Is there anything in the book where I can't feed another 200amp from a 200amp?

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electricblue

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Location
Largo, Florida
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EC
Is there anything in the book where I can't feed another 200amp from a 200amp? I see homeline has a
HOMELINE? 2-pole High Amp Circuit Breakers and
225 A Sub-feed Lugs
Single-phase Applications Only
 

charlie b

Moderator
Staff member
Location
Lockport, IL
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Retired Electrical Engineer
As long as the total calculated load on each panel does not exceed that panel's rating, you can feed any panel from any other.
 

electricalist

Senior Member
Location
dallas tx
Is there anything in the book where I can't feed another 200amp from a 200amp? I see homeline has a
HOMELINE? 2-pole High Amp Circuit Breakers and
225 A Sub-feed Lugs
Single-phase Applications Only
Nice that sounds like a cost effective panel a customer of mine needs. Do you have a part number if possible.
 

Little Bill

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Location
Tennessee NEC:2017
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Semi-Retired Electrician
Is there anything in the book where I can't feed another 200amp from a 200amp? I see homeline has a
HOMELINE? 2-pole High Amp Circuit Breakers and
225 A Sub-feed Lugs
Single-phase Applications Only

As long as the total calculated load on each panel does not exceed that panel's rating, you can feed any panel from any other.

Depends on if you're talking about feed through lugs or feeding off of a breaker in the load section of the bus.
It's not an NEC thing but a mfg thing as most bus stabs/breaker mounts are not rated for 200A.
 

Dennis Alwon

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Location
Chapel Hill, NC
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Retired Electrical Contractor
If the lugs are feed thru and the main breaker is 200 amps why would it matter what the lug is rated? Lugs are not usually rated in amps but rather in wire size.

If you use wire rated for 200 amps and feed another panel that is 225 amps it does not matter since the 200 amp breaker is protecting the wire and panels. Of course, as Charlie stated, the calculated load does matter
 

kwired

Electron manager
Location
NE Nebraska
Can a 200 amp rated panel have 225amp feed through lugs or would feed through lugs be rated the same 200 amps as the bus?
What often happens is you have same components installed in both a 200 and a 225 amp panel - just the main breaker is what is differnt, saves manufacturer some cost on needing to have a separate production line/inventory of parts for certain finished products, same goes for 125 amp vs 100 amp panels in many cases - many times are same components just a different main breaker. If panel has feed through lugs they may (and often are) able to accept larger then 200 amp conductors- but they will still be limited to 200 amps if you have a 200 amp main breaker. The Square D panels mentioned likely have lugs that accept up to 300 kcmil conductors in both the 225 and 200 amp panels.
 

kwired

Electron manager
Location
NE Nebraska
Nice that sounds like a cost effective panel a customer of mine needs. Do you have a part number if possible.
HOM816M200FTRB, also available with 150 amp main - but is essentially same thing with different main, QO series also has similar panel but is also available with 125 amp main. Unfortunately all of them only come in a NEMA3R can, but work great for service equipment on exterior of house and 200 amp subfeed to the interior - or even service on an outbuilding and 200 amp feeder to the house.

Also work great for mobile/manufactured homes that need a 200 amp feeder yet need breakers for accessory buildings/structures.
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
If your panel did not come with feedthrough lugs you can use one of these or similar. You basically create your own feed through lug. But it may be considered a branch and limited to less than 200Amps (pending instructions of the panel)

View attachment 12510
 

kwired

Electron manager
Location
NE Nebraska
If your panel did not come with feedthrough lugs you can use one of these or similar. You basically create your own feed through lug. But it may be considered a branch and limited to less than 200Amps (pending instructions of the panel)

View attachment 12510
Most subfeed lug kits of similar design to what you pictured take four pole spaces if they are rated for over 125 amps. You probably could plug one of those into a 200 amp panel and supply a "feeder tap" though. More likely it is about as cost effective or at least something more readily available to just get a 100 amp breaker then it is to use the sub feed adapter. To use for a 150 or 200 amp sub feed becomes more worth considering such a device - can't say I have ever priced or used one for miniature breaker panels - have used similar lug devices in I-Line panels though, but that is a little different ballgame with those panels then it is with "loadcenters".
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
If your panel did not come with feedthrough lugs you can use one of these or similar. You basically create your own feed through lug. But it may be considered a branch and limited to less than 200Amps (pending instructions of the panel)

View attachment 12510


I really doubt that 200 amps would be allowed on a buss stab so if it were rated less you would not be able to put 200 amp conductors under the lug. If you used smaller conductors then the tap rule would come into play.

