Feeders to 3-plex residense

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iwire

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Massachusetts
It's just so much easier without all those LBs!!! If I did attempt to drill and it actually worked out. What would you guys recommend I seal the holes with?

I would use the LBs.

I would not drill through the foundation or footing due to the water issues mentioned above.

As far as the LBs, what size conduit and conductors are you running?

What about grounding electrodes at each building?
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
Out of curiosity why do they need 100Amp feeder for the units?? That is a pretty large feeder for per unit of triplex.
 

tbakelis

Senior Member
I will be running 1 1/4" PVC conduit with #3 copper (2 hots and neutral) with #6 ground.

All 3 of this buildings share a common roofline/breezway... so technically it could be considered 1 structure. IF it was classified as 1 structure... does that eliminate the requirement for disconnecting means prior to individual units... as well as eliminate the need for a grounding electrode at each unit?
 

tbakelis

Senior Member
Out of curiosity why do they need 100Amp feeder for the units?? That is a pretty large feeder for per unit of triplex.

The owners of the property had someone upgrade their main service to 400 Amps. 2 of the units have existing 50 Amps servicing them each (of which one underground conduit has started to rot which may be driving the upgrade). They have all electric appliances in each unit with possible AC installed later.

I got the call to give a quote on upgrading two of the units to 100 Amps..... so that's what I'm doing :)
 
Please excuse my novice. Why not use the LBs; aren't they like $2 each?
And if they are taps, don't they have to terminate into an over load device anyway? 241.(B)5(2)
What about Panels for each unit? that would eliminate the $2 LB. As was suggested run 200 amp to the first, then 100 to the other?

Again; I am asking rather than suggesting as I no little of practical application; I really want to understand.
 

tbakelis

Senior Member
Please excuse my novice. Why not use the LBs; aren't they like $2 each?
And if they are taps, don't they have to terminate into an over load device anyway? 241.(B)5(2)
What about Panels for each unit? that would eliminate the $2 LB. As was suggested run 200 amp to the first, then 100 to the other?

Again; I am asking rather than suggesting as I no little of practical application; I really want to understand.

I was trying to avoid the LBs for pulling purposes (1 1/4" lb are like $10+ :).. There will be 5 LBs over a 150' run.

I can't use 200 amp breaker at the main. Current setup will only allow 125A max

Each unit has or will have panel within the unit that is the home of the branch circuits.
 

ActionDave

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Durango, CO, 10 h 20 min from the winged horses.
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Licensed Electrician
Please excuse my novice. Why not use the LBs; aren't they like $2 each?.....
It is not about cost. When you use an LB you have to pull enough wire out of the LB to reach your final destination and then pull all that wire back into the the other hole in the LB. That can be a pain sometimes especially if there is more than one in the conduit run.
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
I was trying to avoid the LBs for pulling purposes (1 1/4" lb are like $10+ :).. There will be 5 LBs over a 150' run.

I can't use 200 amp breaker at the main. Current setup will only allow 125A max

Each unit has or will have panel within the unit that is the home of the branch circuits.

5 LBs, 150' run with #3 copper:eek:hmy::eek:hmy:

Sounds like a time and labor intensive pull.
 

tbakelis

Senior Member
It is not about cost. When you use an LB you have to pull enough wire out of the LB to reach your final destination and then pull all that wire back into the the other hole in the LB. That can be a pain sometimes especially if there is more than one in the conduit run.

Exactly! That's what was driving me to the brink of wanting to drill through the footer of the structure....
 

tbakelis

Senior Member
Please do not ever drill through a footer. You may drill through a stemwall but not a footer. The stemwall is what sits on top of the footer.

I have never done it. Was just wondering about it because of the need for 5 lbs in this 150 foot run.
 

Little Bill

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Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
Yep, next week it will be 5 LBs for one run and 3 for another.

Ughhh

Did you not think this was a good idea?


Another way to do this is to run a 200 amp feeder to building 2 and install an exterior panel. From there just LB down to just below the joist and pipe thru the crawl space to the other side and lb down into the ground. This keeps all holes above ground and you only have 2 lb's.
 

Little Bill

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Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
The main panel will not accept a 200 amp breaker the way it is. I'm pretty sure 2 pole square D QO maxes out at 125 A

I was thinking you would come off the 400A meter which should have double lugs or could be installed. Or maybe the panel could have feed through lugs added if it is not already a feed through.
 

kwired

Electron manager
Location
NE Nebraska
5 LBs, 150' run with #3 copper:eek:hmy::eek:hmy:

Sounds like a time and labor intensive pull.

VS the time and labor spent drilling through the footing for what OP originally proposed to do?


I still am not seeing why we need 5 LB's. Are we running the feed to unit 3 in and back out of unit 2" If so, why?

If these all have a common roof - most areas will consider it one structure.

My install - I'd consider changing out service equipment - I know it is relatively new, but look at bigger picture.

Possibly install two mains, one 100 amp to supply the loadcenter in the unit where the service is, and a 150 or 200 amp main (totally dependent on load calculations which one is selected) and run 150 or 200 amp feeder to middle unit - tap that feeder to supply the middle unit, then tap to the third unit - outdoor taps can be unlimited in length.

Other details may change this approach, but is what I would be thinking of first.
 
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