Power Supply PS1000-A6-24.10
Application Notes
20
21
-1
1
41
26.7
Parallel Use for Redundancy
1+1 Redundancy
Devices can be paralleled for redundancy to gain higher system availability. Redundant
systems require a certain amount of extra power to support the load in case one device fails.
The simplest way is to put two devices in parallel. This is called a 1+1 redundancy. In case
one device fails, the other one is automatically able to support the load current without
any interruption. It is essential to use a redundancy module to decouple devices from each
other. This prevents that the defective unit becomes a load for the other device and the output
voltage cannot be maintained any more.
Pay attention that leakage current, EMI, inrush current, harmonics will increase when using
multiple devices.
Recommendations for building redundant power systems:
•
Use separate input fuses for each device.
•
Monitor the individual devices. Therefore, use the DC-OK signal of the device.
•
It is desirable to set the output voltages of all devices to the same value (± 100mV)
or leave it at the factory setting.
N+1 Redundancy
Redundant systems for a higher power demand are usually built in a N+1 method.
E.g. four devices, each rated for 10A are paralleled to build a 30A redundant system.
Pay attention that leakage current, EMI, inrush current, harmonics will increase when using
multiple devices.
Restrictions
•
Keep an installation clearance of 15mm (left / right) between two devices and avoid
installing the devices on top of each other.
•
Do not use devices in parallel in mounting orientations other than the standard mounting
orientation or in any other condition, where a reduction of the output current is required.
Wiring examples:
Figure 26.7 Wiring for 1+1 redundancy with the redundancy module
Max.
10A
Load
Load
Share
Warning
I
opt
iona
l
Power
Supply
24V, 10A
+ +
- -
L N PE
Output
Input
DC-
OK
o
o
I
YR20.246
Redundancy
Module
Output
1
Input
2
Input
+
+
-
-
+
-
Load Share
OK
o
o
Redudnadcy
OK
o
o
Failure
Monitor
Power
Supply
24V, 10A
+ +
- -
L N PE
Output
Input
DC-
OK
o
o
+
-
PE
PS1000-D2-
24.20.RM
