200A Electrical Panel with 150A Main Breaker and 150A Feed. Is it Legal?

[sms]

I need a new electrical panel. One electrical contractor looked at the existing feed and said that he could pull 150A wiring through the existing pipe and change the main breaker in the 200A panel to 150A so that the breaker matched the wiring coming in.

Another contractor insists that this is not legal because someone could change that 150A main breaker to 200A in the future because the panel is rated for 200A.

My next door neighbor did this and it passed inspection. But was it a clueless inspector or is it really legal?

[gfretwell]

It is certainly legal. The real answer is right there on the lapel. Each panel will list the different breaker types it will accept. I bet that panel says 100-200.

The code does not address the dumbest thing someone can do after the initial, permitted installation. In fact I wrote a proposal to the 99 code saying the wiring should reflect the largest size overcurrent device (fuses in my case) that would fit in a holder and it was roundly rejected.

My original concern was 400a switch gear with 250 KCMIL copper wire and 250a fuses installed. Everyone I asked, up the chain, said it was legal, hence my proposal to change the code..

[clare]

It is legal and is done all the time. I can only get 150 amp service to my house unless I pay to have the underground wiring updated all the way to the transformer vault. I can put in a 200 amp panel with a 150 amp breaker, and if in the future I need more power I can have the underground updated and swap the main breaker for a 200. It's not like you can just pop out the breaker like a branch circuit breaker, at least not on MOSTservice entrance panels. Most companies don't make (or at least the distributors don't carry) a panel between the 100 and the 200 - they just downgrade a 200 for 125 or 150 amp service.

[sms]

Well apparently my neighbor's installation was never inspected. Two different electricians spotted issues with it instantly, but not related to the 150 amp main breaker on a 200 amp p0anel. It was the improper connection to the incoming power line and improper grounding. This was done by the contractor installing his solar system from Solar City.

I actually did find a 150 amp version of the 200 amp panel they were looking at so hopefully they'll order one of those, SC816D150C rather than the SC816D200C. They would prefer one with the meter on the top but apparently those don't exist anymore for that width in semi-flush.

But it appears that there is no good reason not to use the 200 amp panel with a 150 amp main breaker.

[clare]

We couldn't even think about installing one of those here. Our meter bases have to be separate and outside. And a 200 amp 8 slot 16 circuit panel???? My 100 amp panel has more circuits than that (and it's too small)

[philo]

As long as the wiring and the breaker match, there would be no problem.

OTOH: I'd find how much money it would add to simply replace the feed and go with 200 amp wiring.

[clare]

In my case about $4000 - if everything goes well. So I'll be putting in a 200 amp service panel with a 150 amp breaker and a new meter base to meet Waterloo North's current requirements - and if the underground cable fails it will be Waterloo North Hydro's job to replace it at their cost - and current replacement is 200amp minimum.

If I want it replaced with 200 amp while it is still totally functional, I pay.

[gfretwell]

This is the "meter main"and you will end up with another panel inside with most of your circuits in it, fed as a sub panel. Typically these are installed as upgrades and the existing panel is left in place. They will feed additional sub panels from the meter main for new circuits so they don't need that many in there. Doing it this way, you are only replacing the SE going from the old meter base to the existing panel with SER or simply shoving another conductor in the raceway if it is wire in pipe. You still have to add the ground bus and swing over the ground wires, lifting the bonding jumper but that is a lot less labor than replacing the panel.

[philo]

Yeah, I suppose an underground feed replacement would be expensive.

I was only thinking of "above ground"

[gfretwell]

The thing that might make a service lateral expensive is if they did not put in a big enough raceway. If it is 2" he is fine for 4/0 aluminum (200a). It might be a tough tug but it legally fits. If it is 1.5" you might be digging or using 2/0 copper. Price would determine that.

[TomR]

I am just curious . . , what does the "existing pipe" mean? Is it an overhead service and the existing pipe is the conduit down the side of the house? Or, is the "existing pipe" and underground conduit to the house? Also, what is the size of the "existing pipe"?

Part of why I am curious is that, if it is an overhead drop, maybe changing the conduit/pipe at the same time as the new service line is be installed wouldn't cost much, and maybe the new service could just be 200A for not much more money -- mostly just the additional materials cost.

I noticed that later you discovered that your neighbor didn't end up getting his inspected after all.

In my area, the normal process is for the contractor to pull the permit (which I pay for) and then the contractor does the work and a final inspection is done. That way, I know that the work that is done will meet all of the codes and will have a final approval sticker upon completion.

[clare]

Not 100% sure, but I THINK our underground laterals are direct bury cable.. Like 99% sure. No way to just "pull in" new conductors without digging(or trenchless "directional drilling")

[sms]

Very expensive to do it properly because of the pipe diameter going down from the roof. Unless I let them put the feed on the wall outside.

[sms]

No, this is the panel used in my areas to replace the old 100 amp Zinsco panels. 16 circuits is more than enough for these houses which are not more than about 2000 square feet. There is no sub-panel.

[gfretwell]

How much do you think a couple of sticks of 2" gray PVC costs?

[TomR]

I think that I would probably want to go with the new 200A service and run it down the wall on the outside. But, you are there, and I am here, and you know better what you want and why.

Are you saying that there is an existing conduit/pipe, but that it runs through the roof and then down inside a wall but not on the exterior of the wall outside? If so, I thought that there was some kind of code that prohibits the feed from running more than just a few feet inside a building before a service disconnect switch. But, maybe that doesn't apply if the incoming service line is inside the building but also inside a conduit -- I don't know.

[sms]

It's not the cost of the PVC. But then you already knew that.

[sms]

Yes, the feed is through conduit in the wall.

150 amps is more than enough, and that's what they are doing. A 200 amp feed on the outside of the wall would have also worked.

They are going to do a sub-panel because it is a better installation to have the solar going into a sub-panel. That will leave room for expansion, though there are no more high-current devices that I would be likely to add. If anything, I'd go to a gas range and oven and scrap the electric cook top and electric oven.

They actually said that a 100 amp panel would still be sufficient but that my 100 amp panel (Zinsco) has the usual Zinsco issues.