The definition of IP68 by MEAN WELL: Immerse a unit under test in 1 meter below the surface of the water, tested with a dynamic condition where 12 hour AC on; 12 hour AC off.
Test duration: 1 month.

Q81

How do you select suitable MW LED power supply?

Ans

  1. Select suitable wattage based on customers system requirements and application methods. Must also take excess power and driving method into consideration.
  • For selection key points when using MW power supply to “directly” drive LED lamp refer to LED configuration and installation notes.
  • For selection key points when using MW power supply in combination with LED driver IC to achieve high precision current control refer to LED configuration and installation notes.
  1. Based on LED power supplys operating environment select suitable IP level and mechanical type (metal enclosure, plastic enclosure, and open frame PCB) for that environment.
  2. Is PFC function required or not? Single stage PFC is only suitable for LED load. Dual stage PFC is suitable for general applications.
  3. If LED system is based on direct drive, units with adjustable voltage and current should be considered for flexibility in changing voltage/current levels. Dimming function may also come in handy when LED brightness control is preferred.
     * Comparison Chart
        http://www.meanwell.com.tw/Upload/PDF/meanwell_LED.pdf
     * For those who chose to use single stage PFC products. Refer to What is the difference between single stage
       and two stage power supply.

Q82

How to select a MCB with S.P.S.?

Ans

A: Steps

  1. Check for the circuit breaker information in specification or installation. If it is not shown, you can calculate it according to the following steps.
  2. Enter MEAN WELL Expo with following LINK.  https://expo.meanwell.com/cbs/index.html
  3. Fill in the values of inrush current , T50(Note 3) and Rated AC current that is defined in the specification accordingly.
  4. The result must be verified onsite.

B: Calculation demonstration
Taking HLG-600H as an example, the inrush current is 70A, the T50 is 1000us, and the AC current under 230VAC is 3.3A. The result will be shown after the finishing of parameter entering.

The first column is the model of the circuit breaker, the first code is the classification of the circuit breaker, and the second code is the rated current. For example, B10 means B type with 10A rated current.
The second column indicates the maximum number of HLG-600Hs that can be connected to one circuit breaker. For example, if B10 is selected, only one HLG-600H can be connected, and if D16 is selected, four HLG-600Hs can be connected.

The following is a description of the classification of circuit breakers according to the tripping current characteristic curve:
 
Classification Tripping Current Applicable places
A (2~3)*In For protection of very sensitive circuits such as semiconductors.
B (3~5)*In Suitable for computers, electronic equipment and residential circuit protection.
C (5~10)*In For control circuits of general device, protection of illuminating circuits with high inrush current and all other supplementary circuits.
D (10~20)*In Protection for high inrush loads like transformers, solenoid valves, etc.

To operate with MEAN WELL power supplies, a MCB with a tripping characteristic “C” or “D” is recommended.(In : Rated Current)
Note: 1. MCB data adopts with ABB’s product, relevant data is only for reference. Different set-up may result difference.
          2. Please contact MEAN WELL technicians for product without T50 information.
          3. T50 is the time width of 50% of the inrush current value.



C: Inrush Current Limiter
For details, please refer to the following technical article " Introduction and Selection: ICL-16 Series and Circuit Breakers "
https://www.meanwell.com/newsInfo.aspx?c=5&i=765

Q83

What is the difference between 3-phase 3-wire and 3-phase 4-wire systems and how to wire?

Ans

There are two basic three-phase configurations: wye (Y) and delta (Δ). The delta connection is to connect the power sources or loads of each phase in turn to form a triangular ring. Star connection is to connect one end of the power sources or loads of each phase at one point to form a neutral point. If a neutral wire is drawn from this neutral point, the whole structure becomes a three-phase four-wire system.


                                                    Connection of 3 3Φ4W & 3Φ3W

Comparison of 3Φ4W & 3Φ3W

Connection Recommended products Application features
3Φ4W RST-5000/10000/7K5/15K Single-phase input available
3Φ3W SHP-10K Simple connection with AC main

Q84

What are the most common LED driving methods? What are its advantages and disadvantages?

Ans

Q85

What to consider when selecting LED power supply?

