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#210212 - 06/03/13 03:50 PM Large Feeder Tap  
cgw  Offline
Member
Joined: Jul 2004
Posts: 133
Rochester NY
Suppose I had a large feeder running across a building (3 sets 600) and I wanted to tap the feeder with 1 set #1. Just tapping one set of the large feeder is correct and practical?


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#210213 - 06/03/13 04:12 PM Re: Large Feeder Tap [Re: cgw]  
sparkyinak  Offline
Member
Joined: Jul 2007
Posts: 1,317
Alaska
Without all the technical info of what you hooking up and what the existing load,If it meets the tap requirements of article 240 and not overload the original load, and meets other applicable requirements, I don't see a problem


"Live Awesome!" - Kevin Carosa

#210215 - 06/03/13 06:50 PM Re: Large Feeder Tap [Re: cgw]  
gfretwell  Offline


Member
Joined: Jul 2004
Posts: 9,069
Estero,Fl,usa
I have a problem with it. The whole idea of paralleled conductors is that you are going to balance the load across the conductors equally (same size, length etc)
If you unequally load one conductor, you are defeating the O/C protection.
The only way I see this as legal is if you group them, make your tap and then break them out again.

I will look for a code reference


Greg Fretwell

#210216 - 06/03/13 07:00 PM Re: Large Feeder Tap [Re: cgw]  
gfretwell  Offline


Member
Joined: Jul 2004
Posts: 9,069
Estero,Fl,usa
This is the commentary from the handbook

Quote
Where individual conductors are tapped from conductors in parallel, the tap connection must include all the conductors in parallel for that particular phase. Tapping into only one of the parallel conductor would result in unbalanced distribution of tap load current between parallel conductors, resulting in one of the conductors carrying more than its share of the load, which could cause overheating and conductor insulation failure. For example, if a 250-kcmil conductor is tapped from a set of two 500-kcmil conductors in parallel, the splicing device must include both 500-kcmil conductors and the single 250-kcmil tap conductor.


Greg Fretwell

#210220 - 06/03/13 08:51 PM Re: Large Feeder Tap [Re: cgw]  
sparkyinak  Offline
Member
Joined: Jul 2007
Posts: 1,317
Alaska
I stand corrected! I missed it was a parallel run of 600's. Excuse me why I sit here looking stupid and eat my crow sandwich...


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#210221 - 06/03/13 09:46 PM Re: Large Feeder Tap [Re: cgw]  
gfretwell  Offline


Member
Joined: Jul 2004
Posts: 9,069
Estero,Fl,usa
It is not insurmountable, you just need a big, 7 hole, Polaris connector.


Greg Fretwell

#210222 - 06/04/13 12:54 AM Re: Large Feeder Tap [Re: cgw]  
sparkyinak  Offline
Member
Joined: Jul 2007
Posts: 1,317
Alaska
Split bolts mastic pads and Super 88 will do the trick....
anyone

Lol!


"Live Awesome!" - Kevin Carosa

#210225 - 06/04/13 09:52 AM Re: Large Feeder Tap [Re: gfretwell]  
cgw  Offline
Member
Joined: Jul 2004
Posts: 133
Rochester NY
Originally Posted by gfretwell
It is not insurmountable, you just need a big, 7 hole, Polaris connector.


If the feeder is for a transformer, would it be easier to connect (the tap) to the transformer primary connections.



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