MEAN WELL’s power supplies have been used in a wide variety of electronic equipments, including  factory control, IT, communication, appliances, medical, lighting, billboards, security, vehicle, etc…. , which is capable of meeting your needs.
 

Application Aspect

Q1

What is different between information (EN60950-1/IEC62368-1) and medical (EN60601-1) safety standard?

Ans

According to safety standard, the leakage current in EN60950-1 Class I cannot exceed 3.5mA; in EN60601-1 cannot exceed 0.3mA. Others criteria like safe distance and numbers of fuse are also different. Please consult the diagram below:

Q2

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.

Q3

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.

Q4

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.

Q5

If you are using power supply with -V connected to AC FG and is failing leakage current test from +V to AC FG, what can you do?

Ans

If the system is in the early development stage, it is suggested to switch to a power supply with -V and AC FG isolated or directly use a Class II power supply. If the system is already in late design stages and the power supply can no longer be changed, then the grounding test must be conducted to ensure the proper connection to ground and note that the wire gauge needs to be thick enough (16AWG recommended). In addition, the system’s enclosure should have a grounding screw with a grounding cable, and the purpose shall be explained in the function manual.

Q6

If your system and power supply fail the RS test during EMS testing, what can you do?

Ans

Suggest customer add a ferrite core near the power supply side of the output cord, which can help suppress interferences. If the power supply is an adaptor, it is most effective to clamp the core within 25mm of the strain relief (SR).