Question on replacing garage subpanel

[lmg]

Hello. I have a home built in 1988 with a Square D QO40M200RB Series G1 sub panel in the attached garage, which is fed with a 200 amp main panel on the outside of the house via 1/0 XHHW copper cable and a 125 amp breaker from the main panel. The sub panel has room for only 1 additional full-size breaker, and I do not want to use the miniatures.

Both panels serve both the living space and the garage. Future improvements may include arc fault breakers on all locations required by 2023 NEC, just because I think this is good insurance, not necessarily for code compliance, but I understand that they may be required as a result of the panel upgrade.

Both panels also have the Square D QO2175SB QO SurgeBreaker, Surge Protection Device, 22.5kA, 120/240V, 1-Phase installed. I mention model number here because these just recently became available for the older QO panels, just in case someone else has been looking for these.

I would like to replace the panel in the garage with a larger panel so I have room for additional circuits for future expansion which may include adding a 220-volt air compressor, and possible mini split installation at this panel.

My plan is to move the sub panel breaker to the new garage panel, and use a 200 amp panel but with a breaker rated at 150 amps, and I want the plug on neutral feature. I want the newer style panel so that I do not have compatibility issues like I experienced not being able to find the whole house surge protection noted above. Also, the 200-amp panels have more choices for more breaker spaces.

Additional information: the main panel is buried in rigid foam insulation board and stucco covering any available knockouts, so making any changes to this panel would require possible cutting and patching of the stucco and insulation.

What, if any additional upgrades will the 2023 NEC require? When I have this work quoted, I just want information to sort out different stories from different bidders on what may be required to comply.

Thank you in advance for your responses.

 

[sparky 1971]

It depends on where you are and any local amendments that have been made. I can change a panel in one jurisdiction where changing the panel doesn't require anything else. I can then go across the street two another jurisdiction and be there for two weeks doing all of the required extras that go along with a simple panel change. Then I can go to another place and be forced to install the worthless AFCI "protection" as well as GFCI's and smoke detectors even if they are battery powered. Bottom line is find out what the AHJ requires.

 

[lmg]

Thank you for your reply Sparky 1971.

AHJ was going to implement the 2023 NEC, but we are still using the 2020 NEC here, and the AHJ always publishes their exceptions to NEC, so I know they have not changed anything related to my project. I am interested in what the 2023 NEC would require for my project and the justifications for the changes.

None of the local electrical contractors are going to be familiar with 2023 unless they sat on the committee which delayed implementation here. I used to work with contractors, and the AHJ on code issues, so I know how the process is handled here. Code officials here are in my opinion, overly accommodating to special interest groups, and often ignore the justifications which cause updates to NEC, and the international building codes.

And I am very interested in AFCI, as I have had a push in wired receptacle which suddenly went dead, so I believe the potential of additional issues exists here. Probably need to just replace all the receptacles, but that would be expensive, so thinking of getting a 15 and 20 amp AFCI breaker and using them as diagnostic tools.

I bought this house about 2 years ago, and did have an electrician who also happens to be a licensed electrical engineer look at both panels, and he fixed some obvious issues in the garage. However he has since retired and has no interest in further work.

 

[mike93lx]

You won't hear any support here for afci and if you put them in, you'll likely spend a lot of time and money chasing issues.
If you already had a bad receptacle, just replace them, especially if they are backatabs. A commercial grade TR receptacle is about 3 bucks. Even in a big house with 60-100 receptacles, it's pretty short money to fix what could be a major problem

 

[sparky 1971]

The 2023 will require you to have an exterior disconnect and a surge suppressor, which it sounds like you already have. As far as AFCI being required, that's the AHJ's call. If a circuit is modified or extended it is supposed to get an AFCI so it depends on whether they think changing panel is modifying the circuit or not. There is one jurisdiction I do occasional work in that seems to think so, other cities or areas say no.

And you can change a whole bunch of receptacles for the price of one AFCI breaker if you DIY it

As far as the justification, it's almost always money.

