Siemens S5-135U/155U System Manual page 97

Starting up with a
Lithium Battery
When do you Whether or not you require a lithium battery depends on what type of backup
Require a Lithium
you require for your system. The following table will help you to decide.
Battery?
You require long backup times and do not want to
supply an external backup voltage,
You require redundant backup and do not want to
supply an external backup voltage,
Short backup times are sufficient,
You do not require redundant backup,
The lithium battery must be ordered separately (see Ordering Information).
Notes Relating to The backup battery (type C) contains lithium (more than 0.5 g) and is
the Lithium Battery
delivered separately from the power supply unit, because of special shipping
regulations.
Depending on the manufacturer, the battery's plus pole may have a protective
cover. You must remove this cover before you place the battery in the battery
compartment.
Caution
!
Improper replacement of the battery can result in the danger of explosion.
If should only be replaced by the same type or an equivalent one
recommended by the manufacturer. Used batteries should be disposed of
according to the manufacturer's instructions.
The backup battery must be fitted before the programmable controller is
started up. Without a backup voltage, the PLC will remain in the Stop state
after system voltage is switched on.
Only use battery compartments marked -A1155-B21 (red label).
How to Fit the Fit the lithium battery in the following steps:
Lithium Battery
System Manual
C79000-G8576-C199-06
Central Controllers and Expansion Units Power Supply Units
IF...
Step
1 Slide the battery compartment cover (A) downwards.
2 Pull the battery compartment (B) out.
3 Insert the lithium battery in the battery compartment.
Important: Ensure correct polarity.
4 Slide the battery compartment in.
5 Close the cover.
THEN...
you need a lithium battery.
you need a lithium battery.
you do not need a lithium
battery.
you do not need a lithium
battery.
Action
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