Ans

  1. Lighting system designed to work in direct drive mode
    1. The combined LED forward voltage range (upper and lower) must fall within LED power supplys constant current voltage range. For example, the LED Vf spec is 3.4~3.6V, when 6 are connected in series the combined Vf will be 20.4~21.6V. In this case, a 24V unit must be selected with constant current region of 18~24V.Ø
    2. For models with active PFC and system PF requirement is >0.9, load usage must be higher than as specified in the PFC spec. Relationship between PF and output load can be found in figure 1. The typical requirement is 75% load or above. Double check the spec for the model you are using to confirm actual requirement.
    3. In areas with unstable AC voltage such as heavy industrial zone or generator supply utility, please select general usage LED series from table 1.
  2. Lighting system designed to work with driver IC
    1. The start up voltage of driver IC should be as close to the power supply rated voltage as possible.
    2. Driver IC needs stable voltage to function properly. So, it is highly recommended to use general usage series from table 1.
    3. For models with active PFC and system PF requirement is >0.9, load usage must be higher than as specified in the PFC spec. Relationship between PF and output load can be found in figure 1. The typical requirement is 75% load or above.
    4. Double check the spec for the model you are using to confirm actual requirement. When using driver IC, possible system EMI issue could arise. After completing lighting system design, EMI must be double checked.

 

Q86

Why is that LED lamp designed with LED driver IC may sometimes cause power supply startup failure? (Output voltage gets clamped by LEDs and cannot rise to rated level)

Ans

Depending on circuit design, there could be different operational problems. See below:

  1. Boost mode driver IC:
    The startup voltage of such driver IC is significant lower than the total LED forward voltage. For this reason, the IC will start up at very low voltage level usually about 1/2 of the power supply’s rated voltage and to meet rated power requirement, the startup current will reach 2 times the power supply’s rated current. When the power supply is unable to provide this current, the LED CC driver will not activate.
  2. Buck mode driver IC:
    If the selected power supply voltage is significantly higher than the LED forward voltage. For example, power supply provides 48V and the LED lamp only needs 24V and the power ratings are equivalent. When power supply voltage reached the LED conduction voltage, the power supply will immediately go into constant current mode. At this moment, the required power to start up the LED + driver is larger than what the power supply can provide causing malfunction of the driver circuit and the power supply to be clamped at LED forward voltage. For boost mode design, we recommend raising the startup voltage of the driver IC to be as close to the power supply voltage as possible or incorporate soft start function (see fig. 3). Wait until the power supply voltage is established before starting the driver. When selecting power supply for buck mode, the output voltage of the power supply should be as close to the LED total voltage as possible with excess power available (LED power/0.85).
 

DIM PIN is the startup pin for most PWM based driver. It can also be designated as EN (Enable). DIM (or Enable) is at 0V the internal connection to SW pin will be open. When the DIM voltage reaches 1.5V (Typ), the IC will Turn ON. To set the Vstart for the DRIVER IC: Vstart = (VDIM/RB) x (RA+RB). The general rule is to set the Vstart at 5~10% higher than the total LED forward voltage.

Q87

What are CV, CC, and CV+CC which are often mentioned in LED power supply specification?

Ans

Q88

For a particular LED lighting design, each LED strip consists of 12 LEDs connected in series (VF=3.5V), 4 strips in parallel, and each strip requires 0.7A of drive current. Based on the above conditions, how do you select a suitable power supply?

Ans

First of all, the LED power supply must be able to work in constant current mode. LED forward voltage of each strip = 3.5V X 12pcs = 42V LED lamp total current requirement = 0.7A X 4 strips in parallel = 2.8A LED power requirement = 42V X 2.8A = 117.6W LED power supply’s rated voltage/power should be greater than what is required but should be as close to the actual requirement as possible. Use 48V/150W as the basic criteria to pick LED power supply then make sure actual voltage/power usage meets constant current region and PF>0.9 specifications (117.6W/150W = 78.4% > 75%). CLG-150A-48V with output current set at 2.8A can be used in this design.
Note: Each LED production lot will fall within a VF rank (e.g.3.4~3.6V). This LED tolerance must be taken into consideration during design.

Q89

What is the concept of constant power design? What's the difference when comparing to constant current design?

Ans

The driving method of constant power LED driver is same as the principle of constant current mode drivers. Except that, the maximum power of a general constant current LED driver will only be fixed at a single output voltage and output current. The constant power LED driver adopts a wide range of output voltage and current Design. Wide range of fixed maximum output power range, provide flexible and efficient LED voltage and current configuration, optimized size and inventory. As shown in the figure, the output voltage and current in between 232V/2800mA and 185.6V/3500mA can produce maximum output power of 650W.


