Circuit Loads

[TrueWest]

When planning circuits, what do you allow for outlets when figuring the total load? I have a 15A circuit with very little on it, but 8 outlets. Is there a standard amp draw assumed for outlets?

[Roy Mottola]

Yes, for general lighting outlets 1.5 amps per outlet or max 10 outlets on a

[Greg]

It really depends on where you live (Canada/US) and if this is a home or commercial. There are no rules on general lighting outlets per circuit, only the load per square foot of space covered (3va/ft2) if this is US residential. You do have "design" concerns to serve the load you plan on using.

[HA HA Budys Here]

No. The number of outlets on a residential convenience circuit is unlimited.

The number of circuits is calculated at 3 watts per sq. ft. The (minimum) number of outlets is determined by linear wall space.

So if you end up with 5 circuits and 50 outlets, plan on 10 outlets per circuit. If you end up with 60 outlets, figure 12 per circuit.

And it's perfectly legal to shift the number of outlets to ease the job or facilite better distribution based on known usages - like put 14 on one, but only 6 on another.

[Dave]

Yes. In Canada, the max residential is 12 outlets per circuit, max predicted

12 amps on a 15 amp circuit, and we assume about 1 amp per average duplex receptacle. A bathroom where you might use a hairdryer or other high consumption device would require more latitude.

Dave

[Greg]

Bathrooms, kitchens and laundries require 20a dedicated circuits (2) in kitchen. The original question was about the general lighting circuits. In the US these are distributed equally based on the VA per square foot (3va) and the receptacles are placed based on the average length of a lamp cord (6 feet). The objective is not to have any wall space 2' or longer, not more than 6 feet from a receptacle and that no cord will have to be pulled across a door opening or other hazard. There is no limit on how many receptacles that is since they assume you will not really use them all anyway. It is purely based on the projected load of 3va per square foot. This is just the minimum. You can always put in more. We plug in a lot more things than our parents but generally they use less power. Large loads are usually put on dedicated circuits.

[Dave]

I have heard about those 20 amp circuits, but they are rarely used in Canada (too bad). Here, for a kitchen the duplex receptacles are usually wired with 15 amp circuits, but the upper and lower plug of the receptacle must be on separate circuits. For a bathroom, 15 amp GFI-protected plugs are the norm. Almost all home wiring is done with 14 gauge romex, not the 12 gauge wire that you more commonly use in the US. I like the increased versatility you have, unfettered by the worry about exceeding a maximum fixture count during the planning stage. On the other hand, if you later discover that a circuit is overloaded and breakers are tripping, you then have some remodeling to do.

You make a good point about the trend toward increasing use with each generation. Whether that trend will continue is hard to say.

Dave

[Greg]

We plug in a lot more stuff but it is generally lower wattage than our parents. A new TV is really more like a big lamp. You could cook a chicken in one of those old tube sets. Central heating and A/C has taken the place of space heaters and window shaker A/C units. People are finally starting to discover compact flourecent bulbs.

[Chris Lewis]

According to Dave :

Recent code changes in Canada are going to make them a lot more common - at least in kitchens.

Up until recently, kitchen counter outlets could _only_ be split duplex 15A dual circuits. New GFCI requirements for kitchen counter outlets (very much like the US') mean that you either have to use dual GFCI breakers for them (very pricey), or, use US-style 15A/20A 12ga circuits with a GFCI outlet (just like the Americans have for a while).