ABB AC 900F Mounting And Installation Instructions Manual page 62

TA 951F battery for RAM buffering
Use
The TA 951F lithium battery serves to supply the real time clock and the SRAM in
order to save the memory contents (e.g. process and configuration data) in the event
of power failure.
The CPU module is delivered without lithium battery. A new TA 951F battery must
always be inserted during initial start-up of the CPU module.
After longer voltage supply interruptions at the CPU module (maintenance
operations, shut-down, transport or similar), a new battery must be installed as well
in order to ensure the specified buffering times.
Although the CPU module can also be operated without battery its use is strictly
recommended in order to avoid data loss.
The CPU module monitors the battery voltage and thus indirectly also the battery
capacity (charging status). The "Low CPU module battery capacity" message is
issued when the capacity has reached a level that is sufficient for 14 days buffering.
The battery should be replaced at regular intervals and as soon as possible after the
low battery warning has been displayed.
The TA 951F lithium battery is the only battery type that is compatible with the PM
CPU module. It is a non-rechargeable primary cell.
The battery must only be replaced with the controller supply voltage ON in order
to avoid any data loss.
Data buffering is not possible without a battery when the supply voltage is
switched off.
Safety instructions
Risk of overheating and subsequent explosion!
Batteries must not be short-circuited, recharged, opened or thrown
into fire!
B
Store the batteries in a dry place.
Strictly observe the applicable local recycling and environmental
regulations during disposal of used batteries.
62
Section 4 Accessories
M&I – AC 900F Controller