 

Q90

Same LED configuration as in question B1 with the exception of additional driver ICs. What is a suitable power supply unit to use?

Ans

First calculate for required voltage by combining total LED forward voltage and driver voltage drop of 2V. LED forward voltage of each strip = 3.5V x 12pcs = 42V Driver circuit required voltage = 42V + 2V = 44V LED total current requirement = 0.7A X 4 strips in parallel = 2.8A Driver circuit required wattage = 44V X 2.8A = 123.2W LED power supply's rated voltage/power should be greater than what is required but should be as close to the actual requirement as possible. Use 48V/150W as the basic criteria to pick LED power supply then make sure actual voltage/power usage meets constant current region and PF>0.9 specifications (123.2W /150W = 82.13% >75%) CLG-150A-48 with output voltage set at 44V can be used in this design

Q91

Does MW LED power supply allow adjustment of output voltage and current levels?

Ans

LED power supply comparison table to see which MW LED power supply allows for V/I adjustments. A suitable unit can be picked based on the type of adjustment required. For the allowed adjustment range, please refer to the spec sheet. Tuning of the voltage and current levels can be done through the built-in VRs/potentiometers. PLN/ELN requires removal of the top cover in order to access the internal SVR1 and SVR2, see figure 9 for VR locations. For other series, the VRs can be accessed through IoADJ and VoADJ holes after rubber stopper removal. After adjustments have been made, please make sure rate power is not exceeded and the rubber stoppers are properly reassembled.

Q92

Can LED power supplies be connected in parallel?

Ans

MW LED power supply does not have parallel “current sharing” function so it is not suitable for parallel connection. For high power requirement, please select higher wattage power supply or divide LED load into smaller subsections to be powered by individual power supplies. Example of such LED configuration can be found in figure 5. As shown in fig. 5, the connection between -V of the LPC-35 units should be severed and not connected in common. On the contrary, small wattage LED loads can be connected in parallel and be powered by a single high wattage power supply. But, the ability to divide current evenly must be taken into consideration.

Q93

How high can MEAN WELL LED products withstand under surge test.

Ans

In the MEAN WELL LED power supply product line, the XLG optional products have the highest lightning surge withstand capability, which can reach 10KV/line 6KV/line-to-ground. If higher SURGE capability is needed, adopt ZNR (470V) or gas tube (500V) externally as alternate solution. More to that, the overall safety requirements need to be reconsidered. When multiple lamps are used, a lightning protection device (SPD: Surge protection device) can be installed to meet the requirements of regulations.



Q94

Can MEAN WELL IP67 products exposed to open field?

Ans

Please check if the IP67 is equipped with ADJ function or not. Due to the mechanism design of potentiometer for IP67 products, the protections are not as perfect as BLANK type. Therefore, please choose BLNK version when application is not sheltered.

Q95

To design a LED street lamp, what solution can MEAN WELL offer?

Ans

Q96

Can MW recommend the dimmers compatible to the 3 in 1 dimming circuit?

Ans

3 in 1 dimming is the most commonly applications used in LED dimming with the feature that it does not have to work with any specific dimmer. The only thing that has to be verified is that whether the dimmer (1~10V/10V PWM/resistance) is compatible with the definition advised in our specs.

Q97

What are the right product to use when intent to dimmed strip lights?

Ans

Most strip lights contain a resistor in series, as the result, constant voltage LED driver must be used in this kind of application. We recommend to choose dimmable constant voltage LED drivers such as, PWM/IDLV/ODLV.

Q98

What is the main difference between 1~10V dimming and 0~10V dimming regarding applications?

Ans

With 1~10V dimming, the lighting unit can be dimmed down to 10%; with 0~10V dimming, it can be dim down to 0%, or say, dim to “off”.

Q99

What is the current accuracy of LED SPS?

Ans

For LED SPS output current accuracy, please refer to product specification. For CC model, “CURRENT ACCURACY” is listed in SPECIFICATION section. For CC+CV model, please reference the OVER CURRENT range in PROTECTION of the SPECIFICATION section.

Q100

How can we learn how many units of the model with 3 in 1 dimming can be controlled by one dimming device?

