Siemens Automation System S7-400 - Manual (Page 150)

Maintenance
7-2
Automation System S7-400 Hardware and Installation
A5E00850741-01
7.1 Replacing the Backup Battery
Replacing the Backup Battery
1. Discharge any static charge by touching a grounded metal part of the S7-400.
2. Open the cover of the power supply module.
3. Using the loop(s), pull the backup battery/batteries out of the battery
compartment.
4. Insert the new backup battery/batteries in the battery compartment of the power
supply module.
Ensure correct polarity of the battery/batteries.
5. Switch on battery monitoring with the BATT INDIC slide switch.
If You ... ...Then
have a single-width power supply module, set the BATT INDIC switch to
BATT.
have a double or triple-width power supply module
and want to monitor a backup battery,
set the BATT INDIC switch to
1BATT.
have a double or triple-width power supply module
and want to monitor both backup batteries,
set the BATT INDIC switch to
2BATT.
6. Press the FMR button.
7. Close the cover of the power supply module.
Note
If you store the batteries for a long period, a passivation layer may form. Please
read Section 6.8, Inserting a Backup Battery.