Regarding the situation where the operation signal remains active after the on-site equipment is shut down
Thread Content
Problems that occurred during production in our factory: 1. After the electrostatic precipitator was shut down, operating signals were still detected in the cabinet area, and the relays remained lit; the issue was resolved after replugging them (the circuit was disconnected). The relays together with their mounts had been replaced before, but that did not solve the problem fundamentally. Additionally, similar issues have occurred with individual pumps as well; the operation signal remained active even after the pump stopped, but it worked properly after the connection was re-established. I hope all the experienced sailors here can analyze this for me! :P
What brand of relay is being used? Also, after the pump stops operating, was the voltage of the relay coil on the instrumentation side measured?
There must be some interference electricity; check whether the shielding layer is properly grounded.
Since the problem persists even after replacing the relay, it indicates that there is signal interference
Replace it with a 220V relay; it’s likely that the interference voltage isn’t strong enough to drive it
There is a high likelihood of electrostatic discharge; I have measured it before, and the induced voltage in some domestically produced MCC rooms can reach 100V
Replace it with a 220V relay, and check whether the shielding of the signal wires is properly connected; an induced voltage is commonly present in the signals indicating the operation of the pump.