NEC 240.21 Tap Rules - Do Feeder Circuits Require OCP?

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Murloc

Murloc

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Louisiana
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240.21 Location in Circuit. Overcurrent protection shall be provided in each ungrounded circuit conductor and shall be located at the point where the conductors receive their supply except as specified in 240.21(A) through (H). Conductors supplied under the provisions of 240.21(A) through (H). shall not supply another conductor except through an overcurrent protective device meeting the requirements of 240.4.

240.21(B) Feeder Taps. Conductors shall be permitted to be tapped, without overcurrent protection at the tap, to a feeder as specified in 240.21(B)(1) through (B)(5). The provisions of 240.4(B) shall not be permitted for tap conductors. (says tap does not need OCP)

NEC 2014 240.21.2 Taps Not over 7.5m (25 ft) Long

Where the length of the tap conductors does not exceed 7.5m (25 ft) and the tap conductors comply with all the following:

  • The ampacity of the tap conductors is not less than one-third of the rating of the overcurrent device protecting the feeding conductors. (feeder OCP required is implied here)
  • The tap conductors terminate in a single circuit breaker or a single set of fuses that limit the load to the ampacity of the tap conductors. This device shall be permitted to supply any number of additional overcurrent devices on its load side.
  • The tap conductors are protected from physical damage by being enclosed in an approved raceway or by other approved means.

From the code sections above. It appears to imply the following.

Feeder – no OCP

TAP – no OCP, follow tap rules

1st TAP termination, OCP required

However, I'm finding mix messages online that reference Mike Holt guidelines. Some say feeder OCP is necessary and some says feeder OCP is not.

Maybe it can confused from an OCP at the point of Tap vs an OCP for the feeder?
 
D

d0nut

Senior Member
Location
Omaha, NE
Yes, feeder circuits require overcurrent protection.

The tap rules are written because the tap conductors are too small to be protected by the feeder's overcurrent protection (otherwise they wouldn't be tap conductors, they would just be feeder conductors).
 
david luchini

david luchini

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Connecticut
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This part...
Murloc said:
240.21 Location in Circuit. Overcurrent protection shall be provided in each ungrounded circuit conductor and shall be located at the point where the conductors receive their supply except as specified in 240.21(A) through (H).
Click to expand...

as well as section 215.3, say that feeders require an OCPD.
 
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