 

[dscheidt]

You won't hear any support here for afci and if you put them in, you'll likely spend a lot of time and money chasing issues.
If you already had a bad receptacle, just replace them, especially if they are backatabs. A commercial grade TR receptacle is about 3 bucks. Even in a big house with 60-100 receptacles, it's pretty short money to fix what could be a major problem

this forum is also full of people that say "Get rid of your GFCI so the appliance that's actively trying to kill you can have a better chance at it!". So the prevailing opinion about safety devices is a little suspect. AFCI has greatly improved, and most of the things that set them off are actual wiring faults (especially when retrofitting them. Lots of boxes with all the neutrals tied together, and stuff like that.).


OP: if your sub is fed by breaker in the main panel, there's no need to change the main breaker in a replacement panel. As long as it's less than or equal to the rating of the breaker feeding it, it is only a disconnect, over current protection is from the breaker in the main. The other alternative is to add a second subpanel in the garage, fed by the first.

 

[lmg]

You won't hear any support here for afci and if you put them in, you'll likely spend a lot of time and money chasing issues.
If you already had a bad receptacle, just replace them, especially if they are backatabs. A commercial grade TR receptacle is about 3 bucks. Even in a big house with 60-100 receptacles, it's pretty short money to fix what could be a major problem

Thanks Mike. I have read enough of the electrical related threads here to realize that afci is not at all appreciated by electricians. Part of my interest is that I just want to experience new technology, and my interests are very diverse.

 

[lmg]

this forum is also full of people that say "Get rid of your GFCI so the appliance that's actively trying to kill you can have a better chance at it!". So the prevailing opinion about safety devices is a little suspect. AFCI has greatly improved, and most of the things that set them off are actual wiring faults (especially when retrofitting them. Lots of boxes with all the neutrals tied together, and stuff like that.).


OP: if your sub is fed by breaker in the main panel, there's no need to change the main breaker in a replacement panel. As long as it's less than or equal to the rating of the breaker feeding it, it is only a disconnect, over current protection is from the breaker in the main. The other alternative is to add a second subpanel in the garage, fed by the first.

Thank you dscheidt, but the existing sub panel has a main breaker, and I find it handy, so I want to keep one on any new panel.

The existing panel is on a very small wall constructed as part of an insulated enclosure for the well tank, so I really do not have anywhere an additional panel could be easily installed.

 

[lmg]

And you can change a whole bunch of receptacles for the price of one AFCI breaker if you DIY it

Thank you sparky 1971, I am 75 and starting to feel it. I find that my time has become incredibly valuable. As much as I have enjoyed such tasks in the past, I find that time spent elsewhere is time better spent.

 

[mike93lx]

Thanks Mike. I have read enough of the electrical related threads here to realize that afci is not at all appreciated by electricians. Part of my interest is that I just want to experience new technology, and my interests are very diverse.

I hear you.

I still think you should replace any backstabbed outlet and not expect an afci to give you the proper protection

 

[bronc076]

I hear you.

I still think you should replace any backstabbed outlet and not expect an afci to give you the proper protection

THIS! Instead of relying on a safety device to detect faults, remove the potential for faults! A properly wired house should never trip a breaker. Now the **** we plug in that breaks, burns up, catches on fire, falls into the sink, etc. That stuff will but the home wiring should not unless the drywallers and trim guys shoot screws and nails into the wiring.

 

[sparky 1971]

Thank you sparky 1971, I am 75 and starting to feel it. I find that my time has become incredibly valuable. As much as I have enjoyed such tasks in the past, I find that time spent elsewhere is time better spent.

You could hire someone to change the receptacles for the price of a few AFCI's and eliminate a point that is going to fail eventually. If a backstabbed receptacle causes the breaker to trip, you still have a backstabbed receptacle that needs repaired or replaced.

 

[dave*99]

Given the choice between eliminating a well known problem such as backstabbed devices vs adding the sometimes problematic and always expensive AFCI breakers..... Let me think.......

And finally the third option.... Install the AFCI's and every time another one trips you can then replace all the backstabbed devices on that circuit because you won't know which device caused the trip.

