22 Battery
22.4 Battery Handling
347
FX3G Series Programmable Controllers
User's Manual - Hardware Edition
21
Memory
Cassette
22
Battery
A
Special Devices
(M8000-,D8000-)
B
Instruction List
22.4 Battery Handling
When the battery voltage is low, a "ALM" LED lights (red) while the power is ON, and M8005 and M8006 are
switches ON.
Although the battery will continue to function for approximately 1 month after the "BATT" LED switches ON, a
replacement battery should be ordered and installed as soon as possible.
22.4.1 Battery life and replacement guidelines
FX3U-32BL battery life : Approx. 5 years (ambient temperature : 25 C(77 F))
[Guarantee period: 1 year after delivery or 18 months after
production]
The life of the battery changes with respect to ambient temperature.
When planning for battery replacement, please estimate the battery
life according to the graph to the right and order the replacement
batteries in advance.
22.4.2 Reading the date of manufacture
How to read the battery lot number (reference)
22.4.3 Special "battery low-voltage" device & notification program example
Prepare a system which allows constant external monitoring of the battery status, using an indicator lamp,
etc.
• M8005
Y001 is output when a battery low-voltage condition occurs.
• M8006
Battery low-voltage is latched.
• D8005
Battery voltage can be monitored.
7
010 4020 30 50
0
1
6
5
4
3
2
Bttery Life(years)
Ambient temperature( C)
Battery life vs. temperature
FX
3U
-32BL
LOT.44
Connecto
Year (Example: 2004)
Last digit of calendar
year
L OT.4 4
Model name
Month (Example: Apr)
1 to 9 : Jan to Sept.
X : Oct, Y : Nov, Z : Dec
Nameplate
............
M8005
Battery low-voltage
Y001