https://www.solarpumpfactory.net/product/sewage-pump/wqqw-submersible-sewage-pump/
he stator of the high- power sewage pump is embedded with a thermal control switch. Normal temperature is "normally closed" state, when the stator temperature reaches 125C, the switch opens. A water leakage probe is installed in the oil chamber for water leakage detection. The signal line of the oil and water intake probe is connected.Connect any line to the leakage circuit breaker; when the mechanical seal on the pump side leaks and the oil- -water ratio in the oil chamber reaches a certain concentration, the oil-water probe will send an alarm signal and the power supply is cut off and the pump stops working automatically.