Instruction manual

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2 SYSTEM CONFIGURATION
POINTS
(Note-1): Overcurrent protection
The overcurrent protection device shuts off the 5V, 24VDC circuit and
stops the system if the current flowing in the circuit exceeds the specified
value.
The LED of the power supply module is turned off or lights up in dim
green when voltage is lowered. If this device is activated, switch the input
power supply off and eliminate the cause such as insufficient current
capacity or short. Then, a few minutes later, switch it on to restart the
system.
The initial start for the system takes place when the current value
becomes normal.
(Note-2): Overvoltage protection
The overvoltage protection device shuts off the 5VDC circuit and stops
the system if a voltage of 5.5VDC or more is applied to the circuit.
When this device is activated, the power supply module LED is switched
OFF.
If this happens, switch the input power OFF, then a few minutes later ON.
This causes the initial start for the system to take place. The power supply
module must be changed if the system is not booted and the LED
remains OFF.
(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.