Soft starter cabinets are primarily used for starting high-power motors of various types, replacing traditional starting methods with soft starting to achieve smooth startup, reduce starting current, minimize the mechanical impact of high current on the motor during startup, and reduce the impact on the power grid, thereby improving power quality and saving energy. By utilizing stall protection and quick protection, they prevent motor overheating and burnout caused by mechanical faults or stalling blockages, reduce voltage drops due to high current that could affect other electrical appliances, decrease wear and tear, extend the motor's service life, and save on mechanical maintenance costs.

Soft starter control cabinets are mainly used to receive high and low water level control signals from level controllers, controlling the automatic start and stop of liquid pump motors. Their control methods include full-voltage starting, reduced-voltage starting, soft starting, and frequency conversion control.

In the control circuit of this series of control cabinets (boxes), both automatic control and manual control are provided, along with overcurrent, overvoltage, undervoltage, phase loss protection, and fault alarm functions. Before using this product, it is necessary to verify the wiring according to the electrical schematic diagram, adjust the settings of the corresponding components according to the actual requirements of the motor, and then start.

1. Automatic operation: Turn on the power, the power indicator light will illuminate. Turn the selector switch to the "automatic" position and check whether the motor controlled by the control cabinet (box) operates according to the instructions of the level controller. When the liquid level reaches the control level, the corresponding level indicator light will illuminate, the normally open contacts of the corresponding limit control relay will automatically close, the secondary control circuit will automatically connect, the motor will start, and the run indicator light will illuminate simultaneously. When the water level reaches the stop level, the corresponding indicator light will illuminate, the normally closed contacts of the corresponding limit control relay of the level measurement and control instrument will open, the secondary control circuit will break, the motor will stop working, and the run indicator light will turn off.

2. Manual operation: Turn on the power, the power indicator light will illuminate. Turn the selector switch to the "manual" position, press the start button, the motor will begin to run, and the run indicator light will illuminate. Press the "stop" button, the motor will stop running, and its run indicator light will turn off.

3. Regardless of the control method used, when the extreme water level is reached, its over-limit water level signal contacts will connect, causing the secondary control circuit to lose power, stopping the motor, and triggering an audible and visual alarm signal. If a fault occurs during motor operation, the fault indicator light will illuminate, and the electric bell will automatically sound an alarm. At this point, press the stop button to force the motor to stop working.