I am assuming the 12' rule of the receptacle placement also applies to a commercial office.
And the # of receptacles on a 20A circuit also applies to a commercial office?
Or both of the above are only for a residential setting?

Thank you
Edward

You don't need any receptacles in an office.

Each receptacle in a commercial building counts as 180 VA.

There is no limit to the amount of receptacles on a circuit in a dwelling.

Thanks Ryan.

So in an office situation there is a limit on #of receptacle per circuit.

Edward

Doesn't office count as commercial space???

Thanks
Edward

Yes, an office is a commercial space, therefore the 180VA rule of 220.14 applies.

For example, how many receptacles can be on a 20 ampere branch circuit?
20A*120V=2400VA
2400/180=13 devices on a 20 ampere circuit.

Thanks Ryan

I thought the spacing was 6', and not 12'.
210.52(A)(1) States the spacing to be 6' instead of 12'. Correct me if I'm wrong.

The rule requires that no point on the floor be more than 6' from a receptacle.

If you place the outlets every 12' than no point along the floor line will be further than 6' from at least one receptacle.

To be clear for everyone reading this thead, the rules in 210.52 only apply to dwelling units. There are no receptacle spacing rules for other occupancies.
Don

OK, I've not been required to do much in the residential area, so I feel kind of dumb here. So what you're saying is, I can measure any place on a floor, any where in the room, and it should be no more than 6' from a receptacle, OR, is it measured any where along the line at the bottom of the wall, even if you measure from one wall across a corner to another wall, should be no more than 6'?

Just a little note of explaining the reasoning behind the code, as it was explained to me, long ago.....

As we have absolutely no idea where Suzy Homemaker will place her furniture THIS week, the code assumes a receptacle can be needed almost anywhere; hence the spacing rule, which wants a receptacle to be in reach of a floor lamp (standard 6 ft cord) almost anywhere. Since Suzy only has a few lamps, and isn't drawing a whole lot of current, the code does not consider it necessary to limit the number of receptacles on a circuit (in a home). The more, the merrier, I guess.

Contrast this to the assumptions behind your typical office design. It is assumed that the cheap fools who lay out offices know what they are doing, and can be trusted to call for only the receptacles that they need. Since these are necessary receptacles, the code assigned a minimum load to each- in effect, limiting the number on any one circuit.

Code aside, I try very hard to place receptacles where they will be wanted (generally, I want them next to the sofa, and not behind it!), and size the circuits for a realistic guess as to the loads that will be applied.

Remember- from the outset, the code warns us against using the code as a design manual!
Rather- do your design, then check it against the code!

Neither, if you meant "diagonal" when you said "across a corner". This is strictly along the wall/floor line, the perimeter of the room.

Any point along the wall must be within 6' of a receptacle. Going around inside or outside corners is okay, but not diagonally away from the wall.

I call it the "6-12-12-6" rule, and on kitchen counters, it's the "2-4-4-2" rule. The former applies to any wall space 2' or wider, and the latter to 1' or wider.

"the code does not consider it necessary to limit the number of receptacles on a circuit (in a home)." - However not keeping to common sense in limiting yourself, could set you up for some call backs.

Ryan I thought you can only load a circuit to 80% and that works out to be 10.666.. recepticals which = 10,
Thats what I have been taught.Was any one else taught this.

Thanks John

Bossman you can load a circuit 100% if you want.

That changes if the loads are continuous loads.

Receptacles are not likely to fit the NEC definition of continuous load.


Do you picture a multi outlet circuit to be loaded to 20 amps for 3 hours or more?

The code gave the outlets a 180va value so it is continous.

What code section do you believe tells us the 180 VA is continuous?

It is not, it is just a figure for calculations.

Then why stop at 13 plugs put in a 100 if its only for calculations.
I dont have a book at home right now but I remember this in code classes in the past and thats the way I was taught, And I definetly could be wrong its happend before. Once! Ha Ha

John

iwire, I looked and had my code book here and found the hand book too and the example shows 13 outlets so now its 2 times wrong at this rate I may not trust myself anymore.
Theres nothing better then looking before you talk. I should wash my feet more.

