Pump Run-dry Cuttoff
I have a pump that feeds water from an underground vault. Near the bottom of the vault, there is a float valve auto-fill. The valve has failed to drop a couple of times, which has resulted in the pump running dry.
I'd like to find either a controller or a circuit I can put together that allows the pump to run from the existing timer, yet be disconnected via a relay if the flow output from the pump is low/zero. The main problem is that the pump needs to prime for 20-30 seconds in some cases, so I really need the flow switch to not trip the relay until the first 30 seconds of energized time has passed.