NEC 2005 - NEC 2011 FIRE PUMP OCPD

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AAEB

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Southeast Asia
Guys good day!,


Just want to ask the difference between NEC 2011 695.4(b)(2)(a)"the overcurrent protective device(s) shall be RATED to carry indefinitely the sum of the locked-rotor current of the fire pump motor(s)..... against NEC 2005 695.4(b)(1) "the overcurrent protective device(s) shall be selected or set to carry indefinitely the sum of the locked-rotor current of the fire pump motor(s)..... Does this two articles have same meaning?
The way i understand this is "shall be selected or set" is that you can size the OCPB using art. 430.250 (FLA x 1.25%) but setting the long-time delay to withstand the LRC, while " shall be rated" is that you have to size the OCPD based on the LRC plus Jockey pumps and controllers. am i wrong with this?

please enlighten me..:angel:

thanks in advance

AAEB
 
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