I also agree with kwired 100 amp breaker would be a better solution if the load allows
 

GoldDigger

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Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Most subfeed lug kits of similar design to what you pictured take four pole spaces if they are rated for over 125 amps.
So, in that case the total current would be spread out over two stabs per pole? That could, I suppose, allow a 200A subfeed to be attached to a 200(+) amp bus even though the breaker limitation based on stab current might only be 100 or 150A?
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
Google found me a couple relevant results for "200A sub feed lug kit..."

https://www.platt.com/platt-electri...-Blocks/Eaton/BRS225/product.aspx?zpid=270025
(Note: Picture is not accurate, specs say it takes 4 spaces.)

Also...
http://static.schneider-electric.us...ion/Miniature Circuit Breakers/0750DB0301.pdf

So, in that case the total current would be spread out over two stabs per pole?...

Yup, most definitely.

I've seen a lot of main breakers configured this way, but I wasn't aware these lug kits and breakers were available. It could possibly really save my ass in some situations where I would like to add distribution near a main-breaker-only service panel so I can install PV. Yay. :D
 

templdl

Senior Member
Location
Wisconsin
When I see questions similar to this the OP seems to avoid stating if this is a theoretical application or if it is a real life design that is being considered. If it is a design being considered then is it a practical design even though the load calculated are computed correctly the cable sized and protected as well as the main panel having the capacity to feed the 2nd 200a panel.
Being a good design though is somewhat questionable.
 

electricalist

Senior Member
Location
dallas tx
When I see questions similar to this the OP seems to avoid stating if this is a theoretical application or if it is a real life design that is being considered. If it is a design being considered then is it a practical design even though the load calculated are computed correctly the cable sized and protected as well as the main panel having the capacity to feed the 2nd 200a panel.
Being a good design though is somewhat questionable.
I have a customer that has a house attached to a very large garage on the right. Just to the right front of the garage is a poco pole that feeds across the garage to the house. Looks bad. They want the garage to be a game room / shop. I think this would be ideal for the type of panel here. Move service to corner of the garage and feed the 200 amp panel in the house from the garage.
 

templdl

Senior Member
Location
Wisconsin
I have a customer that has a house attached to a very large garage on the right. Just to the right front of the garage is a poco pole that feeds across the garage to the house. Looks bad. They want the garage to be a game room / shop. I think this would be ideal for the type of panel here. Move service to corner of the garage and feed the 200 amp panel in the house from the garage.

It looks as if the first 200a panel's (service entrance?) rating is being used to feed the 2nd 200a panel, that the actual load on the first panel may be well served by a 100a panel or even less if it wasn't needed to be used to feed second 200a panel. Personally I see no issues
 

Strathead

Senior Member
Location
Ocala, Florida, USA
Occupation
Electrician/Estimator/Project Manager/Superintendent
I have a customer that has a house attached to a very large garage on the right. Just to the right front of the garage is a poco pole that feeds across the garage to the house. Looks bad. They want the garage to be a game room / shop. I think this would be ideal for the type of panel here. Move service to corner of the garage and feed the 200 amp panel in the house from the garage.


And to summarize all of the above...

The loads connected to a feeder can't be greater than the feeder's ampacity, and/or exceed the rating of the breaker that protects that feeder. This is based on various sections of the code, including article 315, motor conductor sizing, transformers etc. This is also generally applicable to outlets and equipment as well. For example, it is illegal to plug a typical Greenlee smart bender in to a 15 amp receptacle. (I use this because I have seen it violated more times than I can count).

So, theoretically, you could feed 10 panels using feedthrough lugs, as long as the feeders and equipment didn't exceed the rating of the protecting breaker and the calculated load per the NEC was also less than the rating of the feeders and breakers.

This could seem unlikely, but not so much. Say you had a lab, where they wanted to be able to turn off every receptacle on a table individually and they had 100 table top receptacles. Each one was only expected to carry a small electrical load.
 

Jortz

Member
Location
Franklin sq. NY
My questions are with a crappy aluminum bus bar such as in BR, Murray and Homeline panels, are the stabs capable or carrying any load above 100 amps?
My personal opinion is a set up like this with any load in excess of 100 amps is asking for bus bar failure.
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
My questions are with a crappy aluminum bus bar such as in BR, Murray and Homeline panels, are the stabs capable or carrying any load above 100 amps?
My personal opinion is a set up like this with any load in excess of 100 amps is asking for bus bar failure.
As mentioned earlier, a 200A feed would require that each pole connects to two stabs, taking up twice the panel space.
 
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