11
MAINTENANCE AND INSPECTION
11.5 When Battery Has Gone Flat During Storage of Programmable Controller
11 - 35
9
EMC AND LOW
VOLTAGE
DIRECTIVES
10
LOADING AND
INSTALLATION
11
MAINTENANCE AND
INSPECTION
12
TROUBLESHOOTING APPENDICES INDEX
11.5 When Battery Has Gone Flat During Storage of Programmable
Controller
When the programmable controller is to be used after being stored for some period of time
and the battery has gone flat during storage, the memories in the CPU module and
memory card may be corrupted.
Hence, before resuming operation, always clear the memory of CPU module and format
the SRAM card using GX Developer.
After formatting the memories, write the memory contents backed up prior to storage to
each memory.
Remark
For the Universal model QCPU, when the latch data backup function (to standard
ROM) is used, data will not be disappeared even if a battery life ends, since latch
data such as device data of the CPU module or error history can be backed up
without using a battery.
The relationships between battery and battery-backed memorie are shown in Table11.15.
: Battery backed, : Not battery backed
* 1: As a battery, the Q6BAT, Q7BAT and Q8BAT are available.
* 2: The Universal model QCPU needs no battery backup.
* 3: Not available for the Basic model QCPU.
Format the battery-backed memories in Table11.15 using GX Developer before resuming
operation.
For information about the memory formatting, refer to the manual below.
GX Developer Operating Manual
Table11.15 Relationships between the battery and battery-backed memories
Memory
Battery
Battery of QCPU
Module
*1
Battery Built in Memory
Card
CPU module
Program memory
*2
Standard RAM
Standard ROM ---- (Battery backup not needed)
Memory card
*3
SRAM card
Flash card ---- (Battery backup not needed)
ATA card ---- (Battery backup not needed)