Answer Posted / vinod

it one kind of control method in the vfd.
for example the the unwinder and rewinder has a opposite
torque directions.
in unwinder the speed and torque will be in opposite
direction
in rewinder the speed and torque will be in same direction.
so,an effective toruqr control can be made with a vvfd.

what is vA rating and class of a ct.

1807

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hello friends.. I have a doubt regarding the operation of dc machines.. I studied in a text book that a dc machine can be used as a generator and as a motor.. is this possible? If so,please send me the info about this topic.. you can also send your info to my mail.

1976

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Why current shoots up in the secondary on the knee point voltage during saturation test of CT? How core saturation effects the secondary current (while the primary side is open)? What the logic behind this?

1952

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11kv/433v delta/star distribution transformer primary side full load Ht current is 83.33A in , but input side VCB rating 800A.why?

1609

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advantages and disadvantages of inverse definite minimum time RELAY

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How to identify the start and end of 3phase 12 lead motor if U1, U2, etc numberings are lost or erased.

2090

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Why does inductive loads consume KVARs?

2008

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Can double compression glands be used with regular cables?

2045

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How can we calculate the transformer rating if the load calculated is 1000KW (11Kv Supply)?

1004

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Why ground terminal is used in pot meter 10k ohms

1819

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what is the standard duration after failure EB power

1775

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How to calculate multiplying factor of dc energy meter

1605

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How do you compute voltage drop and cable size over distance?

2201

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please give me all the Alarm .Trip ,Safety Relays & Conditions of UPS Systems mail me on ashokbabunhce@gmail.com

1731

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in dc suppy frequency is zero why? if dc frequency is zero how to exist dc transients and ac transients

2033

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