40 amp sub panel

[garygnew]

Ok, Sorry to keep taking up everyone's time with the long posts, but just trying to be helpful. I know that my suggestion to not have a main CB in the sub panel was brought up in earlier posts and then disregarded. But I don't believe it is a requirement to have a main circuit breaker, just a "disconnect means"... which could be a circuit breaker but can also be just a switch or disconnect or just a $14 un-fused AC disconnect. Again, I think a main circuit breaker panel is one way to have a disconnect means, but is not required.

I also think that you may be meeting the code with the individual branch circuit breakers in the panel I recommended without a main breaker or even a main disconnect. NEC code in the states allows up to 6 separate disconnect switches (circuit breakers) instead of a single disconnect means. That is under article 225 Part II. This means that as long as you keep the individual branch circuit breakers in the panel to 6 or less, that panel is all you need.

I can not fully research CEC, but did find section 14-418 that shows the need for a "disconnecting means"...(does not have to be a circuit breaker). and section 4(subrule 3) states "two or more ... needs to be grouped together" this indicates that multiple disconnects (circuit breakers) may be used instead of one, but I could not find a specific number. I don't want to provide misinformation, so please let me know if I am mis-stating or mis-using the code, but I don't think the requirement that there has to be a main circuit breaker in a remote subpanel is true.

 

[PJB12]

just wanted to add more supporting info to my above post. The reason I believe a main circuit breaker in a sub panel is not needed is because you are coming from a branch circuit from your main panel to accomplish this requirement. I don't believe you need another one in the remote subpanel. If you came off the top of the main panel from the main leads, then you do need a main circuit breaker...but you are not doing that. I attached a pic to show what I am suggesting (only not 60 amps)

Also, PJB2 made a good point with coating the aluminum wires. Definitely do this even if the lugs say they are safe for AL. I use NOALOX.

Industrial and residential rules work differently in so many ways that it's sometimes hard to stay straight, Gary. Many things that you and I can do, residential disallows.
( I'm an industrial & distribution system electrician in the U.S.. Residential and commercial jobs are only either "friends-and-family" or "I'm out of town for months on a project and bored" jobs. Note that I haven't maintained my Canadian licensing since I left my old employer, so rules may have changed.)

Canadian electrical code and Ontario Electrical Safety Codes will both require a main disconnect (not necessarily over-current, as Gary mentioned) inside this original poster's garage. It can be ahead of the panel (in on on the garage) or in the garage panel, if retained.

The most common & most economical way to do this with a remote sub panel is to put the feeders into the lugs of a circuit breaker and use a breaker retainer, thus making it the Main Disconnect for the building. (If a bolt-on breaker, no retainer is needed.) Alternatively, put a disconnect (or pull-out if allowed) ahead of the load center in the garage.
In either case, you must label it as the main disconnect and label what is the source.


Quote From Post Above: "If you came off the top of the main panel from the main leads, then you do need a main circuit breaker..."

I explain poorly, so a 5 minute sketch is attached to explain what my words below will fail to do well.

The conductors to the garage have to be over-current and short-circuit protected at the source.
Codes won't let the poster come off of the main leads or bus in the source panel to go to the remotely located garage unless those conductors are over-current protected with an adequately sized over-current protective device.

If I remember correctly, Ontario Hydro won't allow homeowner access to the service entrance termination, so the installer would have to come off of lugs on the bus bars downstream of the main disconnecting means- if there are any.

If coming off of the main bus or lugs, the conductors will have to be sized for whatever is the main service's over-current protection. Example: If the over-current for the main panel is 200 amps, the conductors to the garage have to meet requirements for 200 amp protection. If one installs a 40 amp breaker in the source panel, then the conductors only have to meet 40 amp requirements.

Paul

 

[PJB12]

NEC code in the states allows up to 6 separate disconnect switches (circuit breakers) instead of a single disconnect means. That is under article 225 Part II.

That vanished from NFPA 70 (NEC) 230.71 in 2020 for services. All inspectors with whom I've worked since, apply it to sub panels in separate structures as well. (225.30 & 225.31 are cited) Grey area, to be sure!

 

[garygnew]

Industrial and residential rules work differently in so many ways that it's sometimes hard to stay straight, Gary. Many things that you and I can do, residential disallows.
( I'm an industrial & distribution system electrician in the U.S.. Residential and commercial jobs are only either "friends-and-family" or "I'm out of town for months on a project and bored" jobs. Note that I haven't maintained my Canadian licensing since I left my old employer, so rules may have changed.)

Canadian electrical code and Ontario Electrical Safety Codes will both require a main disconnect inside this original poster's garage. It can be ahead of the panel (in on on the garage) or in the garage panel, if retained.

The most common & most economical way to do this with a remote sub panel is to put the feeders into the lugs of a circuit breaker and use a breaker retainer, thus making it the Main Disconnect for the building. (If a bolt-on breaker, no retainer is needed.) Alternatively, put a fused disconnect (or fused pull-out if allowed) ahead of the load center in the garage.
In either case, you must label it as the main disconnect and label what is the source.


