Soft Starter Air Compressor：A soft starter is actually a motor control device with motor soft start, soft stop, light load energy saving and multiple protection functions. It is mainly a three-phase parallel thyristor and its electronic control circuit connected in series between the power supply and the controlled motor. By controlling the conduction angle of the three-phase parallel thyristor, the input voltage of the controlled motor can be changed according to different requirements to realize various functions.

Inverter compressor：Inverter, it is mainly used in places where speed is needed. Its output not only changes the voltage but also changes the frequency; the soft starter is actually a voltage regulator. When the motor is started, the output only changes the voltage without changing the frequency. The inverter manufacturers emphasize that the inverter has all the soft starter functions, but its price is more expensive than the soft starter, and the structure is more complicated. The soft starter is used where the voltage is reduced to start and stop. At this time, the motor speed does not change; but the inverter is mainly used for speed regulation, where the speed is constant, and the speed is determined by the frequency. The inverter manufacturer believes that the biggest difference between the two is that the inverter can set the operating frequency arbitrarily, but the soft starter only plays the role of soft start and stop.

Main functions of soft start

Overload protection function: The soft starter introduces a current control loop, so it can track and detect changes in the motor current at any time. By increasing

With the setting of overload current and inverse time control mode, the overload protection function is realized. When the motor is overloaded, the thyristor is turned off and an alarm is issued.

Warning signal.

Phase loss protection function: When working, the soft starter detects the changes of the three-phase line current at any time, and once the current is cut off, the phase loss can be detected

Protection response.

Overheat protection function: detect the temperature of the thyristor radiator through the internal thermal relay of the soft starter, once the radiator temperature exceeds the allowable

After the allowable value is reached, the thyristor is automatically turned off and an alarm signal is issued.

Measuring circuit parameter function: When the motor is working, the detector in the soft starter has been monitoring the running state of the motor, and will monitor

The measured parameters are sent to the CPU for processing, and the CPU analyzes, stores, and displays the monitored parameters. Therefore, the motor soft starter also has

It has the function of measuring loop parameters.

Other functions: through the combination of electronic circuits, other interlocking protections can also be realized in the system.