Siemens S5-135U/155U appendix Central Controllers and Expansion Units Power Supply Units

Models: S5-135U/155U

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Central Controllers and Expansion Units Power Supply Units

Setting the Backup As of Version 6 of PSU 6ES5 955-3NA12, you can set jumper RR-LL to

Battery Monitor choose whether the signaling relay (monitor output) should switch in the

event of battery failure as well as fan failure:

SJumper RR-LL open (state when delivered): relay will signal only a fan failure

SJumper RR-LL closed: relay will signal a fan and battery failure.

If the backup voltage fails or a fan is at standstill, or in both cases, the signaling relay will drop out (monitor output). The ªBatt. Lowº LED will also light up.

SRelay contacts 2-1 closed: battery backup voltage in order and fan running

SRelay contacts 2-3 closed: backup voltage under 2.7 V or fan failure

Note

The signaling relay in the power supply unit will drop out in the event of a fan fault or backup battery fault. The user's circuitry for the signaling relay must therefore be suitable for both types of fault.

If the signaling relay drops out because of a backup battery fault and the programmable controller is therefore switched off, the program in the main memory may be lost. Loss of program can be avoided if an external backup voltage (3.4 V) is present at the sockets on the front plate of the power supply unit during shutdown of the programmable controller.

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System Manual

C79000-G8576-C199-06

Page 128
Image 128
Siemens S5-135U/155U appendix Central Controllers and Expansion Units Power Supply Units