Quote From Post Above: "If you came off the top of the main panel from the main leads, then you do need a main circuit breaker..."

I explain poorly, so a 5 minute sketch is attached to explain what my words below will fail to do well.

The conductors to the garage have to be over-current and short-circuit protected at the source.
Codes won't let the poster come off of the main leads or bus in the source panel to go to the remotely located garage unless those conductors are over-current protected with an adequately sized over-current protective device.

If I remember correctly, Ontario Hydro won't allow homeowner access to the service entrance termination, so the installer would have to come off of lugs on the bus bars downstream of the main disconnecting means- if there are any.

If coming off of the main bus or lugs, the conductors will have to be sized for whatever is the main service's over-current protection. Example: If the over-current for the main panel is 200 amps, the conductors to the garage have to meet requirements for 200 amp protection. If one installs a 40 amp breaker in the source panel, then the conductors only have to meet 40 amp requirements.

Paul

Thank you for the response, and I actually think we are not too far off on our ideas. As far as the feed off the top of the main panel, I in no way was suggesting to do this, but just using that as a differential that we are not doing that here... which would have caused a lot of additional issues which you pointed out. I probably shouldn't have even mentioned it. (However; I actually did that when I built my house, but I had a 400 amp feed to my meter, then split off to (2) 200 amp panels upstream of the main breakers. The inspector approved it with proper labeling. But you're right that this has no relevance in this discussion.)

I tend to over-explain and not very well some times, so the TLDR version of the points I wanted to make are:
1-please don't use a 60 amp panel because people assume a 60 amp panel can use 60 amps, and that could cause problems down the road.
2-You could probably use 50 amp protection with the wires, which is closer to what you want.
3- "Disconnect means" does not have to be a circuit breaker unless that is specifically spelled out. If a single point disconnect is required, then the attached pic would work upstream of the panel as an option.
4-You MAY not need a single point disconnect, and multiple branch circuit breakers MAY satisfy requirements.

I do have to concede, however, that the "backfeed" breaker is acceptable and it is just my opinion that it is not preferred. I believe it to be a little non-conventional and can be confusing....but as long as it is labeled correctly it is safe. Plus getting specific tie down parts for that may be difficult.

Overall, this topic peaked my interest and am curious how it turns out. I am also curious if the Ontario code does specifically require a main circuit breaker only. I tried to look at Ontario code online and you have to be in Ontario to view it for free. Thank you again Paul for the feedback

 

[PJB12]

(However; I actually did that when I built my house, but I had a 400 amp feed to my meter, then split off to (2) 200 amp panels upstream of the main breakers. The inspector approved it with proper labeling. But you're right that this has no relevance in this discussion.)

Staying Off Topic, But:
In industrial it's natural to split in the CT cabinet so, being an industrial electrician, I did as you did in my house (essentially the same thing as splitting in the CT cabinet). I wanted motor loads in one panelboard and general use lighting and appliance in a separate load center.

The over-current protection devices (one for each center) are adjacent and proper labeling was in place. But...
Goodness was it ever difficult to get the AHJ and his boss to understand the code references allowing it! And, this was years before the 2020 NEC revision.

I suppose with the removal of the "six throws" rule in 2020, many inspectors would no longer allow this for new typical residential installations- unless one can explain one of the 4 exceptions in 230.7(B). Were I the inspector, your installation would easily satisfy exception #2, Gary.

Paul
PS: I'm a big fan of the current 230.7(B)'s Exception 3 which allows only one service disconnecting means per vertical section of a switchboard (with barriers required between).

Over the decades, I've been to too many tragic explosions where several service disconnecting means were in the same section. (Often done as a means for avoiding the high cost or future inconvenience of GFPE for installations such as 1,000 amp 277/480 volt wye installations.)

I also have seen too many injured or killed because the six service disconnects were scattered through 8, ten or more ganged switchboard sections, not necessarily at the top- nor even just one in each section. A semi trained maintenance worker wanting to swap or service a bus plug would turn off the top and believe that the subsequent bus plugs (and the bus bars) were de-energized.

 

[DonD]

just wanted to add more supporting info to my above post. The reason I believe a main circuit breaker in a sub panel is not needed is because you are coming from a branch circuit from your main panel to accomplish this requirement. I don't believe you need another one in the remote subpanel. If you came off the top of the main panel from the main leads, then you do need a main circuit breaker...but you are not doing that. I attached a pic to show what I am suggesting (only not 60 amps)

Also, PJB2 made a good point with coating the aluminum wires. Definitely do this even if the lugs say they are safe for AL. I use NOALOX.

Gary: thank you for all your valuable information.
I think you’re right about the confusion regarding using a 60 amp main breaker in the garage panel. I’ll forget that idea.
In Canada, we need do a main breaker in a stand alone garage panel. I found that out when I ran power to my outside sauna building.
i think my best solution is to use backfed 40 amp breaker with the proper retaining clip.