SMC Networks EX250-SEN1, Operation Manual

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No.EX##-OMK0004-A
Trouble No.5
Trouble Possible cause Investigation method of cause Remedy
Failure of the power
supply for the input
and control of the SI
unit.
Check the supply voltage to the power
supply for the input and control of the SI
unit. Supply 24 VDC
±
10% to the
power supply for the input
and control.
Incorrect connection
between the SI unit
and input block
Check that the bolt joining the SI unit and
Input block has not loosened.
Tighten the bolts by hand so
that there is no gap between
the SI unit and Input block.
Tighten at the specified
torque.
(Tightening torque: 0.6 Nm)
The Input block fuse
has melted Check if the fuse of the input block has
melted.
Remove the cause of the
short-circuit and replace the
fuse with new one.
Intrusion of liquids
such as water Check that unused connectors of the Input
block are plugged with waterproof caps.
If liquid such as water has
got into the input, replace the
Input block with new one.
The Input
block
PWR_LED
goes off.
Input block failure
Replace the Input block with new one and
operate to check the normal operation
recovers.
Replace the Input block with
new one.
Trouble No.6
Trouble Possible cause Investigation method of cause Remedy
Inconsistent polarity
in sensors Check the specifications of the Input block
(NPN, PNP) match those of the sensor. Make a suitable combination
of Input block and sensor.
Incorrect connection
of the sensor
Check that the sensor cable is not broken
and that the connection between the sensor
cable and connector has not loosened.
Review the connection
condition of the sensor cable.
(If the cable is broken,
replace it with new one.)
Only the input
signal LED of
the Input block
do not lights
up
Sensor failure Check the troubleshooting of the sensor.
Correct the trouble of the
sensor.
Trouble No.7
Trouble Possible cause Investigation method of cause Remedy
Check that the power supply cable for the
input and control is not broken, and that the
connection between the power supply cable
and connector has not loosened. Review the connection
condition of the power supply
cable. (If the cable is broken,
replace it with new one.)
Incorrect wiring of the
power supply for the
input and control
Check that there is no incorrect wiring of
the power supply cable. Review the wiring condition
of the power supply cable.
The SI unit
PWR_LED
goes off.
Failure of the power
supply for the input
and control
Check the supply voltage to the power
supply for the input and control.
Supply 24 VDC
±
10% to the
power supply for the input
and control.