Answer / rites

diagram is simple if u can imagine

3 phases are connected to incoming side

output 3 phases are connected to motor (motor in delta)

in each phase there are antiparallel connected thyristors.

all these thyristors firing angle is slowly changed to make
full voltage available to the output.

so what softstarter is doing applying gradually increasing
voltage up to rated to motor.

there is no control over frequency or current.

Typically take 5 to 20 seconds to ramp up.

Answer / sennapparajan

well... here we cant post such a diagram. soft starter
nothing but a starter. if will be connnected parellen with
normal DOL stater. and soft stater contacter and DLo
starter would be interlocked electricaly and mechanically.

At starting when u press the starting button the soft
starter contactoe will be closed when motor reach normal
running automativally (time setting) the S/S contactoe will
drop down and DOL starter contactor wil pick up. then motor
wil keep on running in DOL starter.

Answer / rvg.msceb

No one can give u such diagram, unless there is some commercial implications. For your kind understanding,
softstarter is nothing but a variable transformer, can be
of conventional type, or modern triac based. The
requirement is to vary the supply voltage applying to a
high capacity motor.

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