User`s manual

Maintenance and inspection Battery life and replacement procedure
10 – 16
10.3.2 Replacement procedure of the CPU module battery
The battery of the CPU types Q00J, Q00 and Q01 are mounted on the front side of the module.
All other CPU types have a case on the bottom side of the CPU (also refer to section 5.2.2).
The programmable controller power must be on for 10 minutes or longer before dismounting the
battery, so that the capacitor is sufficiently charged for backing up the memory data during bat-
tery replacement.
After replacing a battery, write the date for next battery replacement on the sticker on the back
side of the front cover. Write the proper date by checking the battery life.
NOTES
Data in the memory are backed up for 3 minutes max. by a capacitor even after the battery is
removed. The replacement of the battery should be done during this time.
Back up the data in the CPU module by a PC before starting replacement.
When replacing a battery of a Redundant CPU, back up the memory data such as programs
by the memory copy from the control system to the standby system.
Do a manual system switching by the programming software GX Developer or GX IEC
Developer and replace the CPU battery of the former control system afterwards.
For the memory copy from control system to standby system and system switching function,
refer to the User's Manual of the Redundant System.
Fig. 10-2: Label for notes of the date for next battery replacement on the back side of the front
cover
Label for notes