Mitsubishi MELSEC-A A1SCPUC24-R2, User Manual

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38
POINT
*1 Overcurrent protection
The overcurrent proctection device shuts off the 5VDC and/or 24VDC circuit(s) and
stops the system if the current exceeding the specified value flows in the circuit(s).
As this results in voltage drop, the power supply module LED turns OFF or is dimly
lit.
After that, eliminate the causes of overcurrent, e.g., insufficient current capacity and
short circuit, and then start the system.
When the current has reached the normal value, the initial start up of the system will
be performed.
*2 Overvoltage protection
The overvoltage protection shuts off the 5VDC circuit and stops the system if the
overvoltage of 5.5 to 6.5V is applied to the circuit.
This results in the power supply module LED turning OFF.
When restarting the system, power OFF and ON the input power supply, and the
initial start up of the system will be performed.
If the system is not booted and the LED remains off, this means that the power
supply module has to be replaced.
*3 Allowable momentary power failure period
The programmable controller CPU allowable momentary power failure period varies
with the power supply module used.
In case of the A1S63P power supply module, the allowable momentary power failure
period is defined as the time from when the primary side of the stabilized power
supply for supplying 24VDC to the A1S63P is turned OFF until when the voltage
(secondary side) has dropped from 24VDC to the specified value (15.6VDC) or less.
*4 Inrush current
If the power supply module is re-powered ON right after powered OFF (within
5seconds), the inrush current exceeding the specified value (2ms or less) may be
generated. Therefore, make sure to re-power ON the module 5seconds after power
off.
When selecting a fuse or breaker for external circuit, consider the above point as
well as meltdown and detection characteristics.