22 Battery
22.1 Battery Purpose
345
FX3G Series Programmable Controllers
User's Manual - Hardware Edition
21
Memory
Cassette
22
Battery
A
Special Devices
(M8000-,D8000-)
B
Instruction List
22. Battery
The battery is not incorporated in the PLC main unit at shipment from the factory.
Order it if necessary.
22.1 Battery Purpose
The battery backs up the following contents against power interruption.
Proper parameter setting is required to back up the device memory and current time.
→ For the parameter setting method, refer to Section 22.3.
*1. The data is backed up by the large-capacity capacitor built in the PLC at shipment from the factory.
→ For backup by the capacitor, refer to Section 4.5.
22.2 Specifications
STARTUP AND MAINTENANCE
PRECAUTIONS
• Make sure to connect the battery for memory backup correctly.
Do not charge, disassemble, heat, short-circuit, or expose the battery to fire.
Doing so may rupture or ignite it.
STARTUP AND MAINTENANCE
PRECAUTIONS
• Turn off the power to the PLC before attaching or detaching the following devices.
Failure to do so may cause equipment failures or malfunctions.
- Peripheral devices, expansion boards, and special adapters
- Extension units/blocks and FX Series terminal blocks
- Battery and memory cassette
TRANSPORTATION PRECAUTIONS
• When transporting the FX3G Series PLC incorporating the optional battery, turn on the PLC before shipment, confirm that the battery
mode is set using a parameter and the ALM LED is OFF, and check the battery life.
If the PLC is transported with the ALM LED on or the battery exhausted, the battery-backed data may be unstable during
transportation.
Item Data Retained By Backup Battery
Device memory
Auxiliary relay M1536 to M7679, state S1000 to S4095, data register D1100 to D7999,
extended register R0 to R23999
Current time
*1
Current time clock
Item Specifications Remarks
Nominal voltage 3V Battery voltage can be monitored with PLC data register D8005.