Soft starter starts modes

Gozuk soft starter has six starting modes for the client to select according to the motor and loads (also see stop modes):

Soft starter current-limit start



The diagram shows the waveform of motor current. I1 is the starting limit-current preset value. When starting, the output voltage rises quickly till the motor current up to I1 value and not beyond this value. The motor runs steadily in pace with the rising of output voltage, and when the motor runs to be the rated speed, the output current will have a quick-drop and down to the motor rated current (Ie value),then the bypass contactor is working, the stating process is finished.
Note: When motor load is too light or I1 preset value is too high, the max current of starting may can not reach I1 value. This starting mode fits for the conditions which requires strict current limitation of starting.

Soft starter voltage ramp start



The diagram shows the output voltage waveform. In the diagram, the U1 is the initial voltage value of starting. When starting, if the motor current is not more 400% than the rated current, the output voltage of soft starter will rapidly rise to U1, and the output voltage rises gradually to the rated voltage (Ue), and the motor gradually increase and until running at rated voltage and speed, and then the bypass contactor closed, the starting process finished.
Note: "T" is the automatic detecting starting time according to load. It will be less than set time when the loads are light; this starting mode fits for the common occasions where the motor need to be started smoothly.

Torque control + current limit or voltage ramp



The diagram shows the output changing waveform of torque control starting mode. When the static friction force of heavy load is too stronger to start the motor, user can use this starting mode. At first state of starting, the motor needs a higher voltage to conquer the static friction force of heavy load, and then starts with current-limit or voltage ramp mode to start the heavy motor.
Note: This mode will cause big-current shock to the motor, so if the voltage ramp or current limit starting mode can startup the motor, it is better not to use this torque control mode to start.

Soft starter current ramp start



The diagram shows the output current waveform. In the diagram I1 is current value preset by P6 code, and T1 is time value present by P1 code. This starting mode has very stronger speed-up ability and is suit for the bipolar motors, and it can reduce the starting time.

Double closed loop
This starting mode uses voltage ramp and current limit double closed loop circuit; it is a composite starting mode. The output voltage waveform is changed as the difference of motor and loads. This mode fits for smooth starting and strictly current limit occasions.