How to distribute the load in a dwelling.

[mbrooke]

What is the correct amount of VA to assign to a general purpose duplex receptacle in a dwelling unit? There isn't one, that is why we use our experience to determine how many outlets on a 15 or 20 amp circuit.

Correct, but in code minimum you do have a VA as a whole? A 2000 square foot home is calced at 3va per foot, so 2000x3=6000/120=50/15=3.3 or 4 15 amp circuits. Those 4 15 amp circuits are then distributed evenly around the home.

 

[iwire]

Those 4 15 amp circuits are then distributed evenly around the home.

Maybe.

 

[Strathead]

Originally Posted by mbrooke
Those 4 15 amp circuits are then distributed evenly around the home.



​

Maybe.

If you have a code compliant installation there is no maybe. ​

 

[ActionDave]

If you have a code compliant installation there is no maybe.

There's a big maybe. You have no idea what is going to be plugged in or turned on when the inhabitants begin to habitate.

 

[jumper]

There's a big maybe. You have no idea what is going to be plugged in or turned on when the inhabitants begin to habitate.

Yep.:thumbsup:

 

[Strathead]

There's a big maybe. You have no idea what is going to be plugged in or turned on when the inhabitants begin to habitate.

The code says the circuits will be distributed evenly. When they are installed they are even. If a person plugs loads in that exceed the circuit, that is a usage problem, not an installation problem. I don't like it. I think the code should place some sort of value on receptacles for purposes of sizing branch circuits at least, but in a residence it doesn't.

 

[mbrooke]

There's a big maybe. You have no idea what is going to be plugged in or turned on when the inhabitants begin to habitate.

I would say thats irrelevant. When I said distributed evenly, I did not mean what would actually get plugged in, I meant the actual receptacles and hard wired light fixtures. My understanding is that code does not let you run 3 circuits to dedicated hall outlets and have the remaining 3va per foot circuit handle everything else.

 

[Strathead]

I would say thats irrelevant. When I said distributed evenly, I did not mean what would actually get plugged in, I meant the actual receptacles and hard wired light fixtures. My understanding is that code does not let you run 3 circuits to dedicated hall outlets and have the remaining 3va per foot circuit handle everything else.

We are on the same page. That is what I was implying. The circuits required by table 220.12 are required to be distributed evenly. To me that means a reasonably equal number of outlets on each circuit. iWire then said maybe... But it isn't maybe if you are complying with code. They have to be distributed evenly. That was all I was saying.

 

[mbrooke]

We are on the same page. That is what I was implying. The circuits required by table 220.12 are required to be distributed evenly. To me that means a reasonably equal number of outlets on each circuit. iWire then said maybe... But it isn't maybe if you are complying with code. They have to be distributed evenly. That was all I was saying.

Same here. Unless Iwire was implying there was a loop hole in the code to 220.12 but I doubt that.

 

[jumper]

We are on the same page. That is what I was implying. The circuits required by table 220.12 are required to be distributed evenly. To me that means a reasonably equal number of outlets on each circuit. iWire then said maybe... But it isn't maybe if you are complying with code. They have to be distributed evenly. That was all I was saying.

That may be you opinion, but the code does not say that.

210.11(B)(B) Load Evenly Proportioned Among Branch Circuits.
Where the load is calculated on the basis of volt-amperes
per square meter or per square foot, the wiring system up to
and including the branch-circuit panelboard(s) shall be provided
to serve not less than the calculated load. This load
shall be evenly proportioned among multioutlet branch circuits
within the panelboard(s). Branch-circuit overcurrent
devices and circuits shall be required to be installed only to
serve the connected load.

Futhermore, balancing a resi receptacle is basically impossible.

 

[jumper]

Same here. Unless Iwire was implying there was a loop hole in the code to 220.12 but I doubt that.

Where in 220.12 does it talk about balancing the loads or distributing them evenly?

