single motor conductor 125% and ocpd up to 250% conductors #14,!2,!0.

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cocodrilo

Member
I recently installed a 30 amp ocpd on a #12 thhn to feed a 2 hp 230 volt 1ph pool pump.
table 430.248 FLA is 12 amps , size of wire at 125 % = 15 amps I used # 12awg then I sized the ocpd -
at 250% x 12 = 30 amp breaker this motror has intregal overload protection.

the inspector told me I cannot have a #12 awg conductor on a 30 amp breaker and I know he is referring to table 240.4 where these sizes are not allowed to be protected over those ratings. i.e. 14awg-15amps, 12awg-20amps, 10awg-30amps.

However I thought the motor rules allowed this to be praticed?
 

jumper

Senior Member
I recently installed a 30 amp ocpd on a #12 thhn to feed a 2 hp 230 volt 1ph pool pump.
table 430.248 FLA is 12 amps , size of wire at 125 % = 15 amps I used # 12awg then I sized the ocpd -
at 250% x 12 = 30 amp breaker this motror has intregal overload protection.

the inspector told me I cannot have a #12 awg conductor on a 30 amp breaker and I know he is referring to table 240.4 where these sizes are not allowed to be protected over those ratings. i.e. 14awg-15amps, 12awg-20amps, 10awg-30amps.

However I thought the motor rules allowed this to be praticed?

Tell inspector to reread 240.4(D) and(G).
 

cocodrilo

Member
motor rules

motor rules

Tthanks for re-affirming what I thought was the correct code rule I had learned from one of Mike Holts classes here in Florida. I guess the inspector can use some continuing Ed.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
To the Op are you doing this to avoid GFCI protection. If you are I think you are making a mistake and in 2011 you will need gfci protection in either case.
 

electures

Member
Location
South Jersey
I recently installed a 30 amp ocpd on a #12 thhn to feed a 2 hp 230 volt 1ph pool pump.
table 430.248 FLA is 12 amps , size of wire at 125 % = 15 amps I used # 12awg then I sized the ocpd -
at 250% x 12 = 30 amp breaker this motror has intregal overload protection.

the inspector told me I cannot have a #12 awg conductor on a 30 amp breaker and I know he is referring to table 240.4 where these sizes are not allowed to be protected over those ratings. i.e. 14awg-15amps, 12awg-20amps, 10awg-30amps.

However I thought the motor rules allowed this to be praticed?

#14 is also acceptable.
 
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