Good Morning! We are having issues with the dry contact relay and the exhaust fans again.
Contact relay # 5 that is solenoid 2 A isn’t coming on auto or manual. When you put it on all the light go dim.
If turning on the exhaust fans causes your lights to go dim, you almost certainly have a short circuit. Likely one of the fans is inoperable in a way that’s causing a high power load.
This is a job for your on-site electrician. Have him/her check the amperage that the fan circuit is consuming against the specifications of the fan. If it’s lowering the lights, there may be a bigger issue such as a circuit breaker that should be tripping, but isn’t tripping.
You may be able to isolate the faulty fan and disconnect the circuit to that fan, allowing the other fans to continue working.
I recommend manually turning that fan switch off until you get an electrician to evaluate. It could be a fire hazard.
If, by “all the lights go dim” you mean the LED lights on the relay box, I would suggest removing the output line on relay 5 and seeing if that behavior persists. If so, you may have a faulty relay. If removing the output line fixes the “lights going dim” issue, then the issue is with the circuit the relay is controlling and you would need to have your electrician involved.
But if it’s a bad relay and you have an extra relay on that box, you can move the fan circuit to that relay, re-connect the fan control card to that relay on the dry contact card.
Let us know if this is the situation, and if you need help with this.