Decisions Decisions Decisions...

 

[larry4406]

Back stabbing is like using Matchlight charcoal for grilling.

Just say no.

I wish they would eliminate the back stab option on all devices.

 

[dave*99]

Back stabbing is like using Matchlight charcoal for grilling.

Just say no.

I wish they would eliminate the back stab option on all devices.

Either can lead to a fire.

 

[Norcal]

Back stabbing is like using Matchlight charcoal for grilling.

Just say no.

I wish they would eliminate the back stab option on all devices.

Just use 12 AWG minimum and your wish is granted.

 

[Kezorm]

Thanks Mike. I have read enough of the electrical related threads here to realize that afci is not at all appreciated by electricians. Part of my interest is that I just want to experience new technology, and my interests are very diverse.

For what it’s worth, I’m three years in with Eaton CH PON AFCI+GFCI breakers on most every 15A and 20A circuit in the house. Never had one trip. I certainly don’t like the price of them and maybe question the need (AFCI portion), but I haven’t had a single issue to date.

I’m definitely in agreement with everyone on the receptacles. Priority before anything else would be eliminate any cheap backstabbed receptacles.

 

[acer66]

You won't hear any support here for afci and if you put them in, you'll likely spend a lot of time and money chasing issues.
If you already had a bad receptacle, just replace them, especially if they are backatabs. A commercial grade TR receptacle is about 3 bucks. Even in a big house with 60-100 receptacles, it's pretty short money to fix what could be a major problem

I might be the exception of the rule because my house has a myriad of Eaton BR, yes I said it Eaton BR, AFCI breakers since 2015.

The only problem I had so far was using a welder on an AFCI breaker otherwise all I got was crickets.

Having said that I do not know if they do any good nor do I like that they are warm which means they use or more waste energy.

 

[mm08822]

Just use 12 AWG minimum and your wish is granted.

Unless of course someone has NOS of #12/14 version of backstabs:

 

[American Locomotive]

Here's the thing: AFCI breakers are unreliable. I don't mean in that they fail often, or nuisance trip. I mean that they're unreliable for keeping you safe. They're basically useless. The first generations of AFCIs were probably useful, but they nuisance tripped on everything. Turn a light switch on a little too slowly? Trip. Turn your vacuum cleaner on? Trip. Fire up a walkie-talkie next to your breaker panel? They would all trip.

The latest AFCIs no longer nuisance trip, but they have calibrated them so they only trip if they see a very specific type of waveform, and it has to be a continuous arc for a certain duration. Sporadic or intermittent arcs will not cause a trip.

https://www.tiktok.com/video/7288374556442496286

Don't waste your time or money installing AFCIs. They're just "safety theater". Replace problematic outlets with the high end ones with the clamp terminals, and have true peace of mind.

 

[lmg]

OK, thank you everyone who responded, especially those who responded since last Friday while I was camping in the woods and turkey hunting. Don't worry, no turkeys were harmed in any way. The 15th was last legal day, and I think that I was just too late to hear any gobblers.

So you have convinced me to just get all the backstabbed breakers replaced. House was built in 1988, and most look like they are original judging from how easy it is to plug anything in to them.

About the AFCI, I will probably get one and move it around every week or so, and see if anything shows up. Sounds like a good time to map all the receptacles to their respective breakers as well.

Ordered the 2023 NFPA 70 this morning. So if I have any more questions, I will not be bothering you guys again on this unless I come up with definite code questions.

Thank you all again for your great, and caring responses. This is quite a great community.

 

[mike93lx]

Going in and out of a panel every week to move a breaker around sounds like a great way to damage something or get hurt.

 

[lmg]

Going in and out of a panel every week to move a breaker around sounds like a great way to damage something or get hurt.

Thanks, but that is why I like to have a main breaker in my subpanel.

 

[mike93lx]

Thanks, but that is why I like to have a main breaker in my subpanel.

Main breakers don't shutoff the feed to the panel.

But it sounds like you have a path you want to take. Good luck