Ans

3 in 1 dimming circuit would drain 0.1mA per model. Dividing the rated current of the dimmer by the 0.1mA, and we could know how many units can be controlled by one dimming device. For resistance dimming applications, resistance for 100% dimming output would be 100K ohm divided number of models.

Q101

Can we use LED CC model as a charger?

Ans

MW has several charger products, and we suggest choosing them first. Chargers would be more suitable since they are designed for charging applications. Safety & Approvals should be taken into account. If you really cannot find a proper model in our chargers series, our LED CC models can be used as charger. Please choose suitable products after confirming the current and voltage specification on the datasheet of the battery.

Q102

What is the difference between Single Stage and Two Stage Power Supply?

Ans

There are 2 types of Power Factor Correction circuits; one is Single Stage and the other is Two Stage. Single stage power supply combines functions of power factor correction and converter in one circuit but two stage use two separate circuits. Compared to Single Stage, Two Stage design is more complex and costly but the immunity performance of Two Stage PSU against AC mains is much better than that of Single Stage PSU; in addition, Two Stage manifests better ripple noises performance on output. Owing to that Single Stage is only suitable for fields with quality AC mains but Two Stage can be used in serious circumstance for LED drivers or as industrial switching power supplies.

Q103

How am I supposed to read the LED V-I dotted line & tolerance definition in the specification?

Ans

Mean Well’s LED product specification normally exhibits V-I characteristics. Per the characteristics, there are generally two types of drivers, “CC” type and “CC+CV” type. “CC” type of driver is suitable only for LED applications whereas “CC+CV” for either LED applications or general switching power supply applications. The section that is not suitable for LED applications are represented by dotted line, and based on the protection procedures it can be categorized into hiccup mode and constant current mode; in this section, the tolerance of current is not defined but only the characteristic of current is displayed. If customers attempt not to see a very high current under short circuit condition, those models with hiccup mode for this section can be selected; if there are applications with motors or capacitive load, those with constant current can be chosen.

Q104

There are so many MW dimming products. How can I make a choice? What are the pros and cons?

Ans

First, you have to know your Led lamp specification in order to screen out a suitable Led driver range (Wattage, Voltage, Max Current CC or CV). From those ranges, further check a compatible dimming function. Hereunder is a table to show you the pros and cons of Dimming Function you can find in MW's catalogue.

Q105

Can I use MW LED drivers at full load continuously? Most of the AC/DC power supply are suggested to use at 70% load.

Ans

LED Drivers are recommended operate at full load as long as it observes the working temperature specified in the datasheet, which means Tc measurement results should be equal to or less than the stated Tc in the datasheet. 5 years warranty complies as long as drivers operate within working Temp and Tc. Limit as well.

Q106

When the MTBF of MEAN WELL product is shorter than competitor’s, does it mean that the quality of MEAN WELL is lower than other brands?

Ans

The answer is NO. The calculation of MTBF contain many variations, the version of MTBF, stress of component and the number of components can make difference. Not like other OEM/ODM companies, MEAN WELL sells standard power supply with our own brand, so the MTBF parameter is not able to customized one by one according to the application. Therefore, MEAN WELL still seek for improvement and MEAN WELL re-examined the MTBF parameters of TELCORDIA SR/TR-332(Bellcore) and implemented an optimization. MEAN WELL reviewing the supplier quality policy and accompanying with IQC/OQC/FQC…etc., all the ways to after-sales service, ensure preventing recurrence, which not only brings the quality of MEAN WELL products to another level, but it also changes the status of the quality factor πQ of the MTBF equation as shown in Table 1 according to TELCORDIA SR/TR-332(Bellcore) regulation. Leading the MTBF reading can be optimized from Level 0~I to Level I~II. For more detail, please refer to https://www.meanwell.com/newsInfo.aspx?c=5&i=1026.
Although MTBF can be one of the parameter that represent quality, but it’s not the only parameter what we should consider when choosing a power supply. From Brand, price, lead time, service to warranty, all of them shall be well considered together.

Table 1. Device Quality Level Description and Factor of TELCORDIA SR/TR-332(Bellcore)

Q107

Can I wire LDD or LDH in parallel or series?

Ans

LDD/LDH series comprises switching components; series or parallel connection will damage these switching components.

Q108

How to find products you need in MEAN WELL website?

