Is this Sub Panel Wired Correctly?

[Preston Davis]

Hi all. New member here with a sub panel question.

Is this sub panel wired correctly?

The feed from the main breaker box comes in from the top left. As you can see, the grounds are connected on the left side and the neutral is on the right, but it appears that both terminal bars are connected with a neutral cross bar (the black connector on the 4th lug down).

If my understanding is correct, I basically have 2 neutral terminal blocks and the grounds and the neutrals are not separated.

The panel is an Eaton BR1224L125 and it is installed next to the main panel.


Thank-you for your advice.



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[Gunnar Alquist]

Hi all. New member here with a sub panel question.
Is this sub panel wired correctly?
The feed from the main breaker box comes in from the top left. As you can see, the grounds are connected on the left side and the neutral is on the right, but it appears that both terminal bars are connected with a neutral cross bar (the black connector on the 4th lug down).
If my understanding is correct, I basically have 2 neutral terminal blocks and the grounds and the neutrals are not separated.
The panel is an Eaton BR1224L125 and it is installed next to the main panel.

Thank-you for your advice.

Hi Preston,

"Main Breaker Box"???
"Main Panel"???

Looking through my NEC information, I don't see any mention of a "main breaker box" or "main panel". Could you possibly mean "service equipment"?

(how am I doing Jerry?)

You are correct, in that the connector bar between the neutral and Equipment Grounding Conductor terminal block should have been removed. Even though the neutral terminal is not being used, the neutral and EGC can only be bonded together in the service equipment.

You don't really have "two neutral blocks" because the EGC terminal block is connected to the panel enclosure. What you basically have is a short circuit between the EGC and neutral conductors. Since there should be no voltage differential between the neutral and EGC, there are no sparks. But, this is potentially unsafe.

[Jerry Peck]

Hi Preston,

"Main Breaker Box"???
"Main Panel"???

Looking through my NEC information, I don't see any mention of a "main breaker box" or "main panel". Could you possibly mean "service equipment"?

(how am I doing Jerry?)

Quite well, Gunnar.

You are correct, in that the connector bar between the neutral and Equipment Grounding Conductor terminal block should have been removed. Even though the neutral terminal is not being used, the neutral and EGC can only be bonded together in the service equipment.

You don't really have "two neutral blocks" because the EGC terminal block is connected to the panel enclosure. What you basically have is a short circuit between the EGC and neutral conductors. Since there should be no voltage differential between the neutral and EGC, there are no sparks. But, this is potentially unsafe.

From the photo, it looks like that crossover bar was not intended to be removed, which leaves two likely options: a) that the label states "Suitable for use as Service Equipment Only"; or to the effect of 'when used as other than Service Equipment, install optional EGC terminal bar model blah-blah-bah at the provided mounting holes located at blah-blah-blah'

You can see the dimpled back mounting areas in the back of the enclosure panel, and this may allow for the use of several of the holes in the back of the panel to have clearance for the grounding bar terminal mounting screws (frequently, there will be dimpled forward holes for this purpose, with the dimpled forward space to allow for the mounting screw to fully penetrate the back of the enclosure without hitting the substrate the panel is mounted to).

Notice that there is a neutral-to-ground bonding strap which was not used, yet they defeated that 'not used' condition by using the other neutral terminal bar for the equipment grounding conductors ... which are now "not grounded" until the path goes to ground through the neutral conductor (which is grounded back at the service equipment).

Another creative way to do things wrong without thinking about what was done wrong or how ... Get-R-Done ... but do it neatly.

Also, the white conductor to that breaker, being part of a cable, should have been re-identified as 'red'.

Notice that the red feeder conductor bus feeds the breaker with the black conductor, so the black and white conductor should be switched, and the white (now re-identified to red) would be on the red.

[Gunnar Alquist]

You don't really have "two neutral blocks" because the EGC terminal block is connected to the panel enclosure. What you basically have is a short circuit between the EGC and neutral conductors. Since there should be no voltage differential between the neutral and EGC, there are no sparks. But, this is potentially unsafe.

Oops! i wasn't paying close enough attention to the photo (good thing Jerry was here too). You DO have two neutral blocks, of a sort. The EGCs should be connected to a terminal block that is bonded to the enclosure.

But the neutral and EGC are connected together via that crossover bar, which they should not be.

From the photo, it looks like that crossover bar was not intended to be removed...

HA!

I say you're wrong Jerry! Give me a sawzall, a hammer, and a little pry bar and I could get that crossover bar out!

(oh, you said "intended")

[Jerry Peck]

(oh, you said "intended")

Reading IS fundamental (so the saying goes).

[Jim Robinson]

If they pop out the connection to the cross over bar on the right and put the bonding strap into the terminal bar, it should be correct. And of course, change the ground wires over to that side. I see there actually are no neutrals on the right side bar. It may be easier to remove the connection on the left side and just move the bonding strap over to that side.

[Jim Port]

Both of those are neutral bars. A ground bar should be added to the enclosure and the grounds moved it it.

[Preston Davis]

First and foremost, thank you for the responses, and forgive my amateur terminology. I should have said "Service Entrance" and "Feeder Panelboard".

What is so very frustrating is that 2 electricians and 1 county inspector has been inside of this box, and never said a word.

That neutral crossbar can, and now has been removed. It was held in place by the lugs only.

If my understanding is correct, the left terminal block (which has the ground wires connected) needs to be bonded to the sub panel now, as it is attached with the plastic 'standoffs'.

