Special Relay For Low Battery Voltage - Mitsubishi Electric FX5U User Manual

3.
Extract the old battery from the battery holder ("B" in figure below), and disconnect the battery connector ("C" in figure
below).
B
4.
Install the new battery. (Page 116 Battery attachment)
5.
Attach the expansion board connector cover. If an expansion board was removed in step 2, reinstall it.
• After replacing the battery, check whether the devices set by the latch and clock data are backed up
correctly, confirm safety, and then run the PLC.
• If the devices set by the latch are not backed up correctly, clear them, and set their initial values and clock
data again if necessary.
Reading the date of manufacture
How to read the battery lot number
Nameplate
Type
LOT
1 4 X
Month (Example: October):
1 to 9 = January to September,
X = October, Y = November, Z = December
Year (Example: 2014): Last two digits of year

Special relay for low battery voltage

Prepare a system which allows constant external monitoring of the battery status, using a GOT, etc.
• SM52 (SM8005)
The special relay turns ON when the battery voltage is the specified value or less.
The special relay turns OFF when the battery voltage is normal.
SM52(SM8005)
Battery low-voltage
• SM51 (SM8006)
The special relay turns ON when the battery voltage is the specified value or less.
The special relay stays ON even when the battery voltage is normal.
• SD8005
Battery voltage can be monitored.
C
Connector
FX3U-32BL
LOT.14X
............
Y1 Y1 is output when a battery low-voltage condition occurs.
8 MAINTENANCE AND INSPECTION
8.3 Battery
8
119