Omron CV500 Installation Manual page 106

Error Processing and Correction
Input Units
Symptom
Not all inputs turn ON or in-
dicators are not lit. di li
Not all inputs turn ON (indi-
cator lit).
Not all inputs turn OFF.
Specific bit does not turn
ON. ON
Specific bit does not turn
OFF. OFF
Input irregularly turns ON/
OFF.
Error occurs in units of 8
points. i
Input indicator is not lit in
normal operation.
Cause
(1) Power is not supplied to Input Unit.
(2) Supply voltage is low.
(3) Terminal block mounting screws are
loose.
(4) Faulty contact of terminal block con-
nector.
Input circuit is faulty.
Input circuit is faulty.
(1) Input device is faulty.
(2) Input wiring disconnected.
(3) Terminal block screws are loose.
(4) Faulty terminal block connector con-
tact.
(5) Too short ON time of external input.
(6) Faulty input circuit
(7) Input bit number is used for output in-
struction.
(1) Input circuit is faulty.
(2) Input bit number is used for output in-
struction.
(1) External input voltage is low.
(2) Malfunction due to noise.
(3) Terminal block screws are loose.
(4) Faulty terminal block connector con-
tact.
(1) Common terminal screws are loose.
(2) Faulty terminal block connector con-
tact.
(3) Faulty data bus
(4) Faulty CPU
Faulty indicator
Remedy
Supply power
Adjust supply voltage to within rated range.
Tighten screws.
Replace terminal block connector.
Replace Unit.
Replace Unit.
Replace input devices.
Check input wiring
Tighten screws
Replace terminal block connector.
Adjust input device
Replace Unit.
Correct program.
Replace Unit.
Correct program.
Adjust external input voltage to within rated
range.
Protective measures against noise, such
as:
(1) Install surge suppressor.
(2) Install insulation transformer.
(3) Install shielded cable.
Tighten screws
Replace terminal block connector.
Tighten screws
Replace terminal block connector.
Replace Unit.
Replace CPU.
Replace Unit.
Section 5-3
93