User`s manual

Power supply module specifications Specifications
MELSEC System Q, Hardware 12 – 59
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If the momentary power failure time is within the period given in the table above, the system detects an AC down
and suspends the operation processing. However, the system continues operations after the power comes back.
In the system operating with two redundant power supply modules, the system does not initially start operations
when the momentary power failure exceeding 20 ms occurs in only one of the input power supplies. The system,
however, may initially start operations when the momentary power failure exceeding 20 ms occurs simultane-
ously in both input power supplies.
Q64RP only (AC input power supply):
Supplying the same amount of AC to both the power supply module and the input module (such as QX10) can
prevent the sensor connected to the input module from being switched to the OFF status when the power supply
turns off.
Note, however, that if only the input module (such as QX10) is connected on the AC line, which is connected to
the power supply, an AC down detection in the power supply module may be delayed due to the internal capacitor
of the input module. To avoid this, connect a load of approx. 30 mA per input module on the AC line.
Q63RP only (DC input power supply):
The allowable momentary power failure period is the time when 24 V DC is input. If the input is less than 24 V DC,
the time will be shorter.)