10 foot tap conductors

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JoeNorm

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Yes or No? Tap conductors 10 feet or less do NOT have to land on overcorrect protection.

It is my understanding that the answer is Yes
 
JoeNorm said:
Yes or No? Tap conductors 10 feet or less do NOT have to land on overcorrect protection.

It is my understanding that the answer is Yes
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I would agree based on the wording, that the answer is YES, a 10' tap does NOT have to land on a OCPD. However it could not be a panelboard due to 408.36. perhaps it could be something like a lighting control panel or a meter center.

IIRC, the 10' wording was changed a few cycles ago, but for some reason they seemed to dance around clearly stating that the tap must terminate on a single OCPD like they say in the 25' rule.
 
electrofelon said:
I would agree based on the wording, that the answer is YES, a 10' tap does NOT have to land on a OCPD. However it could not be a panelboard due to 408.36. perhaps it could be something like a lighting control panel or a meter center.

IIRC, the 10' wording was changed a few cycles ago, but for some reason they seemed to dance around clearly stating that the tap must terminate on a single OCPD like they say in the 25' rule.
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You can't tap a tap either so it still would limit you to very few possibilities - I can't think of any at the moment. Like you mentioned for panelboards most anything that is not already an overcurrent device would likely require certain overcurrent protection ahead of it anyway. If said item is rated for same ampacity as your feeder- you don't exactly have need for a feeder tap to begin with.
 
I was looking for information on 10 ft tap rule approved raceway . Would Mc cable of 1 ort be an approved raceway .
 
kwired said:
Probably one of those judgement calls. In general a cable is not a raceway though.
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How would MC cable be different than FMC conduit, in terms of its physical function? Only difference is factory-wired vs field-wired, yet FMC conduit would clearly count as a raceway in this context.
 
kwired said:
You can't tap a tap either so it still would limit you to very few possibilities - I can't think of any at the moment. Like you mentioned for panelboards most anything that is not already an overcurrent device would likely require certain overcurrent protection ahead of it anyway. If said item is rated for same ampacity as your feeder- you don't exactly have need for a feeder tap to begin with.
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In addition to the items I said in post #2, a switchboard is another item that has no requirement to be protected at it's rating by an OCPD
 
Carultch said:
How would MC cable be different than FMC conduit, in terms of its physical function? Only difference is factory-wired vs field-wired, yet FMC conduit would clearly count as a raceway in this context.
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If the word raceway is what is used then that excludes cables, unless there is more wording that allows otherwise.

Note I haven't double checked how this is worded. I do agree that for most part MC and FMC in reality provide about the same physical protection to what is inside, if same outer material. Steel sheath would be more protective than aluminum sheath.

Checked, it says raceway. though MC and FMC likely offer similar protection, I think you must use "raceway" to comply.

more editing: the 25 foot rules is more lenient, but at same time you have min conductor sized one third of the overcurrent protection instead of one tenth.
 
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JoeNorm said:
Back to the OP, I was thinking of a small, main lug panel. But I have not read 408.36 yet
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Panelboards must be protected at no more than their rating, didn't check but probably is what is mentioned in 408.36. Therefore you can't feed a main lug panel with a feeder tap, you would need a main breaker panel or other proper overcurrent protection ahead of the panelboard, or back fed main with proper hold down kit is equivalent to a main breaker panel.
 
Here is the wording in the 2011 code for 240.21(B)(1)(1)(b):
Not less than the rating of the device supplied by the tap conductors or not less than the rating of the overcurrent protective device at the termination of the tap conductors.
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In 2014 it was changed to:
Not less than the rating of the equipment containing an overcurrent device(s) supplied by the tap conductors or not less than the rating of the overcurrent protective device at the termination of the tap conductors.
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One commentary I just pulled off the web said:
The previous code language allowed the tap conductor ampacity to be rated no less than the “device” supplied by the tap conductors. This was misleading and opened the door to the idea that a tap conductor could be without any overcurrent protection at the load end of the conductor if it supplied a device rather than an overcurrent device.
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Not sure exactly what they seem to be trying to allow or not allow, but it seems they want "some" overcurrent device there without saying that if there are multiple OCPDs that their sum has to be not greater than the ampacity of the tap conductors (which would seem to be logical, and equivalent transformer protection in 450.3(B) where the protection consists of multiple devices).
 
So a tap conductor could not supply a meter base, then a panel with overcorrect protection directly next to it?
 
JoeNorm said:
So a tap conductor could not supply a meter base, then a panel with overcorrect protection directly next to it?
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240.21 feeder tap rules cover conductors tapped from a feeder. If what you are describing is all ahead of the service disconnecting means they don't fall under 240.21 and are not feeder taps. They are simply taps made to service conductors. There is no "tap rules" for service conductors they are all presumed to have no protection ahead of them that limits how much current can flow.

After that first overcurrent device - if the conductor is protected by the device it is a feeder. If it has ampacity less than the device (other than allowed next size up rule) it is a feeder tap and must comply with one of the feeder tap rules of 240.21.
 
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