Please allow for my ignorance... I am not familiar with Canadian rules; perhaps someone could explain something to me.
I am told that many Canadian EC'c have licenses that limit their practice to 200 amp services, or smaller.
A common type of housing is having four apartments in one building, with each apartment receiving a 100 amp service. To circumvent the "200 amp" limit, contractors are running two service masts into a common gutter, that in turn feeds the 4 disconnects.
It seems to me that four residences do NOT require 400 amps of service. If you did your load calculations, then the de-rating factors for multiple services..... it looks to me that you would most likely be able to serve all four services with a single 200 amp service drop.
I guess it would depend on the province, in Alberta we have a master electrician licence, that allows electricians to work with any voltage or amperage. There used to be a restricted master electrician license, that only allowed electricians to work up to 200 amps and 300 volts. I don't believe this restricted licence is available to new electricians anymore, however old licences can still be renewed, I think. Your question about a fourplex residential service, no it would not be served with a 400 amp service, most times a 200 amp service would be okay according to code.
In ontario the master license is just code and business related or so ive been told.I think the 442a and 309a is limited to 600v and ??a.I work up to 1200a and have never been questioned by inspection.Anything over 700v needs a high voltage license.Please correct me if im wrong. The poco comes in and shuts it down and grounds the busses so we can do our spring cleaning on the 4160v, they do the 27000v system themselves. What i found stange was when they came in to one of our sites to install the new pulse meters they required me to shut down the 600v 1200a standard sevice and transfer the emergency loads to generator.I couldn't get them to open the switch at the pole for nothing.I got the impression that the didn't trust it. cheers
[This message has been edited by frank (edited 07-15-2006).]
200A limit?? Never heard of that.. I always thought they ran 2-200A services like what you see in that picture for ease of install... Think of it, would you rather run a pair of standard 2 1/2" masts and install 3 x 3/0 R-90 conductors in each OR would you prefer to run some 3 or 3 1/2" pipe up a wall, have it strapped to an angle iron at the top for support and have to pull a trio of 500 Kcm cables up through that??? Not to mention having to bend said 500 around in the gutter... Meh, I think I will take the first option just so I dont have to bend any 500 Kcm around.. ( And besides TWO smaller services strapped to the wall would look neater than one big honkin ugly one)..
Here in British Columbia there is 3 classes of contracting tickets Class C is restricted to 200 amps single phase 300 volts class B 750 volt 3 phase Class A no restrictions Hope this explains the subject
Doug, I am curious about your comment re the mechanical protection. It is probably a bit of a judgement call, and I know those are service conductors, but they are teck and shouldnt require mechanical protection. If so, then just about every service with conduit out the bottom of the meter base needs mechanical protection based on most meters being within 5 feet or so of the ground.
The other thing they are service conductors and that window does open. Not sure if thats only for triplex installations though. See those brand new stairs... the last ones were taken out by a car accident. Ripped all the railing out and I guess insurance piad for new concrete stairs too.
[This message has been edited by dougwells (edited 07-18-2006).]