Opto Troubleshooting

This page is dedicated to troubleshooting of the Opto22 system. Additions to this page should be made in a Symptom/Solution-style. The goal is to provide a 'first place to look'-list for other Opto users and help minimise downtime.

Opto Brains

3 Volt Fault

Symptom
The LED indicating a 3 Volt fault is on and the Opto unit can't be communicated with. Resetting the IP manually (see Brain manual) is also not possible in this state.
Solution
Use a multimeter and check the 5V supply voltage to the rail; the Opto brains require 5V DC (+/-0.1V). If it's found that the supplied voltage is below 4.9V, adjust the output of the power supply (if possible). As a check, test the 'broken' power supply on a working Opto brain to confirm that it is indeed the power supply that has failed and not a short in the brain.