John.

Bossman: It happens to the best of us. But look on the bright side...you aren't going to forget this rule now

OK. Let's see if I've got this now. Say in a bedroom, common sense would tell me to put a receptacle on each side of where a bed may go, etc., and after that I would fill in the gaps to make sure that no point along the wall lines would have a space no longer than 6' between receptacles? I used that example because I'm about to add a bedroom to my house.

I agree that an unlimited number of receptacles on a circuit is asking for poor performance from the circuit.....and MANY locales have limited the number of receptacles allowed on a residential circuit.

It is no surprise that, by strictly doing the code minimum, you may end up doing some silly things.

Take this 6-12 rule as it is usually applied. Enter a room, mark off 6 feet, then 12 ft, etc...all around the room. Since many rooms are somewhat close to being 12 ft x 12 ft, the result of this method is that you run the absolute minimum number of receptacles- but the all end up in the middle of the wall. You've almost guaranteed that every one will be behing furniture.

A better result happens if you place a receptacl right by the door, then start counting off 12 ft. Since doors are usually near the corner of the room, you wind up with a receptacle on either side of the bed (or sofa)....at the 'expense' of ONE additional receptacle in each room.

No, that no point along the wall is more than 6' from a receptacle, in either one direction or the other.

Start at a doorwy; the first receptacle must be within 6'. The next one must be within 12' of the first one. The last one must be within 6' of the next doorway.


Picture yourself trying to plug in a lamp with a 6' cord. As you move along the wall, just as you move 6' from the last one, the next one must be within 6'; that's 12' between them.

When I did my bedroom I put three 4x4s such that in the 2 logical bed locations I could have a quad on each side. Those got "smurfed" to the oversize square box with a mud ring down to a double by the door. Originally I had with 3 ways controlling a switched duplex at each bed location and the overhead, controlled at the door or bed. When we (read "she") change our mind it is trivial to change stuff. You always seem to run out of outlets by the bed.
I stuck in one of those solid state night lights in half of the quad in the one that wasn't behind the bed.

the spacing rule was explained to me like this: draw two lines on a piece of paper, about 6inches apart. let the distance between them represent 12 feet. Now, draw another line exactly halfway, to represent you. If you move in either direction, you are within the 6ft "zone" of that receptacle, Thus the 12 ft spacing.

The 180 VA rule is only for calculations. As far as branch circuit load limitations,where there is any combination of non and continuous loads, it shall be sized at 125% of the load, or 80% of the circuit rating however you look at it. Unless you have some kind of rated assembly that has a 100% rating.

Xthedge If I were wiring my own bed room I`d put a min of 2 outlets per wall the long side maybe 3 the code is the minimum.If I were wiring it would not want the min standards for my house or anyone elses for that matter. Its the cheap a** general contractors who have us wiring a house for nothing and putting less than desired outlets and switches. Sorry if any GC`s here.I think a good electrical job can help sell a house just like the tile and cabinets can.I hate wiring to code so I can compete with everyone elses price.Man that felt good. Vent,vent,vent

I blame the real estate sales people. By and large they are idiots who really do not understand the product they sell.
If they sold the added value of having receptacles, lights, switches etc where you will really need them there would be enough money in the job to do it right.
Unfortunately they will sell fancy knobs on the cabinets and never mention the extra "infrastructure" nobody looks at ... until they are standing there with a plug in their hand and no receptacle to put it in.

The one that bothers me is they don't sell the value of a combo low voltage and receptacle box. Anywhere you have a cat 5 or TV cable, you will need a receptacle. Why would they ever do it any other way? Unfortunately nobody puts that extra buck or two into the job.

Since people are saying what they like rather than what the code requires:

I put recepts where I want them: A bit away from the center of walls, and not directly under windows.

It is a fact of life: No matter where you place the recepts: there is only a need for 1 recept and you have missed it my 5' and it needs to service 5 devices.

Reel-Break,
I totally agree.