Feeder Overcurrent Protection - Max?

[designer82]

Section 215.3 says that OCPD shall be not less than non-continuous + 125% of continuous.

Is there a maximum size limit on feeder OCPD?
Didn't see it anywhere so I'd like to check.

Thanks

 

[infinity]

I believe that you're only limited by the largest OCPD that you can use.

 

[tortuga]

Section 215.3 says that OCPD shall be not less than non-continuous + 125% of continuous.

Is there a maximum size limit on feeder OCPD?
Didn't see it anywhere so I'd like to check.

Thanks

Thats not what is says, it says minimum conductor ampacity.
240 deals with overcurrent protection, 310 has your tables

 

[david luchini]

Section 215.3 says that OCPD shall be not less than non-continuous + 125% of continuous.

Thats not what is says, it says minimum conductor ampacity.

Section 215.3 is titled Overcurrent Protection. It doesn't say anything about conductor ampacity.

 

[don_resqcapt19]

Section 215.3 says that OCPD shall be not less than non-continuous + 125% of continuous.

Is there a maximum size limit on feeder OCPD?
Didn't see it anywhere so I'd like to check.

Thanks

Just remember that, in general, the ampacity of the conductor must match the rating of the OCPD. If you install a higher rated OCPD, then you must also install a larger conductor.

 

[tortuga]

Section 215.3 is titled Overcurrent Protection. It doesn't say anything about conductor ampacity.

my bad i was looking at 215.2

 

[designer82]

Just remember that, in general, the ampacity of the conductor must match the rating of the OCPD. If you install a higher rated OCPD, then you must also install a larger conductor.

When I install a conductor to match the rating of the OCPD (or higher), are we referring to the base or derated ampacity of the conductor?

 

[don_resqcapt19]

When I install a conductor to match the rating of the OCPD (or higher), are we referring to the base or derated ampacity of the conductor?

The conductor must be protected at or below its ampacity under the conditions of use. That means you apply any required ampacity adjustment and corrections to determine the actual ampacity.