Mitsubishi Q01CPU User Manual page 317

11
MAINTENANCE AND INSPECTION
SRAM card
Q3MEM-8MBS
Power-on
*1
time ratio
0%
30%
50%
70%
100%
* 1: The power-on time ratio indicates the ratio of programmable controller power-on time to one day
(24 hours).
(When the total power-on and power-off times are 12 hours for each, the power-on time ratio is
50%).
* 2: The manufacturing control number (the third digit from the leftmost) is written on the label on the
back of the SRAM card (as shown in Diagram 11.6).
* 3: Indicates the battery life when the SRAM card is installed in the High Performance model QCPU
whose first 5 digits of the serial number are "04012" or higher.
For the battery life for those of "04011" or lower, refer to Appendix 2.
* 4: The actual value may vary depending on ambient temperature.
POINT
1. Do not use the battery exceeding its guaranteed life.
2. When the battery hours (total power failure time) may exceed its guaranteed
value, take the following measure.
• Perform ROM operation to protect a program even if the battery dies at
the programmable controller power-OFF.
• Back up programs and data after SM52 turns on (within the backup time
after alarm occurrence).
3. Note that the SRAM card battery is consumed even while the programmable
controller is powered ON with the CPU module battery connected.
4. When the special relay showing battery low, SM52 turns on, immediately
change the battery.
Even if an alarm has not yet occurred, it is recommended to replace the bat-
tery periodically according to the conditions of use.
5. The SRAM card is not available for the Basic model QCPU.
Battery life
Actual service
Guaranteed value
value (Reference
(MIN)
value)
36,300hr 43,800hr
4.1years 5.0years
43,800hr 43,800hr
5.0years 5.0years
43,800hr 43,800hr
5.0years 5.0years
43,800hr 43,800hr
5.0years 5.0years
43,800hr 43,800hr
5.0years 5.0years
Manufacturer
control number
Diagram 11.6 Label on the back of SRAM card
11.3 Battery Life and Replacement Procedure
11.3.4 SRAM card battery life
*3
After SM52
turns ON.
(Power failure
*4
compensation time
after alarm)
50 hr
50 hr
50 hr
50 hr
50 hr
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