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ayad
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Join Date: Jul 2011
Posts: 1

Rotor Locked Current

07/21/2011 7:25 AM

what is rotor locked current and how we can calculate it?
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wareagle
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#1

Re: Rotor locked current

07/21/2011 7:44 AM

LRA is approximately 6 times the FLA. If you use the NEC 430.251(B) has a table that will give you this figure. Check here about half way down for table 430.251(B)
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kvsridhar
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#2
In reply to #1

Re: Rotor locked current

07/21/2011 8:14 AM

GA for the excellent link. Thanks.

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rakesh_semwal
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#4
In reply to #1

Re: Rotor locked current

07/21/2011 12:43 PM

That covers majority of motors but not all, there are induction motors in the low power segments specially shaded pole type, which shows locked rotor current in the range of 1.2 to 1.5 times of Full load current.

GA anyway.
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PWSlack
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#3

Re: Rotor Locked Current

07/21/2011 9:11 AM

Divide the terminal resistance into the applied voltage.

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electricalexpert65
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#5

Re: Rotor Locked Current

07/26/2011 10:56 AM

Refer to the motor data sheet.
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