Tap Question

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Alwayslearningelec

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I have this existing feeder being extended to new panels. There is an existing tap box.
Does this tap have to be within a certain distance of the panel its feeding per code?
Thanks.
 

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Look at the definition of a tap (240..2)
In the "existing" you had conductors with an ampacity less than the feeder.
In the new you are just extending the same size feeder (same ampacity)
 
augie47 said:
Look at the definition of a tap (240..2)
In the "existing" you had conductors with an ampacity less than the feeder.
In the new you are just extending the same size feeder (same ampacity)
Click to expand...
The existing has #2/0 being "tapped" off #350 riser. Is that a tap?
 
infinity said:
According to you drawing that is being removed and replaced by the 350s. Now you simply have a splice and no more tap.
Click to expand...
I completely understand that . Here is my point . I’m trying to determine the location of the existing tap box as it affects my new conduit feeder extension footage to the new location of panels. Soooooo if the existing is considered a tap would the tap box have to be within a certain distance of the panel it’s feeding ?? If so then I know about where the tap box is and I can scale my footage from there to the new panels .
 
Alwayslearningelec said:
I completely understand that . Here is my point . I’m trying to determine the location of the existing tap box as it affects my new conduit feeder extension footage to the new location of panels. Soooooo if the existing is considered a tap would the tap box have to be within a certain distance of the panel it’s feeding ?? If so then I know about where the tap box is and I can scale my footage from there to the new panels .
Click to expand...
If the tap conductors are 1/3 or larger than the ampacity of the feeder then the tap conductor is limited to 25' in length.
 
infinity said:
If the tap conductors are 1/3 or larger than the ampacity of the feeder then the tap conductor is limited to 25' in length.
Click to expand...
So the 2/0 conductors are larger so the box SHOULD be within 25' of panel....regarding existing setup. Question answered. BTW what code section is this in about 1/3 or larger?
 
The ampacity of the Tap Conductor must be 1/3rd the ampacity of the feeder conductor to utilize the 25' tap rule.

Look up the ampacity of 2/0 and see if it's 1/3rd the ampacity of 350mcm.

JAP>
 
I hate to confuse the already confused but technically I believe it's 1/3 of the ampacity of the overcurrent device protecting the feeder being tapped (likely the same as the feeder conductor ampacity but not necessarily)
Beau, This is in 240.21
 
augie47 said:
I hate to confuse the already confused but technically I believe it's 1/3 of the ampacity of the overcurrent device protecting the feeder being tapped (likely the same as the feeder conductor ampacity but not necessarily)
Beau, This is in 240.21
Click to expand...
That's correct. The feeder ampacity would be determined by the OCPD not the conductor size as I think I mentioned in post 11.
 
I mentioned it also in post #8 then worded it wrong in post #15.

Thank goodness for Augie,,, :)


JAP>
 
One thing many people overlook is that it is the length of the conductors, not the conduit or lug to lug distance. Bottom line is, you should really read 240.21. There are 5 conditions for the 10 foot tap rule that all must be complied with. 3 for the 25 foot tap rule.
 
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