Operation Processing During Momentary Power Failure - Mitsubishi Q00JCPU User Manual

3
SEQUENCE PROGRAM CONFIGURATION AND
EXECUTION CONDITIONS

3.6 Operation Processing during Momentary Power Failure

When the input voltage supplied to the power supply module drops below the specified
range, the CPU module detects a momentary power failure and performs the following
operation.
(1) When momentary power failure occurs for a period shorter than the
3
- 68 3.6 Operation Processing during Momentary Power Failure
permitted power failure time
The output is maintained when the momentary power failure occurs, and error history
are logged. Then the system interrupts the operation processing.
(The timer clock continues.)
(a) When resume start is specified for the SFC program
When a resume start is specified for the SFC program, the system is saved.
(b) When recovered from momentary power failure
When a momentary power failure ends, the operation processing is resumed.
(c) Watchdog timer (WDT) measurement during momentary power failure
Even if the operation is interrupted due to momentary power failure, the watchdog
timer (WDT) measurement continues. For example, if the GX Developer PLC
parameter mode WDT setting is set at 200 ms, when a momentary power failure
of 15 ms occurs at scan time 190 ms, the watchdog timer error is set.
Figure 3.57 Operation during momentary power failure
Momentary power
failure occurrence
Power recovery
END 0 END 0
CPU module interrupts
the operation.
END