Proper wiring for INSIDE of workshed.

[Guido]

This is for a stand-alone workshed. I plan on running a single 20A circuit for various receptacles (some of them switched) and ceiling lights.

1) Is there a maximum number of receptacles I can place on this circuit? Obviously I won't be using them all at once, but since I'm wiring from scratch I would rather put a few extra, than regret not having enough.

2) I know for a house there are codes as to placement of receptacles & switches (distance from the floor and each other), but what about a workshed? Can I put them wherever I want? Including a switch on the ceiling?

3) Some items will be permanently plugged in (grinder, drill press, etc), does this change anything?

4) I plan on putting receptacles on the ceiling and having all my lights plugged in (not hard wired). Is this OK?

5) Are there some items (power tools, flourescent lights, etc.) that should NOT be on a GFCI protected circuit?

[Homer]

This is for a stand-alone workshed. I plan on running a single 20A circuit for various receptacles (some of them switched) and ceiling lights.Under Canadian rules, if you use a 20A circuit then you must

1) Use 20A rated receptacles and switches and you will be limited to plug and cord connected lighting. (no light fixtures allowed on a 20A circuit)

2) Your receptacles and GFCIs will need to be the 20A T-slot variety.

3) You need to have a disconnect switch in the shed. That can be a 20A rated switch placed in the shed that will cut the circuit power.

Is there a maximum number of receptacles I can place on this circuit? Obviously I won't be using them all at once, but since I'm wiring from scratch I would rather put a few extra, than regret not having enough.The limit is 12 outlets per circuit.

I know for a house there are codes as to placement of receptacles & switches (distance from the floor and each other), but what about a workshed? Can I put them wherever I want? Including a switch on the ceiling?I don't see why not. Just make sure your disconnect switch is easily accessable.

Some items will be permanently plugged in (grinder, drill press, etc), does this change anything?If any of these items will draw more than 50% of the circuit (10A in this case), then they would need their own circuit. You may want to consider a multiwire circuit to the shed instead (gives you 2 circuits instead).
I plan on putting receptacles on the ceiling and having all my lights plugged in (not hard wired). Is this OK?Sure, as mentioned earlier with a 20A circuit in Canada, you can only have plug and cord connected lights anyway.

Are there some items (power tools, flourescent lights, etc.) that should NOT be on a GFCI protected circuit?Since everything is powered with receptacles, I would protect them all.

Homer

[Guido]

Thanks for the reply.
Wow, I'm so glad I came here - it seems very different than the US code.

How would things change if I only run 15A?

When you said "If item draws more than 50% current..." does this apply even if the item is not permanently plugged in? And does it apply to a 15A circuit as well?

I'd love to run 12/3 wire with 2 20A circuits, but my main panel is already full. It's 100 amps and I have a basement apartment. It's a Commander panel model, model B/BC and uses Cutler-Hammer, bolt-on type QBH breakers. I'm having trouble locating 1/2 size breakers for this panel.

Is it legal in Canada to run 2 separate circuits to a detached building?

[joed]

I think I would leave the lights off the GFCI so you are not in the dark if it trips.

[Homer]

How would things change if I only run 15A?You could then have light fixtures on the circuit.

When you said "If item draws more than 50% current..." does this apply even if the item is not permanently plugged in? And does it apply to a 15A circuit as well?If the item is not permanently fixed in place then you can argue that this doesn't apply as it may not even be there the next day!

Is it legal in Canada to run 2 separate circuits to a detached building?You can't run 2 separate circuits to a detached building. However, you can run ONE 3-wire multiwire circuit to a detached building. This can power a subpanel or directly power two 120V circuits.

Homer

[mdshunk]

Sounds like you're due for a subpanel. There's no such thing as a half size QBH breaker. To keep from buying one of those expensive QBH breakers, you might choose to use the existing range breaker and use that for the subfeed breaker and set the new subpanel right next to the existing panel. Then, you can refeed the range (or whatever you chose) from the new subpanel, and then pull your new shop circuit out of this new subpanel. You might also choose a more readily available subpanel style, such as Cutler Hammer's 'CH' or 'BR' or whatever else is easy to get in Toronto.

Oh... One more thing... somebody's bound to point out that since your 100 amp panel is full, you might be wise to do a 'demand load calc' for the whole dwelling. It's possible that you're due for a whole service upgrade. Check out the link in the green and yellow boxes above.

[Guido]

You could then have light fixtures on the circuit.
If that's the only difference then no big deal anyway since I plan on providing receptacles for the lights anyway (so I can easily switch from flourescents in the summer and incandescent in the winter). And I'll still run 12GA even if I'm only running 15A. The only difference will be receptacles and breaker. I can live with that.


If the item is not permanently fixed in place then you can argue that this doesn't apply as it may not even be there the next day!
Thanks! I should be safe then.


You can't run 2 separate circuits to a detached building. However, you can run ONE 3-wire multiwire circuit to a detached building. This can power a subpanel or directly power two 120V circuits.
That's what I figured.

On a side note - if I use a 20A wall switch as a main cut-off for the entire shed, do I need a special switch? I read somewhere on the net that they have "HP Rated" switches that must be used whenever an electric motor is on the circuit. I asked the guy at HD about this and he gave me a funny look.

[Guido]

Sounds like you're due for a subpanel.
I already have a subpanel... and it's full too :(
It powers my clothes dryer and central A/C.
If it's feasible to install another panel, can I add another one off the main panel (I physically have space for it), or should I just get a larger one to replace the existing subpanel?


Oh... One more thing... somebody's bound to point out that since your 100 amp panel is full, you might be wise to do a 'demand load calc' for the whole dwelling. It's possible that you're due for a whole service upgrade. Check out the link in the green and yellow boxes above.
That's a good idea - I'll do it just to be safe. The circuits currently are pretty well balanced (load-wise). MY father in law used to own an electrician business and said nothing looks overloaded, but he hasn't been in the business for a while and is not up to speed with the codes.
The previous owner already upgraded from 60A service.

I currently have a MSWord file listing every breaker in my panel and what is connected to that circuit. If anyone has some spare time to review it and see if anything stands out, I'd appreciate it.

[Homer]

On a side note - if I use a 20A wall switch as a main cut-off for the entire shed, do I need a special switch? I read somewhere on the net that they have "HP Rated" switches that must be used whenever an electric motor is on the circuit. I asked the guy at HD about this and he gave me a funny look.You only need a 20A rated switch. Don't worry about HP ratings for the switches unless you are hardwiring a motor to the switch or have a dedicated circuit for a motorized appliance. In your case, you basically have plug and cord connected appliances and lights with no appliances fixed in place.

Homer