If you use the peak power supply products encountered problems, please give priority to search the following common problems can solve your problem. If the answers to the above questions are not available for you, please contact the nearest local distributor and our dealers will reply to you as soon as possible!

DingFeng-Power is a professional manufacturer for standard power supply, power supply products market demand to develop many kinds of. Select the appropriate power supply products in which the relevant specifications, electrical functions or product reliability is what you pay attention to. Therefore, the following common problems, please refer to!
 

Functional aspects

Q1

Is it possible to utilize 2 units of the HRP-600 in parallel

Ans
No, you can not do this connection because HRP-600 is not equipped with the parallel function. When two power supplies are connected in parallel, the one with higher output voltage will share more loading and deliver more (even "all") power to the load and cause these two power supplies to be unbalanced. We suggest using PSP-600 because it is equipped with the current sharing function.
Q2

If we need a 24V output power supply, can we use two 12V pow

Ans
YES, basically you can do this to get the right output voltage, but be careful that the rated output current of the series system should be the rating of the minimum one in these series connected power supplies. Furthermore, we like you to parallel a diode at the output of power supply to prevent possible damage of internal capacitors.
Q3

How do we choose a power supply to charge a battery?

Ans
DingFeng Power has ESC, SC, PA, PB series for battery charger purpose (120~360W). If these series does not meet customers' demands and they like to choose a power supply as a charger, we advice to pick up one which over load protection (OLP) mode is constant current limiting. The models in this mode provide constant current even when the protection circuit is triggered. The second choice is fold-back current limiting or constant wattage model. In this model, when a battery is running low, the output current of the power supply will gently increase. The level of increase depends on battery's capacity and degree of exhaustion. Hiccup or shut down model are not recommended because it will stop to generate current when OLP happens.
Q4

A few things you should know before using the Remote Sensing

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
Q5

How to select adaptors with the correct AC plug for use in d

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.

Q6

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.
Q7

Can DingFeng Power charger use on Lithium battery or other t

Ans
All DingFeng chargers are designed for lead-acid batteries. Every Lithium battery or other type of battery will have its own charging/discharging characteristic. Modification will be required for MW's charger in order to match the profile of each battery or users' requirements. Please contact your local distributor if you would like to have a modification for your own battery.
Q8

How to select a suitable proper circuit breaker or fuse for

Ans
At input side, there will be a large transient inrush current during the power on of an SPS. The inrush current is usually of 20~70A based on the design of SPS, which will last for 1/2~1cycle of AC input (ex. 1/120~1/60 seconds for 60Hz AC source). Every breaker or fuse will actually have its own time-current (V-I) characteristic curve. Users can choose a breaker or fuse which has a rated current just over input current of SPS and check whether the V-I curve of the breaker or fuse can withstand the high inrush current from the SPS with a maximum duration of 1 cycle of AC input (e.g. 1/60 second).
Q9

What should be noticed when installing a power supply in ver

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.
Q10

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. Generally, when we choose a suitable power supply, fan is not necessary if wattage is under 150W. Between 150~500W, both fan and fanless products are available. Above 500W, a fan is needed.
Q11

During the operation of your power supply, there is some lea

Ans
Due to the requirement of EMI, there will be some Y capacitors between line and neutral to the FG (case) to improve EMC. These Y capacitors will cause some leakage current flow from line or neutral to the case (normally case will be connected to earth ground). For example, IEC-60950-1 requires that this current should be less than 3.5mA for IT equipment, so basically the leakage current you find on the case will not hurt human body. Proper connection to Earth ground will solve the leakage current problem.
Q12

The output ground (GND) and frame ground (FG) is the same po

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.
Q13

Why I can not turn on the power supply smoothly when the loa

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.