7. Test Run and Application
EM-GS User's Manual
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and is suit for the bipolar motors, and it can reduce the starting time.
Diagram 7.5
7.2.5
Voltage current-limiting double closed-loop start
(Both voltage ramp and current limit) to start (The
F9
items set as"5"). 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
different motor and the load equipments. This mode fits for smooth starting and strictly current limit occasions.
7.3 The stopping mode and application
The soft starter has two stopping modes; those are Soft-stopping mode and Free-stopping mode.
7.3.1 Soft-stopping Mode
(The
F2
item is not set as"0") When using this mode to stop the motor, the power supply of motor will be transferred
from the bypass contactor to the controlled silicon of soft starter, and the output voltage of starter will be reduced
gradually so that the running speed of motor can be cut down smoothly avoid mechanical shock. The output ending
voltage is the same as the starting initial voltage. Soft-stopping mode can reduce or remove the surge of the loading
equipments such as the water pump.
You can set the soft-stopping current limit value through the
FF
code to reduce the high current shock to the motor
when stopping. This current limit value is percentage of
F5
.
7.3.2 Free-stopping Mode
(The
F2
code is set as"0") When using this mode to stop the motor, the soft starter will cut off the connection to the
bypass contactor and forbid the controlled silicon output voltage after receiving stopping command. The motor
stops gradually with its inertia. One soft start connecting with two motors must use this free stopping mode.
Generally, if the soft stopping mode is not necessary, please choose the free stopping mode to prolong the service
life of soft starter. This mode completely forbids the instantaneous output; avoid instantaneous high current shock to
the motor of specially applying.
7.4Special application
In parallel the starting of the motors:
If the motors total power is less than 80% of soft starter, the motors
can be parallel connection. But at this time should be also provides for each motor thermal protection device.
Double speed motor:
Motor soft starter can cooperate with double speed motor starting, must go through
demagnetization delay period before change from low speed to high speed, to avoid anti-phase current generated
between the lines and motor.
Too long cable:
f the cable is too long, the cable voltage drop will be high, and that will increase current loss
and reduce starting torque, so please use big KW soft starter and motor.
