residential feeder taps

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JoeNorm

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Lets say I have a meter main feeding a residence with 200 amps. Feeders come into a basement and the pipe is accessible. What rules apply to being able to tap a small panel off of these 200 amp feeders. Is this the 10 and 25 foot tap rules?

If I tap off the feeders is it a requirement that the tap wires land on a breaker? Can I not land on a main lug panel with one or two circuits?
 
The particulars in making the tap seem bewildering but in answer to your question, the 240.21 tap rules would apply.
I would suggest looking at that Section as there are various requirements.
 
The 10' and 25' tap rules are based on among other things the size of the tap conductors. That's where the 10% and 1/3 rules come into play. Yes as EF stated you need to terminate in a single OCPD.
 
I have read the tap rules. I get a little confused as to the difference of whether you're tapping off of a feeder or a service entrance conductor. Is there a difference? Or is it that if you are tapping off a service entrance conductor you are just creating another service entrance conductor and are abiding by separate rules altogether?

In regards to always landing on a breaker. It appears that is only for the 25' tap rule(please, correct me if I am wrong). I do not see that requirement in the 10' tap rule.

thanks
 
Yes, I am interested in feeder taps here. Just clearing up that there is in fact different rules for service entrance. Thanks
 
JoeNorm said:
In regards to always landing on a breaker. It appears that is only for the 25' tap rule(please, correct me if I am wrong). I do not see that requirement in the 10' tap rule.
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It's not in Article 240 it's in Article 408.
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.
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infinity said:
It's not in Article 240 it's in Article 408.
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Yeah thats a little convoluted. Say I have a 200A feeder, a 100A feeder tap landing on a 100A MLO panel. 240.21(B)(1) seems to be satisfied, but not 408.36. Say I change the panel to a 200A MLO, now 408.36 is satisfied, but I need to increase the tap conductors to the "rating of he equipment" or 200A, but then I dont have a tap anymore.

I am not sure what the reasoning is for not specifically requiring the tap to terminated on a single OCPD in the 10 footer. Apparently that want us to be able to feed certain equipment with taps. Switchboards to not have the protection requirement, so that is an example.
 
A classic example of "the more you learn about the Code, the less you know" :)
 
I am reading the 2020 code, which might explain it.

Mine says Individual protection shall not be required for a panelboard protected by two main circuit breakers or two sets of fuses in other than service equipment, having combined rating not greater than that of the panel board.............

"in other than service equip" is revised for 2020.
 
JoeNorm said:
I am reading the 2020 code, which might explain it.

Mine says Individual protection shall not be required for a panelboard protected by two main circuit breakers or two sets of fuses in other than service equipment, having combined rating not greater than that of the panel board.............

"in other than service equip" is revised for 2020.
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Oh of course. MLO service panelboards were removed from the 2020 so I am guessing exception #1 basically was deleted, and what used to be exception 2 in the 2014 is now exception 1. IMO that is one of the worst code changes and I guess I struck it from my memory in hopes it would go away.

I honestly dont even understand what that exception is saying.
 
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