10 ft. tap question

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augie47 said:
My opinion is that the 10 ft tap rule is one (maybe the only one) that does not specifically state terminate in a single overcurrent device.
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The rule for the OCPD comes in at the begining of 240.21.

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).

Rick
 
benaround said:
What does 240.21(B)(1)(1)(b) mean?
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The "OR" makes a difference:

b. Not less than the rating of the device supplied by the tap conductors

NEC Def:
Device. A unit of an electrical system that carries or controls electric energy as its principal function.

Is a panel a device ?????

OR
not less than the rating of the overcurrent protective device at the termination of the tap conductors.

It is important to note (a) also: (1) The ampacity of the tap conductors is
a. Not less than the combined calculated loads on the circuits supplied by the tap conductors, and
 
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I agree you need OCPD on the supply side or on the panelboard your taps land on.

In fact at the end of 240.21(B)(1) it reminds you in a FPN to see 408.36 which tells you your panelboard needs protection.
 
augie47 said:
My opinion is that the 10 ft tap rule is one (maybe the only one) that does not specifically state terminate in a single overcurrent device.
It states (a) terminate in a "device" and if you look up "device" in Art 100 it seems to cover panelboards; and (B) the calculated load must not exceed the ampacity.
I don't like it, but from reading, I'd say the Code would allow you to terminate in a MLO panel if your calculated load allowed.
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Sorry to post three times in a row but I disagree augie. This tap rules does not seem to allow you to violate

408.36 Overcurrent Protection.​
​
​
In addition to the requirement
of 408.30, a panelboard shall be protected by an
overcurrent protective device having a rating not greater
than that of the panelboard. This overcurrent protective device
shall be located within or at any point on the supply​

side of the panelboard.
 
I appreciate that and I'm sure benaround does also.
In previous discussions that has not been mentioned. \Kudos to you.
Now if I can remember it ! :D
 
There was a change in the rules that require overcurrent protection for panels between the 2005 and 2008 codes. Under the 2005 code, if the panel was a power panel, the 10' tap rule could be used without a main breaker in the panel as long as the ampacity of the tap conductors was equal to or greater than the panel rating.
 
augie47 said:
I appreciate that and I'm sure benaround does also.
In previous discussions that has not been mentioned. \Kudos to you.
Now if I can remember it ! :D
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Augie is actually correct in how he stated that 240.21(B)(1) does not require an OCPD at the load side of the tap conductor.

408.36 will be the determining factor, requiring the OCPD at the panel.

Technicalities-details... ;)

don_resqcapt19 said:
There was a change in the rules that require overcurrent protection for panels between the 2005 and 2008 codes. Under the 2005 code, if the panel was a power panel, the 10' tap rule could be used without a main breaker in the panel as long as the ampacity of the tap conductors was equal to or greater than the panel rating.
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I have not read that portion of the '08 yet...soon I will as we may be going to the '08 sometime soon in 2011. :mad:
 
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