A: In general the models and naming are as below, please refer to each models datasheet for details.            

 Series name  Output Voltage & Output type Option for Screw Terminal
 AOCH10 -5S-A2
AC-DC ITE, Household, Switching Power start with A 5=5WSingle = S

Dual = D
5D or 5S12S

Triple = *S*D
 A2 or A5
For instance: AOCH10, ARF500  
AC-DC Medical, Medical switiching start with M  
For instance: MQF, MTC, MFC  
DC-DC starts with S or Z  
For instance: SW, ST, ZB, ZC  

1.When using the power supply, the working temperature is defined as of it is measured from 1 cm next to power supply and shall be derated if working on a higher temperature environment. Please refer to the product datasheet for the derating curve of the temperature versus output power.

2.It is suggested to choose a power with a rating of 30% more power than the system actual needs, in order to increase the reliability of the power supply. For instance, if a system needs a 100W source, please consider 130W or higher. It can effectively improve the reliability of the power supply in the system. 

3.Choose function for your application

  • Protection function: Over Temperature Protection (OTP), Over Voltage Protection (OVP), Over Load Protection (OLP), etc.
  • Application function: Signaling Function (POWER GOOD, POWER FAIL), Remote Control, Remote Sensing, Parallel connect, etc.
  • Special function: Power Factor Correction (PFC). 

4.Make sure the selected model to be qualified with the required safety standards and EMC regulations.

A: In general ARCH power supply can be used in this frequency range, however, if the frequency is too low that may decrease the efficiency and the PF value. In addition, if the frequency raises up, the leakage current will increase.

A: The design and its application of each power supply is different, some of ARCH’s power supply will require minimum load, for the details please refer to the minimum load value in the datasheet.

A: In general it could be that 
1) overloading causing the Over Load Protection (OLP) to be activated, suggest to increase the rating of the output of the power or modify the OLP point. 
2) overtemperature causing the activation of the over temperature protection (OTP). Suggest to choose the power supply based on required ambient temperature and rating.

A: There will be a large pulse current (depending on the design, it is about 20~100A, refer to the product specification) at the moment when turning on the power. It will be normal rating after system is on. It may happen regularly at the moment when turning on, it is normal and will not damage the power supply. However, it is not recommended to switch on/off the power supply constantly. Please note, if need to switch on multiple power supplies, suggest to switch on one by one and not all at the same time.

A: MTBF and Life Cycle both are common indicators of product reliability. We follow the standard of MIL-HDBK-217F Notice 2 (Stress Analysis) as the calculation base for MTBF. MTBF (Mean Time Between Failure) is the expected value of reliability prediction, which refers to the average time when the reliability of the power supply drops to 36.8% after continuous operation for a period of time. 

Life Cycle refers to the result of the temperature rise test of the capacitors and electrolysis at maximum operating temperature, to calculate the reference life time of the capacitors, electrolysis and the power supply. 

A Due to the requirements of EMI, the input of the power supply may connect to the FG (case) through the Y capacitors. This may cause the case to be charged. That’s the reason for a clear definition of the leakage current value defined in IEC/UL/EN safety regulation. ARCH power supply is certified with these safety regulations, this will be solved when the power supply is connected to the ground properly.

A: Under different environment and application the EMC test result may be different, once the power supply is installed in customer’s application, ARCH couldn’t guarantee that the final system will meet the EMC requirement automatically. The test result we provided is based on the power supply stand alone.

According to the Safety standard, the leakage current in EN60950-1 Class I cannot exceed 3.5mA; in EN60601-1 the leakage current cannot exceed 300uA. The safe distance and numbers of fuse are also different when measuring.

Creepage distance/Clearance distanceBasic insulation≧2.5mm / 2mm4mm / 2.5mm
Workingvoltage:250Vrms(Max.)Supplementary insulation≧5mm / 4mm8mm / 5mm
  Electric strength test     Basic insulation≧1500Vac1500Vac
Supplementary insulation≧3000Vac4000Vac
Leakage current  Class Ⅰ≦Handheld type  0.75m A-
other 3.5m ALeakage current of ground300uA
Leakage current of case100uA
Class Ⅱ≦250μALeakage current of case100uA
Number of fuseClass ⅠLx1Lx1 , Nx1
Class ⅡLx1
Operating TemperatureBy manufacture defined≧ 40 ℃