FAQ

Question 1

Q1.Application Note

Accepted Answer

.button {
 background-color: #4CAF50; /* Green */
 border: none;
 color: white;
 padding: 10px 10px;
 text-align: center;
 text-decoration: none;
 display: inline-block;
 font-size: 16px;
 margin: 4px 2px;
 -webkit-transition-duration: 0.4s; /* Safari */
 transition-duration: 0.4s;
 cursor: pointer;
}

.button1 {
 background-color: white; 
 color: black; 
 border: 2px solid #4CAF50; /* Green */
}

.button1:hover {
 background-color: #4CAF50; /* BLUE */
 color: white;
}

.button2 {
 background-color: white; 
 color: black; 
 border: 2px solid #008CBA; /* BLUE */
}

.button2:hover {
 background-color: #008CBA; /* BLUE */
 color: white;
}

.button3 {
 background-color: white; 
 color: black; 
 border: 2px solid #f44336; /* RED */
}

.button3:hover {
 background-color: #f44336; /* RED */
 color: white;
}

.button4 {
 background-color: white;
 color: black;
 border: 2px solid #e7e7e7;
}

.button4:hover {background-color: #e7e7e7;}

.button5 {
 background-color: white;
 color: black;
 border: 2px solid #555555;
}

.button5:hover {
 background-color: #555555;
 color: white;
}

AC-DC Application Note
 AC-DC Application Note-AZC
 DC-DC Application Note
 ABR300 Application Note
 MQF500 Current Sharing Application Note

Question 2

Q2. How do I choose the models?

Accepted Answer

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
 
-
5
S
-
A2

AC-DC ITE, Household, Switching Power start with A
 
5=5W
Single = S5SDual = D5D or 5S12STriple = *S*D5S12D
 
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

Question 3

Q3.Notes on selecting a power supply?

Accepted Answer

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.

Question 4

Q4.Can ARCH power supply be using in the frequency range of 45~440Hz? If yes, what is the impact?

Accepted Answer

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.

Question 5

Q5.Will minimum load be required to ARCH power supply?

Accepted Answer

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.

Question 6

Q6.Why power supply shut down during operation?

Accepted Answer

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.

Question 7

Q7.What is Inrush current? What to pay attention to?

Accepted Answer

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.

Question 8

Q8.What is differential between MTBF & Life Cycle?

Accepted Answer

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.

Question 9

Q9.The case seems to be charged, is it normal?

Accepted Answer

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.

Question 10

Q10.Arch power supply has CE marking, when install in customer’s application, will it meet EMC requirement for sure?

Accepted Answer

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.

Question 11

Q11. Is any different between Information (EN60950-1) and Medical (EN60601-1) Safety standard?

Accepted Answer

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.

Subjects
IEC60950-1
IEC60601-1

Creepage distance/Clearance distance
Basic insulation≧
2.5mm / 2mm
4mm / 2.5mm

Workingvoltage:250Vrms(Max.)
Supplementary insulation≧
5mm / 4mm
8mm / 5mm

Electric strength test
     Basic insulation≧
1500Vac
1500Vac

Supplementary insulation≧
3000Vac
4000Vac

Leakage current
  Class Ⅰ≦
Handheld type  0.75m A
-

other 3.5m A
Leakage current of ground
300uA

Leakage current of case
100uA

Class Ⅱ≦
250&mu;A
Leakage current of case
100uA

Number of fuse
Class Ⅰ
Lx1
Lx1 , Nx1

Class Ⅱ
Lx1

Operating Temperature
By manufacture defined
≧ 40 ℃

	Series name		Output Voltage & Output type			Option for Screw Terminal
	AOCH10	-	5	S	-	A2
AC-DC ITE, Household, Switching Power start with A			5=5W	Single = S 5S Dual = D 5D or 5S12S Triple = SD 5S12D		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

Subjects		IEC60950-1	IEC60601-1
Creepage distance/Clearance distance	Basic insulation≧	2.5mm / 2mm	4mm / 2.5mm
Workingvoltage:250Vrms(Max.)	Supplementary insulation≧	5mm / 4mm	8mm / 5mm
Electric strength test	Basic insulation≧	1500Vac	1500Vac
Electric strength test	Supplementary insulation≧	3000Vac	4000Vac
Leakage current	Class Ⅰ≦	Handheld type 0.75m A	-
		other 3.5m A	Leakage current of ground	300uA
		other 3.5m A	Leakage current of case	100uA
	Class Ⅱ≦	250μA	Leakage current of case	100uA
Number of fuse	Class Ⅰ	Lx1	Lx1 , Nx1
Number of fuse	Class Ⅱ	Lx1	Lx1
Operating Temperature		By manufacture defined	≧ 40 ℃