Mitsubishi Q2ACPU User Manual page 262

16. POWER SUPPLY MODULE
POINT
*1 Overcurrent protection
(a) The overcurrent proctector 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.
(b) When this device is activated, eliminate probable causes such as
insufficient current capacity or short circuit, and then start the system.
When the current has reached the normal value, the system will start
from the first.
*2 Overvoltage protection
The overvoltage protector shuts off the 5VDC circuit and stops the system if
overvoltage of 5.5 to 6.5V is applied to the circuit.
The power supply module LED turns OFF. When restarting the system,
switch the input power OFF, then back ON. The system is started up with an
initial start. 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 allowable momentary power failure period of PLC CPUs varies
depending on the power supply module used.
In the system using the A63P, it is the time from when the primary side of
the stabilized power supply supplying 24VDC to the A63P turns OFF until
the voltage (secondary side) has dropped from 24VDC to the specified
value (15.6VDC) or less.
*4 Inrush current
If power is reapplied immediately after power OFF (within 5 seconds), an
inrush current exceeding the specified value may flow (for 2ms or less).
Therefore, before reapplying power, make sure that 5 seconds have
elapsed after power off.
When selecting a fuse or breaker for an external circuit, consider the above
as well as meltdown and detection characteristics.
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