2024 MEAN Well Safety Certification version status



What is a 3+N system solution?


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.


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


  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.


Points on connecting wires used in power supplies?


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.


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?


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.


Notes on choosing a switching power supply?


  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.


What are the intelligent products of MEAN WELL?


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:
>>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:

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:
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:
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:
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:


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


For Building automation, MEAN WELL utilizes KNX as the solution. Please refer to the KNX building automation website for detailed information and relevant applications.


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


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.


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


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.


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


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.


How to apply a RMA service?


  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.


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


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.


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


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.


Notice on sending an RMA back


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.


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


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.


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


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.


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


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


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


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.


How many units can be controlled by CASAMBI app?


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


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


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).



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)


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:
Following video is an example of demonstrating the ENC-120.


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


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.


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


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


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


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:
Please contact our team member in your region for instant service.


Cost of RMA service


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


CMU2 power management system solutions?


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.