-14-
TDK-Lambda
HWS1500 Series
INSTRUCTION MANUAL
5-11. Parallel Operation
Current balancing function is provided. There are 3 operation modes possible which is (A), (B) and (C).
(A)To Increase the Output Current
Current balancing function activates by connecting PC-to-PC terminal and COM-to-COM terminal, and output current
of each power supply is equivalently supplied to load. Wires to PC terminals shall be as short as possible, same length
and twisted.
There is a possibility that output could be unstable caused by external noise. For this case, disconnect COM terminal
and connect -S terminal from parallel power supply to a single point on the load. Please refer connection Method (A)-2.
1.
Adjust the output voltage of each power supply to be same value within 1% or 100mV, whichever is smaller.
2.
Use same length and type of wires for all load lines.
3.
Maximum value of output current in parallel is up to 80% of all paralleled models. The purpose of the current
balancing function is the static power-up. Therefore the output voltage might decrease according to the
condition of dynamic load. There might be a step in the rise waveform during parallel operation.
4.
Up to 5 units can be connected in parallel.
(B)To Use as a Backup Power Supply
1.
Set power supply output voltage higher by the forward voltage drop of diode.
2.
Adjust the output voltage of each power supply to be same value.
3.
Use within the specifications for output voltage and output power.
(C)In the case of parallel connections, it is possible to control the output voltage by adjusting the volume from only 1
unit. Choose 1 unit that would act as the master and this unit’s volume will determine the output voltage. The volume on
each slave units must be turned clockwise to maximum position. Then adjust the master volume to set the output voltage.
Connection for this application is shown in figure (c).
Method (B)
Power Supply
Load
Io
Vf
Vf
Vo
Vo+Vf
Vo+Vf
Output Power(W)=(Vo+Vf)
×
Io
+S
-
S
+S
-
S
PC
+S
-
S
-
S
PC
Load
Power Supply
+S
COM
COM
Method (A)-2
Method (A)-1
PC
+S
+S
-
S
-
S
PC
Load
Power Supply
COM
COM
Method (C)
Power Supply
Load
－
－
+S
+
-S
PC
COM
PV
REF
REF PV COM PC
－
+S
-S
