Common Problems And Solutions Of Water Pump Control Cabinet

Common problems and solutions of water pump control cabinet


1. Reverse liquid level control

Phenomenon: when the water supply (drainage) tank is full (without water), the control cabinet will start to work, but without water (the water collecting tank is full), the control cabinet will stop and use in the opposite way.

Solution: according to the instructions of float switch, that is, the water supply is normally closed, the drainage is normally open, and the float line is connected again.


2. The starter motor wire is wrongly connected when 2 star delta is decompressed

Phenomenon: when the motor starts, it is normal, but when it turns to operation, the motor suddenly stops or the air switch is disconnected.


1) Turn to stop the motor in operation, check whether the wiring from the motor end to the terminal of the control cabinet conforms to the electric circuit diagram according to the wiring diagram, and readjust the wiring after checking.

2) When turning to operation, the air switch is disconnected, and check whether the connecting copper strip on the motor terminal is completely removed or whether the connecting cable is broken in the middle.

3. Insufficient starting torque of auto coupling decompression

Phenomenon: the starting torque of the motor is not enough when the auto coupling decompression starter is started.


1) Check for phase loss.

2) For heavy load starting, change 65% tap of autotransformer to 80% tap. (the following one-in-service and one standby direct start cabinet is used in general, so it is unable to fail over.


4. Direct starting cabinet with one in use and one standby under 15kw can not be switched over 

Phenomenon: during the test of fault switching, a wire of the main control AC contactor coil of the main water pump shall be removed at will, instead of automatically switching to the standby pump.

Solution:because the fault signal of the following one in service one standby control cabinet adopts the normally open contact of thermal relay as the fault signal. When the solid test fails to switch over, the lack of the hot relay "97" and "98" will cause one person to fail.