Maintenance
7-3
AutomationSystem S7-400 Hardwareand Installation
A5E00850741-01
Using Backup Batteries
Youshould change the backup battery once a year.
Observe the usual regulations/guidelines for disposing of lithium batteries in your
country.
Backup batteries should be stored in a cool, dry place.
Backup batteries can be stored for ten years. If they are stored for a longer period,
however,a passivation layer may form.
Rules for the Care of Backup Batteries
Youmust observe the following rules to avoid hazards in the care of backup
batteries:
!Warning
Risk of injury,material damage, release of hazardous substances.
Lithium batteries can explode if handled improperly.Their improper disposal may
result in the release of hazardous substances. Strictly adhere to the following in-
structions:
•Do not throw a new or low battery into an open fire and do not perform any sol-
dering work on the cell casing (max. temperature 100 °C). Do not recharge the
battery --risk of explosion! Do not open a battery. Replace a faulty battery onoly
with the same type. Replacement batteries can be ordered from SIEMENS (for
order numbers, refer to the “Module data” reference manual, in appendix C).
This will insure that your are installing a short circuit-proof type.
•Always try to return low batteries to the manufacturer or deliver these to a regi-
stered recycling company.