How does an electrician wire multi-floors

[peter d]

Here is the riser method, conductors are encased:

http://forums.mikeholt.com/showthread.php?t=159120&p=1542199#post1542199


The method I have in mind also has the conductors enclosed, but the taps are in the attic and run down to the subpanel.

Well I learned something today. :blink:

 

[mbrooke]

Well I learned something today. :blink:

Its a very efficient method in many regards. I know the riser panels are legal, but if the attic method is still legal the OP can save a ton on wire and breakers given a bit more labor.

 

[mbrooke]

I think its still doable assuming nothing changed. Here is a white paper on tap rules:


https://library.e.abb.com/public/9e7ae3c8094341488549ef5a3e791064/ABB-1742-WPO_NEC_Tap_Rules.pdf

 

[kwired]

There is no limit to how many times you can tap a feeder. At some point you may run out of capacity on the feeder.

If you can keep the taps under 10 feet you can have a pretty good sized feeder as taps can be 1/10th the ampacity of the feeder overcurrent device. Tap to 100 amp panel could come off a 1000 amp feeder- sort of unlikely to tap off a 1000 amp feeder but a little more likely to do so off a 400 or 600 amp feeder.

Can't go with 25 foot tap with 100 amp conductor off a 400 amp feeder unless outdoors.