6-15
6 Troubleshooting
CP1E CPU Unit Hardware User’s Manual(W479)
6-2 Troubleshooting Unit Errors
6
6-2-1 Inputs
6-2 Troubleshooting Unit Errors
This section describes how to troubleshoot errors that occur in devices other than the CP1E CPU
Unit.
6-2-1 Inputs
No. Symptom Cause Remedy
1
Not all inputs turn ON or
indicators are not lit.
1. External power is not supplied for the
input.
Supply power.
2. Supply voltage is low. Adjust supply voltage to within
rated range.
3. Terminal block screws are loose. Tighten screws.
2
Not all inputs turn ON
even though the indicator
is lit.
Input circuit is faulty. (There is a short at
the load or something else that caused an
overcurrent to flow.)
Replace Unit.
3
Not all inputs turn OFF. Input circuit is faulty. Replace Unit.
4
Specific input bit does not
turn ON.
1. Input device is faulty. Replace input devices.
2. Input wiring disconnected. Check input wiring
3. Terminal block screws are loose. Tighten screws.
4. Too short ON time of external input. Adjust input device.
5. Input circuit is faulty. Replace Unit.
6. Input bit number is used for output
instruction.
Correct the ladder program.
5
Specific input bit does not
turn OFF.
1. Input circuit is faulty. Replace Unit.
2. Input bit number is used for output
instruction.
Correct the ladder program.
6
Input irregularly turns
ON/OFF.
1. External input voltage is low or unsta-
ble.
Adjust external input voltage to
within rated range.
2. Malfunction due to noise. Take protective measures
against noise, such as:
• Install surge suppressor.
• Install insulation transformer.
• Install shielded cables between
the Input Unit and the loads.
3. Terminal block screws are loose. Tighten screws.
7
Error occurs in units of 8
points or 16 points, i.e.,
for the same common
1. Common terminal screws are loose. Tighten screws.
2. Faulty data bus Replace Unit.
3. Faulty CPU Replace CPU Unit.
8
Input indicator is not lit in
normal operation.
Faulty indicator or indicator circuit. Replace Unit.
To Next Page
Loading...
