Branch circuit or feeder?

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Ohms law

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Sioux Falls,SD
My boss had me install a junction box next to a sub-panel in a garage and tap off that existing feeder to feed another sub-panel In a detached garage. My question is about the tap rule. My boss said that its not a feeder but technically it's a branch circuit. My concern is that my tap is a total of 80'. I read the definition of FEEDER: All circuit conductors between the service equipment and etc... And the last over current device. Hopefully this makes since and I get some clarity.
 
The key is what is that tap feeding. You said "another subpanel in a detached garage". A panel contains overcurrent devices, so this is a feeder. If most of this feeder is outside, the length may not be an issue. Hopefully, all of the other tap rules were met...

If you were just powering an outlet or hard wired device, this would be a branch circuit. But taps in branch circuits are very limited.
 
suemarkp said:
The key is what is that tap feeding. You said "another subpanel in a detached garage". A panel contains overcurrent devices, so this is a feeder. If most of this feeder is outside, the length may not be an issue. Hopefully, all of the other tap rules were met...

If you were just powering an outlet or hard wired device, this would be a branch circuit. But taps in branch circuits are very limited.
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The first sub-panel is feed from a 60 amp from main panel. The job was bid to add junction box next to sub-panel and tap with #6 ran 40' to junction box on outside of house then another 40' from that junction #4 triplex underground ran with #4 use identified for ground to sub-panel in detached garage.
 
Ohms law said:
The first sub-panel is feed from a 60 amp from main panel. The job was bid to add junction box next to sub-panel and tap with #6 ran 40' to junction box on outside of house then another 40' from that junction #4 triplex underground ran with #4 use identified for ground to sub-panel in detached garage.
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A tap conductor is typically smaller, or of lower ampacity than the conductor it taps to... such that it is not protected at its ampacity by the supply ocpd. In your case, the #4 is larger than the supplying conductor, and likely has an ampacity that is protected by the supply ocpd... which in short means its not a tap conductor.
 
Was going to say the same thing except to elaborate -- are the #4 and #6 copper or aluminum? What is the wiring type of the #6 (NM cable, THWN in raceway, ...)? If the #6 is copper, and even if Romex or UF cable, you most likely just have a split, not a tap. As Smart$ said, a tap is when you have a conductor whose ampacity is smaller than that of the overcurrent device protecting it. This requires extra protection and rules since the overload protection is at the end of the circuit and not the beginning. Now if you were running #10 copper from your 60A existing feeder and terminating in a panel with a 30A main breaker, you'd have a tap.

Note that new feeders require 4 conductors if you're under 2008 or later code, so your triplex by itself may be an issue. You need to have a separate equipment ground and can no longer use a combination neutral/ground on any feeder.
 
If the "tapped" conductors still have overcurrent protection that doesn't exceed the conductor's ampacity you just have an extension to a feeder. There is nothing prohibiting splicing and branching out feeders. Feeder tap rules only come into play with a conductor that has supply side overcurrent protection that exceeds the conductor's ampacity.
 
suemarkp said:
Was going to say the same thing except to elaborate -- are the #4 and #6 copper or aluminum? What is the wiring type of the #6 (NM cable, THWN in raceway, ...)? If the #6 is copper, and even if Romex or UF cable, you most likely just have a split, not a tap. As Smart$ said, a tap is when you have a conductor whose ampacity is smaller than that of the overcurrent device protecting it. This requires extra protection and rules since the overload protection is at the end of the circuit and not the beginning. Now if you were running #10 copper from your 60A existing feeder and terminating in a panel with a 30A main breaker, you'd have a tap.

Note that new feeders require 4 conductors if you're under 2008 or later code, so your triplex by itself may be an issue. You need to have a separate equipment ground and can no longer use a combination neutral/ground on any feeder.
Click to expand...

I did run a separate USE #4 and taped it green at both ends for my ground. I do know that you need a 4- wire system. Thanks for clarifying guys! It as clear as mud. Conclusion... I was wrong. It just didn't make sense, I i was having trouble understanding what I was reading.
 
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