In the water supply system, in order to avoid the direct start of the pump caused by the starting current is too large, the technical staff will generally install the pump inverter or soft starter. Then the pump inverter with the soft starter in the end what is the difference? Xiaobian below for your doubts.
Soft starter is a set of soft start, soft stop and multi-function protection in one of the motor control equipment. It can achieve the entire start-up process without impact and smooth start the motor. The soft starter solves the problem of the impact of the motor starting on the grid, and it also has a variety of motor protection functions.
Soft starter protection
1. Overload protection: soft starter introduced a current control loop, which at any time to track the detection of motor current changes. By increasing the overload current setting and inverse time control mode, the overload protection function is realized. When the motor is overloaded, turn off the thyristor and send an alarm signal.
2. Phase protection: During the operation, the soft starter monitors the change of the three-phase current at any time. When a certain phase current is zero, the soft-phase protection is made immediately.
3. Overheat protection: through the soft starter internal thermal relay to detect the temperature of the thyristor radiator, once the radiator temperature exceeds the allowable value automatically turn off the thyristor, and send an alarm signal.
Pump frequency converter
Pump inverter is a dedicated inverter, that is, on the basis of the general frequency converter to increase the dedicated water supply function. Pump frequency converter is to change the motor operating frequency of the way to control the motor power control equipment. The pump frequency converter will adjust the voltage and frequency of the output power supply according to the breaking of the internal IGBT, according to the actual needs of the motor to provide the required power supply voltage, and thus achieve the purpose of energy saving and speed control.
Pump frequency converter function
Pump inverter in addition to overload, lack of phase, overheating and other protection functions, but also has the following dedicated water supply protection.
1. Water protection: When the pressure of the pipeline is less than the set value of the water protection fault detection threshold, after the delay, the pump inverter will alarm, the pump stops working, to avoid the pump dry pumping problem.
2. Sensor feedback disconnection protection: When the pressure sensor fails, the pump frequency converter detects the voltage is less than the feedback disconnection detection value, the feedback disconnection detection time, the pump frequency converter will alarm, the pump stops working, thus ensuring the The stability of constant pressure water supply system.
3. High and low water pressure protection: water pump inverter can be set to high water pressure or low water pressure protection, when the pipe pressure is greater than the high water pressure set value or less than the low water pressure set value, the pump inverter will alarm and then stop jobs.