Siemens SITOP PSU400M, Manual

Page: 49 / 58

Applications
9.2 Parallel connection for redundancy
SITOP PSU400M
Manual, 05.2018, C98130-A7601-A1-5-7629
49
9.2 Parallel connection for redundancy
Connecting several 24 V power supplies in parallel for redundancy purposes is required if
especially high demands are placed regarding the availability of a reliable 24 V power
supply.
Using the SITOP PSE202U redundancy module, two power supplies of the same type up to
20 A can be decoupled (Figure 9-2 Redundant configuration with two power supplies and
SITOP PSE202U redundancy module (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 fused separately on the line-side and, if possible, be connected to different line
supplies.
Figure 9-2 Redundant configuration with two power supplies and SITOP PSE202U redundancy
module
You can find additional information at:
SITOP PSE202U manual (
https://support.industry.siemens.com/cs/ww/en/view/42248598 )