ECN Forum Forums Code Related Discussion Canadian Electrical Code Topics Appliance Garage

First do you need a 20 amp receptacle? Not if the appliance is less than 1440 watts. Appliance garage receptacles are not counted as counter plugs.
Most limit switches are rated 10 amps or less and i think there is at least 1 door jamb switch rated at 15 amps. Trouble with these switches is they are not suitable for anything but a hinged door and usually must be installed in the hinge side to ensure the plunger is activated. We require the power to be off when the garage is even partly closed and that cannot be done with a door jamb switch.
A limit switch and small contactor in a proper enclosure is what is needed but some inspectors will let you use a relay inside a 6X6X4.

What's a proper enclosure for a relay? It was my understanding that CSA approval wasn't needed as long as the box didn't have control buttons (etc.) cut into the cover. I've seen relays, transformers, fuses, programmable controllers, contactors and time clocks put into electrical boxes. If our inspectors started enforcing this, it would start a whole new industry in Saskatchewan, a lot of it fixing my work.

I guess this is a common question and there is no simple answer but I will give the CSA speech
Any assembly of approved components is a new product. Just sticking a relay in an electrical box does not make an approved control. There might have to be a barrier if there are mixed voltages. What about the heat produced by the relay? what environment? Did you correctly allow for wiring space? Is O/C protection required?
I recognize that many inspectors and electricians look at a simple cube relay in an aluminium box or a couple of stacked 4" boxes and extension rings as not worthy of a field approval.
It is a pretty common practise but is not covered by part 2 or part 1 as an approved assembly.
The legal way is more onerous and frankly I doubt that many jurisdictions would require the field approval.
If you mix voltages like class 2 for the garage switch and stuff that in a general purpose box I better see a barrier or product approval label. 120 volt relay and a general purpose box with lots of room and I might not look closer.
Every controls manufacturer should have an enclosure for one of their contactors. that is the code compliant way but as you noted it is not a common requirement by inspectors.