Parallel Connection For Redundancy - Siemens SITOP PSU100C 6EP1321-5BA00 Operating Instructions Manual

9.2

Parallel connection for redundancy

Connecting several SITOP PSU100C power supplies in parallel for redundancy purposes is
required if especially high demands are placed on the availability of a reliable 24 V power
supply.
Using the SITOP PSE202U redundancy module, two 24 V power supplies of the same type
can be decoupled (Figure 9-2 Redundant configuration (Page 49)). When one of the devices
fails, then the other automatically takes over the power supply. If one of the power supplies
fails, then this is signaled using an LED on the redundancy module as well as an isolated
relay contact.
When dimensioning the system, it must be ensured that n+1 redundant connected power
supplies can handle the total power requirement of the remaining n power supplies.
Note
For a high reliability of the supply, it is recommended that the redundant switched power
supplies are protected separately on the line-side and, if possible, be connected to different
power supply networks.
Note
The SITOP PSE202U NEC Class 2 (6EP1962-2BA00) redundancy module must be used to
create a redundant circuit configuration according to NEC Class 2 (Figure 9-3 Parallel
connection with redundancy module for NEC Class 2 (Page 50)).
Figure 9-2
SITOP PSU100C
Operating Instructions, 06.2013, C98130-A7599-A1-2-7629
Redundant configuration
9.2 Parallel connection for redundancy
Applications
49