Siemens S5-135U/155U System Manual page 107

Replacing the
The lithium battery can be replaced without memory loss if the PSU is
Lithium Battery
switched on, the rechargeable battery is in order or you apply an external
(4.5 V) voltage to the "Ext.Batt." terminals.
How to Replace Replace the lithium battery in the following steps:
the Lithium Battery
Replacing a Fan
Location of the The three fans are situated at the bottom of the power supply unit and can be
Fans
individually replaced during operation.
Before
If you operate your power supply with a filter, you must first release the filter
Replacement
subdrawer and pull it out before you can replace a fan (see Section entitled
"Replacing the Filter Mat").
System Manual
C79000-G8576-C199-06
Central Controllers and Expansion Units Power Supply Units
Step
Slide the battery compartment cover down.
1
2 Pull the battery compartment out.
Remove the old lithium battery from the battery compartment by inserting a
3
screwdriver through a hole in the compartment base to push the battery
upwards.
Insert the new lithium battery in the battery compartment
4
Important:
Ensure correct polarity.
Slide the battery compartment in.
5
Close the cover.
6
Press the Reset button.
7
Result (only with PSU on):
– "MB low" LED goes off.
– Contacts 14 and 15 of the
Battery Warning relay are bridged.
Action
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