HV Frequecy Sensitive Starting Cabinet-RQVP

1. The high-voltage motor frequency-sensitive starting cabinet consists of an operating cabinet and a frequency-sensitive rheostat cabinet, and it has a cabinet-type protective structure. 

The frequency-sensitive rheostat cabinet is composed of frequency-sensitive rheostats, automatic switches, AC contactors, time relays and other components. 

The front and rear doors of the operating cabinet are opened and consist of knife switches, circuit breakers, transformers, and power transformers.

 The front door is equipped with ammeters, signal lights and control buttons, etc. The time relay is adjustable, and the starting time can be freely adjusted.

 Frequency-sensitive rheostats are generally equipped with adjustable taps to adapt to the starting of motors under various different conditions.

It has short-circuit and overload protection for the motor. By taking advantage of the characteristic that the impedance of the frequency-sensitive rheostat decreases as the motor speed increases, the impedance is large during starting to achieve the effect of limiting the starting current.

2. The starting cabinet composed of frequency-sensitive rheostats and other control electrical appliances.

 It is mainly used for starting large and medium-capacity AC wound rotor induction motors. Since the impedance of the frequency-sensitive rheostat changes smoothly and automatically with the speed of the motor, the starting process is stable without the impact of starting current and starting torque, and the control circuit is also simple. 

In the frequency-sensitive starting cabinet, the frequency-sensitive rheostat is in the circuit of the motor rotor winding. When the contactor is connected to the power supply, the motor starts to start.

 Since the rotational speed of the motor rotor during starting gradually increases from zero, and the impedance of the frequency-sensitive rheostat gradually decreases from a relatively large value, the starting current is initially limited to a smaller value and gradually increases. 

As the motor starting process ends, the rotational speed of its rotor increases to the rated value. 

At this time, the impedance of the frequency-sensitive rheostat has automatically decreased to a very small value for the normal operation of the motor, and the frequency-sensitive rheostat cabinet automatically shorts the frequency-sensitive rheostat.