Mitsubishi Electric Q172DCPU User Manual page 51

2 SYSTEM CONFIGURATION
POINTS
(Note-3) : Allowable momentary power failure period
(1) For AC input power supply
(a) An instantaneous power failure lasting less than 20ms will cause
AC down to be detected, but operation will continue.
(b) An instantaneous power failure lasting in excess of 20ms may
cause the operation to continue or initial start to take place
depending on the power supply load.
Further, when the AC supply of the AC input module is the same
as that of the power supply module, it prevents the sensor
connected to the AC input module, which is ON at power-off,
from turning OFF by switching off the power supply.
However, if only the AC input module is connected to the AC line,
which is connected to the power supply, detection of the AC
down for the power supply module may be delayed by the
capacitor in the AC input module. Thus, connect a load of
approx. 30mA per AC input module to the AC line.
(2) For DC input power supply
(a) An instantaneous power failure lasting less than 10ms
cause 24VDC down to be detected, but operation will continue.
(b) An instantaneous power failure lasting in excess of 10ms
may cause the operation to continue or initial start to take place
depending on the power supply load.
(Note) : This is for a 24VDC input. This is 10ms or less for less
(Note-4) : Inrush current
When power is switched on again immediately (within 5 seconds) after
power-off, an inrush current of more than the specified value (2ms or
less) may flow. Reapply power 5 seconds after power-off.
When selecting a fuse and breaker in the external circuit, take account
of the blow out, detection characteristics and above matters.
then 24VDC.
2 - 30
(Note)
will
(Note)