main breaker on 100amp sub panel, do i need it?

[Stevenanto]

Hi everyone,

I have yet another electrical question. I have bought the subpanel in the link below. I passed a wire from my 200 amp main panel to this new subpanel. I have two different people telling me two different things. One of them says that i dont have to put the 100amp main breaker on the sub panel because i have a 100 amp breaker coming from my main. The second person says I have to put yet another breaker in my subpanel at the top.

which on is right? would it work either way, i dont want it to catch fire. I called the company schneider but they can give me an answer until Monday.

here is a link of the exact panel that i bought.
https://www.rona.ca/en/panel---electrical-panel-0265030--1


thanks in advance

 

[pattenp]

If the subpanel is installed in the same structure as the main panel then the main breaker is not needed in the subpanel. If the subpanel is installed in a detached structure from where the main panel is installed then a main breaker is needed in the subpanel. At least that's how it is in the US.

 

[TRWham]

...If the subpanel is installed in a detached structure from where the main panel is installed then a main breaker is needed in the subpanel. At least that's how it is in the US.

Or if it has 6 or fewer disconnects, then you could skip the main breaker.

 

[wyliesdiesels]

Hi everyone,

I have yet another electrical question. I have bought the subpanel in the link below. I passed a wire from my 200 amp main panel to this new subpanel. I have two different people telling me two different things. One of them says that i dont have to put the 100amp main breaker on the sub panel because i have a 100 amp breaker coming from my main. The second person says I have to put yet another breaker in my subpanel at the top.

which on is right? would it work either way, i dont want it to catch fire. I called the company schneider but they can give me an answer until Monday.

here is a link of the exact panel that i bought.
https://www.rona.ca/en/panel---electrical-panel-0265030--1


thanks in advance

Is the subpanel in an attached or detached structure?

What kind and size of wire did you use?

 

[Aceman]

If the subpanel is installed in a detached structure from where the main panel is installed then a main breaker is needed in the subpanel.

Just a little correction to this.

A separate structure needs a means to disconnect the wiring entering the structure. A main breaker is one option. So is a disconnect switch.

As mentioned above you can also use the 6 disconnect rule rather than one main breaker.

225.39(D) requires a 60 amp rating minimum or combination of, to meet the 60 amp rating.

 

[Norcal]

The OP is in Canada.

 

[Aceman]

The OP is in Canada.

Nice catch.

The OP can disregard everything I just said!!!

 

[Low277]

Rules vary between US and Canada, also rules can vary by areas within the same state. In many instances the Authority Having Jurisdiction can interpret things differently.

Many years ago I had a local inspector that would require a sub panel in same structure have a main breaker if the sub panel had any single pole breakers in it. I forget what his reasoning for it was.

 

[wyliesdiesels]

Nice catch.

The OP can disregard everything I just said!!!

I missed it too.



I cant help ya

 

[pattenp]

The OP is in Canada.

That's why I didn't get down in the weeds.

 

[Norcal]

Nice catch.

The OP can disregard everything I just said!!!

It was the Rona link that got my attention & there were not many replies then either.

 

[sberry]

I don't think it's drastically different. While it may be accurate thay ahi may read it different most of this isn't different state to state,, some minor exceptions. Local amendments are really very few and most originate from ,,,,,,,, "someone told me",, and another from,,, "I was always told".

 

[MattT]

which on is right? would it work either way, i dont want it to catch fire. I called the company schneider but they can give me an answer until Monday.

From an engineering standpoint you don't need a main breaker in the sub panel. The 100A breaker in the main panel will provide overcurrent protection.

If you are forced, or want, to comply with local codes a disconnect may be required and using a main breaker in the sub could be the easiest way to comply with that requirement.

 

[The Cobbler]

if the sub panel is in a detached building, it needs a disconnect. the 100 amp breaker can be used as a disconnect. even if the service to the sub is less than 100 amps.

not sure about the code if panel is in same structure

 

[Stevenanto]

thanks everyone for the help! very informative as always. I will end up getting the breaker. better safe than sorry

 

[mike93lx]

thanks everyone for the help! very informative as always. I will end up getting the breaker. better safe than sorry

for the $40 a 100a breaker costs, I'd put one in too. A lot easier to do it up front than add it later and it's nice to be able to easily shut down a panel for work.

 

[Falcon67]

Without regard to codes, I find it good to have a main in a big sub panel - it's handy to be able to shut down the whole panel if needed.

 

[sberry]

That s part of the reasoning behind no main in some of the subs, it actually does shut the whole panel down when you turn off the feed breaker.

 

[mike93lx]

That s part of the reasoning behind no main in some of the subs, it actually does shut the whole panel down when you turn off the feed breaker.

Of course it does, but why go into two panels if you can just go into one?

 

[sberry]

Because 1 doesn't shut the power off to that panel. There are live lugs above the main.

 

[wyliesdiesels]

Because 1 doesn't shut the power off to that panel. There are live lugs above the main.

That really depends on the panel and how its made

many panels have the feeder ungrounded conductors going straight to the main so there is no live lugs with the breaker off other than the ones on the line side of the breaker.

 

[mike93lx]

Because 1 doesn't shut the power off to that panel. There are live lugs above the main.

i dunno, of all the times I've killed a main to work in a panel, the lugs at the top weren't my concern, it was the buss bars and breaker connections around where I was working. sure an extra measure of safety isn't bad, but is it really needed?

There is always power upstream at some point, whether at another panel, the lugs, meter socket, pole...

 

[Stevenanto]

for the $40 a 100a breaker costs, I'd put one in too. A lot easier to do it up front than add it later and it's nice to be able to easily shut down a panel for work.

the cost of this one is about 90-100$ in my area, everything is much cheaper in the US lol. thats not the point, I will be putting it in regardless of the cost, better safe than sorry.

 

[sberry]

i dunno, of all the times I've killed a main to work in a panel, the lugs at the top weren't my concern,

The code writers do not care what "your concern" is. They do this from decades of forensics, they have a good reason for what they do and the way it is.