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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
(Note)
 will 
cause 24VDC down to be detected, but operation will continue. 
(b)   An instantaneous power failure lasting in excess of 10ms
(Note)
 
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 
than 24VDC. 
(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.