OPTO 22 Modular M4RTU, User Manual

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76 M4RTU/M4 I/O User’s Guide
TROUBLESHOOTING
Table A-1: M4RTU/M4 I/O Troubleshooting Chart (continued)
Indication Condition/Problem Action
Digital input is not working. Input device is not working
properly.
Wrong module type.
Voltage on input is not
compatible with module voltage
range.
I/O or processor board is bad.
Check input device wiring and power source. Rewire,
replace, or fix power source as needed.
Make sure module is 5V (for example, [G4IDC5 is
correct, G4IDC24] is incorrect).
Change voltage to match module or module to match
voltage.
Use G4SWIN module and OptoControl or G4TEST to
send commands to the M4RTU/M4 I/O to verify that the
processor board and I/O board are working properly.
Digital input test with
G4SWIN module installed.
I/O or processor board is bad. Contact Opto 22 Product Support (see Appendix G).
Analog output is not working. Output is wired incorrectly.
Device is not properly matched
to module type.
I/O or processor board is bad.
Check wiring to output device. Test module using meter
and test software (OptoControl or G4TEST). Change
voltage to match module or module to match voltage.
Contact Opto 22 if meter reading does not change with
value change in test software.
Analog input is not working. Voltage output device is wired
incorrectly.
Thermocouple has a break.
RTD has open or incorrect
wiring.
I/O or processor board is bad.
Check device and wiring. Connect voltage source or
current source (depending on input type) and use test
software to determine if input is functioning.
For a thermocouple, check for continuity across test
points next to module.
For an RTD input, check resistance across test points
next to module.
Contact Opto 22 Product Support if any of the following
occurs:
- If value in test software does not change with input
when testing input voltage or current with test software.
- If thermocouple has continuity across test points.
- If resistance across test points is about 100 ohms for
RTD input.