User`s manual
Battery life and replacement procedure Maintenance and inspection
MELSEC System Q, Hardware 10 – 15
The manufacturer control number of the SRAM card is written on the label on the back of the
SRAM card. When character string including the manufacturer control number is 4 digits, the
third digit from the leftmost is the manufacturer control number.
● Q3MEM-BAT
Q2MEM-2MBS.jpg
Fig. 10-1: Indication of version of SRAM card
SRAM card
Power-on
time ratio
Battery life
Guaranteed value
Actual service
value
After SM52 turned on
Q3MEM-4MBS 0 % 43800 hours
(5 years)
43800 hours
(5 years)
50 hours
30 %
50 %
70 %
100 %
Q2MEM-1MBS
(Manufacturing
control No. B)
Q2MEM-2MBS
0 % 36300 hours
(4.1 years)
43800 hours
(5 years)
50 hours
30 % 43800 hours
(5 years)
50 %
70 %
100 %
Tab. 10-15:Battery life (Q3MEM-BAT)
Manufacturer control number (Version)
("A" in this example)