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Is this a TAP? #100497
11/22/06 10:46 PM
11/22/06 10:46 PM
E
e57  Offline OP
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
So I have an old main panel I don't want to touch - yet? Customer is cash poor with baby due... But will be changed in near future.

Anyway, would you call this a tap?

All conductors are #2 cu THWN/THHN for the service and feeder conductors- 100A main in backfed old style CH breaker, with 3 other 20A circuits, and a 60' feeder off the lugs to another (new) sub on (E) feeder.

420.2 describes a tap as such:

Quote

Tap Conductors. As used in this article, a tap conductor is defined as a conductor, other than a service conductor, that has overcurrent protection ahead of its point of supply that exceeds the value permitted for similar conductors that are protected as described elsewhere in 240.4.


italics mine....

If the service conductors are 100A, so is the panel MCOP, and the feeder is rated for >100A, not <, how would this be a "TAP"?

Inpector wants an OCPD for the feeder alone. Calling into play the TAP rules.... If the feeder conductors were rated for 80A, I could see that....

What say you?


Mark Heller
"Well - I oughta....." -Jackie Gleason
2017 / 2014 NEC & Related Books and Study Guides
Re: Is this a TAP? #100498
11/22/06 11:19 PM
11/22/06 11:19 PM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,298
Estero,Fl,usa
Connections to the line side of the service disconnect are not taps, they are still service conductors. All service conductor rules still apply


Greg Fretwell
Re: Is this a TAP? #100499
11/22/06 11:39 PM
11/22/06 11:39 PM
E
e57  Offline OP
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
This is on the load side of the back-fed Main... The OCP for the feeder is the Main.


Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: Is this a TAP? #100500
11/23/06 11:54 AM
11/23/06 11:54 AM
D
dannynova  Offline
Member
Joined: Dec 2003
Posts: 18
new york
240.21 explains taps and i dont see where you can have this tap 60' feet long unless its outside or in a high bay building. 240.21(B)(1) is not over 10' and 240.21.(B)2 is not over 25'. if im reading your post correctly the length of your tap is no good.

Re: Is this a TAP? #100501
11/23/06 12:35 PM
11/23/06 12:35 PM
I
iwire  Offline
Moderator
Joined: Jan 2003
Posts: 4,391
North Attleboro, MA USA
It is not a tap.

A tap to the NEC is a conductor that has an overcurrent device ahead of it larger than the conductors rating.

Quote
240.2
Tap Conductors. As used in this article, a tap conductor is defined as a conductor, other than a service conductor, that has overcurrent protection ahead of its point of supply that exceeds the value permitted for similar conductors that are protected as described elsewhere in 240.4.


In this case all the conductors are rated over 100 amps and the over current protection is 100 amps.

All is safe and it is not a tap.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Re: Is this a TAP? #100502
11/23/06 01:51 PM
11/23/06 01:51 PM
D
dannynova  Offline
Member
Joined: Dec 2003
Posts: 18
new york
yes the #2's are good for 100 amp. 240.21 requires ocpd in each ungrounded circuit conductor and it shall be located at the point where the conductors receive their supply except as specified in 240.21(A)-(G) which are the tap rules. so where is the ocpd for this feeder. the service main which is 100 amp is the service disconnect and ocpd and the ocpd for this feeder? if its not a tap then it needs a ocpd, not the service main disconnect and ocpd.

Re: Is this a TAP? #100503
11/23/06 02:24 PM
11/23/06 02:24 PM
I
iwire  Offline
Moderator
Joined: Jan 2003
Posts: 4,391
North Attleboro, MA USA
Quote
so where is the ocpd for this feeder. the service main which is 100 amp is the service disconnect and ocpd and the ocpd for this feeder?


Yes, the 100 amp service disconnect / breaker is in fact a legal way of protecting the conductors.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Re: Is this a TAP? #100504
11/23/06 04:18 PM
11/23/06 04:18 PM
G
George Little  Offline
Member
Joined: Jan 2004
Posts: 1,489
Michigan USA
Bob- If we assumeing copper conductors I agree but if these are aluminum feeder conductors, we have to protect them at 90a.


George Little
Re: Is this a TAP? #100505
11/23/06 06:48 PM
11/23/06 06:48 PM
I
iwire  Offline
Moderator
Joined: Jan 2003
Posts: 4,391
North Attleboro, MA USA
George Happy T-Day. [Linked Image]

I agree with you, it happens that the Mark mentioned it was #2 cu THWN/THHN.

Bob


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Re: Is this a TAP? #100506
11/23/06 08:02 PM
11/23/06 08:02 PM
G
George Little  Offline
Member
Joined: Jan 2004
Posts: 1,489
Michigan USA
Same to you Bob and your family. And thanks, I missed the "cu" - got to get those glasses cleaned.


George Little
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