Ans

Click “Products” on the website Menu. Four methods are provided to search MEAN WELL power supply products.
1. Series Search
    Click “product style” such as DIN Rail, LED Driver or Charger, and you can rapidly find the corresponding
    product series. Through wattage and function information, you will find the products you need.
2. Quick Search
    By choosing product type and electrical characteristic, related power supply and specification are shown
    below.
3. Direct Search
    If you know the series name, click “magnifier” icon from the upper right of MEAN WELL website, and type
    the complete or part name to search the related product information.

Q109

What product information does MEAN WELL website provide?

Ans

The product information shown on MEAN WELL website is as below.
1. Specification
    Details of product features, electrical specification, function, and mechanical specification can be found in the specification page.
2. Test report
    The report content includes design verify test, safety & EMC test, and reliability test, ensuring the user safe through inspection,
3. Certificate
    The certificate from accredited certification body is provided for customers' reference.
4. User manual
    User manual provides detailed product instruction and considerations.

Q110

If the suitable product cannot be found, how to contact MEAN WELL?

Ans

You can send your product demand to local distributors at first, and the distributors can provide immediate service and suggestion. Besides, you can find “Contact Us” on website to fill out Sales Inquiry Form and we will reply your query promptly.

Q111

How to know the product discontinued information?

Ans

Providing the best price-performance ratio of standard power supplies and services are MEAN WELL enterprise mission. To comply with the latest updated international safety regulations, MEAN WELL develops the corresponding new high cost-performance products. Through “Products”, you can see “Not Recommended for New Design” and “Discontinued Products”. The former one shows models which will be gradually discontinued and replaced in the future. The latter one is models that are going to be discontinued and EOL.

Q112

What is the purchasing channel for MEAN WELL products?

Ans

For small and medium quantity demands, local distributors offer better price and enough stock for your timely delivery. However, for further contact to MEAN WELL, please fill out “Sales Inquire Form” in the “Contact Us” page, service will be offered promptly.

Q113

How to know MEAN WELL distributors information?

Ans

MEAN WELL has authorized distributors all over the world. You can find “Distributors” to search local distributors by area and product type. Our distributors will surely provide high quality service.

Q114

How to learn MEAN WELL new product launching announcement?

Ans

MEAN WELL develops new products constantly. Click “New Products” in “News” page for acquiring complete model information and key features.

Q115

Where to find the product test report?

Ans

To discover product complete test reports, click product information link and the report shows various information, such as electrical characteristic, protection, control function, stability, safety, and EMC.
 

Q116

How long can I extend DC cable of the driver?

Ans

Owing to line (voltage)-drop, we suggest the extension made from AC cable. In case DC cable extension is necessary, please consider Line-Drop leading to insufficient Vf so that the LED model or lamp may fail to switch ON. Moreover, EMC performance and characteristic may also be affected by DC cable extension.

Q117

Why is that during LED power supply operation the LED sometimes varies in brightness or flickers?

Ans

MW developed many power supplies series specifically for LED application. Single stage PFC was used in such developments due to low cost. This topology has the following restrictions:

  1. AC fluctuation
    This topology does not use input bulk capacitor. For this reason, in areas with low AC quality, output voltage and current may become unstable causing variation in LED brightness. If the input AC voltage is stable then this problem will not occur.
  2. Output ripple
    This is also caused by lack of input bulk capacitor. As compared to power supplies using dual stage PFC, the ripple will be significantly larger (see Figure 4). There could be instances where the low end of the ripple may be too low for the driver IC to operate properly and the LEDs will start to flicker. To solve this type of problem, the output voltage can be adjusted higher so the low end is higher than the driver’s minimum working voltage. Or simply select a PSU with higher rated voltage.
  3. Current harmouics
    Single stage PFC power supplies are optimize for constant current drive. Using these supplies as constant voltage sources (such as application including cascading a constant current driver IC), the harmonics might be worsen in this case. When operating in areas with unstable utility voltage or with driver IC, we highly recommend using general application types as found in table 1. Avoid using single stage PFC if possible, or contact MEANWELL.

Q118

What's the reason that dimming is not working with MEAN WELL dimmable LED driver.

Ans

First of all. Determine the driving method of LED lamp. If the lamp is driven by constant current, forward current shall be within specification. On the contract, if it's driven by constant voltage, then user must check if they are using the right product to dim the LED lamp, such as PWM series or model with PWM output in XLN-60/XLC-60 series.