Is it possible that motor will be over than kW rating when operated ?
Is it possible that motor will be over than kW rating when operated ?
(OP)
Dear any guru
Is it possible that motor will have power over than kW (From name plate) rating when operated ?
Young Eng
Is it possible that motor will have power over than kW (From name plate) rating when operated ?
Young Eng






RE: Is it possible that motor will be over than kW rating when operated ?
RE: Is it possible that motor will be over than kW rating when operated ?
Rafiq Bulsara
http://www.srengineersct.com
RE: Is it possible that motor will be over than kW rating when operated ?
One is to run it at a lower temperature than rated ambience, which usually is around 40 C.
The other method is to apply a higher than rated frequency.
Motor ratings are actually torque based and upping frequency and speed makes the motor deliver more HP or kW, if you prefer that, than at nominal speed.
It is being done all the time. Very common is to get 73 % more out of a motor by running the nominal 50 Hz motor at 86.5 Hz. Also, a 50 Hz motor will deliver 20 % more power when run from a 60 Hz grid. Provided, of course, that voltage/Hz is kept at nominalvalue.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Is it possible that motor will be over than kW rating when operated ?
Is there a technical reason to choose 86.5 Hz?
Thanks
Yours
Bill
Bill
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"Why not the best?"
Jimmy Carter
RE: Is it possible that motor will be over than kW rating when operated ?
Muthu
www.edison.co.in
RE: Is it possible that motor will be over than kW rating when operated ?
Requires motor to be a six-lead one. Connect a 400 V wye 50 Hz motor in delta (230 V @ 50 Hz) and run it at 400 V @ 86.5 Hz
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Is it possible that motor will be over than kW rating when operated ?
Yours
Bill
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Is it possible that motor will be over than kW rating when operated ?
A 230 V, 50 Hz (delta or wye connected) can be run at 415 V, 86.5 Hz directly without any winding reconnection, right ?
Muthu
www.edison.co.in
RE: Is it possible that motor will be over than kW rating when operated ?
The way the V/Hz ratio at the motor is maintained is to reconnect a 415V motor for 240V (415V/1.73=240V, wye to delta connection change). Now the motor that is connected for 240v 50Hz may be energized at 415V at 86.5 Hz.
Gunnar just taught me that.
Thanks again Gunnar.
Bill
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"Why not the best?"
Jimmy Carter
RE: Is it possible that motor will be over than kW rating when operated ?
A 415 Wye/230 V Delta is a dual voltage motor for the same rating.
My question was if a 230 V, 50 Hz motor (delta or wye) can be run at 415 V, 86.5 V without doing anything to the connection. And the answer is, yes.
Muthu
www.edison.co.in
RE: Is it possible that motor will be over than kW rating when operated ?
A 240V motor will have the same V/Hz ratio at 415V 86.5 Hz.
Therein lies my confusion.
Bill
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"Why not the best?"
Jimmy Carter
RE: Is it possible that motor will be over than kW rating when operated ?
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Is it possible that motor will be over than kW rating when operated ?
Whew! I'm glad we cleared this up...
Keith Cress
kcress - http://www.flaminsystems.com
RE: Is it possible that motor will be over than kW rating when operated ?
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...