 

[jumper]

I would say thats irrelevant. When I said distributed evenly, I did not mean what would actually get plugged in, I meant the actual receptacles and hard wired light fixtures. My understanding is that code does not let you run 3 circuits to dedicated hall outlets and have the remaining 3va per foot circuit handle everything else.

Where does it say I can't?

 

[iwire]

Originally Posted by mbrooke
Those 4 15 amp circuits are then distributed evenly around the home.



​

If you have a code compliant installation there is no maybe. ​

Yes there is a maybe, you may well run more and that is often the case.

 

[Strathead]

210.11(B)(B) Load Evenly Proportioned Among Branch Circuits.
Where the load is calculated on the basis of volt-amperes
per square meter or per square foot, the wiring system up to
and including the branch-circuit panelboard(s) shall be provided
to serve not less than the calculated load. This load
shall be evenly proportioned among multioutlet branch circuits
within the panelboard(s). Branch-circuit overcurrent
devices and circuits shall be required to be installed only to
serve the connected load.




I don't see how you can interpret this the way you seem to be. iwire, Jumper, what exactly is your definition of "this load"? I dislike the ambiguity of 210 and 220. For the record, I couldn't find 210.11(B) when I was looking but it is what I was looking form. There is one other way you could look at it. By dividing the square footage by the number of circuits and trying to circuit such that each circuit covers a portion that way, regardless of the number of receptacles, but either way, the three dedicated in a hallway and everything else on one circuit scenario would not be allowed. I am open to a different interpretation, I just don't see it.

 

[Strathead]

Where in 220.12 does it talk about balancing the loads or distributing them evenly?

As iwire pointed out 210.11(B) But there is an implication that it can be interpreted a different way. I will see.

 

[mbrooke]

Where in 220.12 does it talk about balancing the loads or distributing them evenly?

Load Evenly Proportioned Among Branch Circuits.

This is from section 220. 1 15 amp circuit feeding 45 receptacles and the other 3 feeding 3 receptacles is not my idea of evenly proportioned.

 

[jumper]

210.11(B)(B) Load Evenly Proportioned Among Branch Circuits.
Where the load is calculated on the basis of volt-amperes
per square meter or per square foot, the wiring system up to
and including the branch-circuit panelboard(s) shall be provided
to serve not less than the calculated load. This load
shall be evenly proportioned among multioutlet branch circuits
within the panelboard(s). Branch-circuit overcurrent
devices and circuits shall be required to be installed only to
serve the connected load.




I don't see how you can interpret this the way you seem to be. iwire, Jumper, what exactly is your definition of "this load"? I dislike the ambiguity of 210 and 220. For the record, I couldn't find 210.11(B) when I was looking but it is what I was looking form. There is one other way you could look at it. By dividing the square footage by the number of circuits and trying to circuit such that each circuit covers a portion that way, regardless of the number of receptacles, but either way, the three dedicated in a hallway and everything else on one circuit scenario would not be allowed. I am open to a different interpretation, I just don't see it.

The code says I need a branch circuit for every so many square ft. It never that says the circuit is limited to that much area or must cover that much area.

 

[mbrooke]

The code says I need a branch circuit for every so many square ft. It never that says the circuit is limited to that much area or must cover that much area.

Correct, but I still cant see uneven distribution of load, or at least devices that may support load.

BTW, thanks for the new thread!

 

[jumper]

Correct, but I still cant see uneven distribution of load, or at least devices that may support load.

BTW, thanks for the new thread!

Thank iwire for the new thread.

Now as to equally balancing/distributing the load; what is the load of resi receptacles?

Also, assuming switched lighting receptacles for all rooms save bathroom and kitchen, and outside lights; how large do you think my lighting load is gonna be?

 

[iwire]

Now that we have our own thread I will say this.

To me this topic is ridiculous, worthless, meaningless.

It's a house, nothing is that critical, circuits overlap, areas have undefined boundaries.

I am out if this.