why field resistance is higher than armature resistance in
dc machines? and why filed resistance is kept at min value
at starting in same time of armature resistance at max value?
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Answer Posted / binod
field resistance always more than the armature resistance
of a d.c machine(shunt or series or compound).magnetic flux
created by field.to vary generate e.m.f the field
resistance vary from min to max with increase/decrease of
speed.in motor case the speed can be vary by varrying the
field resistance(addition or substraction) with the
required torque.
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