what is the effect when the shunt field winding is opened
in dc shunt motor (i) at the time of starting ? (ii) in
running condition ?
Answers were Sorted based on User's Feedback
Answer / p.raju
Starting condition
when the field wdg is open means there is no production of
magnetic field,even though the armature carries the current
(limitted by starter) there is no motoring action thats why
motor will not start.
Running condition
sudennly the field disappears thats why motor attains a
very high speed....
Is This Answer Correct ? | 24 Yes | 5 No |
AT the time of starting:
since the winding not energized, there will not be magnetic
field and at the same time armature being energized. so the
effect is ,a low resistance path being energized, so there
are chances of armature winding damage.
During running condition:
As soon as the field winding got de-energizes, the magnetic
field becomes close to zero(practically there will be some
residual magnetism), and speed of the motor will be much
higher and ultimately, the rotor will will be
damaged(mechanical parts).
Is This Answer Correct ? | 16 Yes | 6 No |
Answer / diptendu gantait
WHEN THE MOTOR FIELD OPEN THEN ARMATURE IS BURN-OUT OR
ROTOR GATE MAX SPEED AND MAY BE THROWNOUT BY THE DANGEROUS
SPEED.
Is This Answer Correct ? | 3 Yes | 4 No |
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