Maintenance; Replacing The Backup Battery - Siemens S5-155U System Manual

6ES5 955-3NA12 Power Supply Unit
4.5.5

Maintenance

Replacing the backup
battery
Battery submodule
4 - 78
Caution
Incorrect replacement of the battery can result in explosion
hazard. It should only be replaced by the same type or an
equivalent type recommended by the manufacturer. Used
batteries should be disposed of according to the manufacturer's
instructions.
You can replace the backup battery without loss of data if the power
supply unit is switched on, or if you apply an external voltage (3.4 V)
at the "Ext. Batt." sockets. The backup battery must be replaced every
3 years at the latest, irrespective of memory configuration and backup
operation. Replace the battery as follows:
Step Action
1 Pull the cover downwards.
2 Pull the battery submodule forwards and out, and
remove it.
3 Replace the battery.
4 Ensure correct polarity.
5 Once the new battery is fitted and system voltage is On,
press the Reset button on the power supply unit.
Only use battery submodules of order number 6XG3 400-2CK00!
+
S o c k e t s f o r E x t e rn a l
B a c k u p Vo l t a g e
Battery
S u b m o d u le
*
Co ve r
C79000-B8576-C199-03
System Manual