Again, thank-you all for the replies.

[Jerry Peck]

That neutral crossbar can, and now has been removed. It was held in place by the lugs only.

Just because something "can" be removed does not mean it is intended to be removed or should be removed. That is now no longer as it was listed, it has been modified/altered, which creates new issues.

This is what should have been done:

Both of those are neutral bars. A ground bar should be added to the enclosure and the grounds moved it it.

Then this:

If my understanding is correct, the left terminal block (which has the ground wires connected) needs to be bonded to the sub panel now, as it is attached with the plastic 'standoffs'.

Would also have addressed been addressed ... instead of creating a new issue.

If you have a cord and plug connected appliance, you "can" cut the plug off the cord and permanently wire the cord to a junction box... but you have modified/altered the appliance and it is no longer "listed" due to those unauthorized modifications.

[david shapiro]

Reading IS fundamental (so the saying goes).

Basic reading skills were debatably acquired by applying one's fundament to the classroom seat. With remote learning, . . .??? I suspect even more variable results now correlated with SES.

[david shapiro]

I suspect that by far the greatest danger at that panelboard was the lack of cabinet grounding.

Some serious safety wonks--Jim Dollard for one--have proposed something related regarding the gradual elimination of permission to return a stove or dryer circuit on a concentric ground, as service panels are converted to subpanels. They say yes, while there is no record of shock incidents due to the WWII era permission, it is out of place. On the other hand, there isconsiderable detriment to requiring installers upgrading such services, putting in new, appropriately located panels and converting the old ones to subpanels and having this mean running new stove circuits. So permit the anomaly to continue in place, while forbidding other downstream neutral-ground connections. This will let a whole bunch of older homes to get safer panels legally.

The issue is always how much voltage people might be exposed to, due to potential difference between the local ground and a surface they might touch. IFF a service panel is adjacent to a downstream panel, that should be minimal. Should. With the downstream panel's enclosure grounded only by any grounding conductors haphazardly brushing against its surfaces, I would be nervous. True, if my memory's right BRs may be galvanized rather than painted, so at least there wouldn't be a barrier of powder-coat, but . . . if they were neat but ignorant, did they torque connections? At both ends? Or at least know what they should feel like?

In my house, the service panel is connected to the adjacent downstream panel via an RMC elbow. Yes, the neutral bar floats, but no, I don't have grounding conductors attached to a separate terminal bar in that, either. It's perfectly legal, too. (I ran all its circuits in ACHH.)

[Jerry Peck]

They say yes, while there is no record of shock incidents ...

Define "shock incidents".

Shock as in similar to static discharge after walking across carpet in the winter?

Or shock as in "emergency room visit" or "call 911"?

If the latter, then I've never been "shocked", not even by a near direct hit lightening strike while lying on a cast iron drain pipe while under a house on rain soaked ground feeding wire up from the crawlspace.


If as in the first, I and many others have had that from ranges and dryers, even refrigerators plugged into adapters plugged into ungrounded 2-prong receptacles.

Heck, I (and from photos on this board, many others too) have found service equipment panels changed into non-service equipment panels without having an insulated neutral installed (gosh, shucks, that means replacing the service entrance conductors with feeder conductors ... that's not going to be easy ... maybe no one will know if I skip that ... (probably not for years, anyway, and I'll be long gone by then).

[david shapiro]

Define "shock incidents".

Shock as in similar to static discharge after walking across carpet in the winter?

Or shock as in "emergency room visit" or "call 911"?

Jerry, those were a lot of distractors, or what a logician might term the phallacy of irrelevance. (I hope my orthography's not overly irreverent.)

To Code Making Panels, records of shock incidents that pose danger to life, health and property are what counts. Formal documentation. Their classic challenge is "Show us the bodies."

So shock from walking across carpet or stroking a puddytat is a will-o-the-wisp, unless you're talking about a location with flammable vapors that the spark could ignite.

But what if there are bodies? People have been not just shocked but, at the least, injured by using systems with bootlegged grounds or faked ones. However, nobody's suggesting accepting downstream grounding willy-nilly.

The examples of general downstream grounding or nongrounding too are not applicable to the question of whether there is enough voltage drop to pose shock hazard when panelboards are side-by-side even when not joined by a wireway. These examples too are not applicable to the question of whether there is enough voltage drop to pose shock hazard when panelboards are served by feeders that used to be service conductors, sized to carry 60 amps or sometimes more. True, so sized under the 83% rule, which should not be applicable if the new service panel serves further distribution. The resolution of this issue demands discussion and data.

I'm not saying the meliorators have the right of it. I do, however, challenge the relevance to that discourse of the examples you cited.

[Jerry Peck]

I do, however, challenge the relevance to that discourse of the examples you cited.

David, the relevance of my examples is that may people (fellow inspectors) I know have been "shocked" (i.e., my reference to the static shock of walking across a carpet or your refer to Sylvester the puddytat as the "shock" involved) when touching the appliances I mentioned.

My other example was that there are many much more serious "shocks" which never get reported.

Those were in response to where I knew you were coming from (they want bodies) versus the reality of the real world of what actually happens (no bodies that I am aware of for touching those appliances).

[david shapiro]

I'm a little confused by part of your comments, Jerry.

I've gotten electrostatic shocks betimes as i touched grounded surfaces after trudging on rugs. That suggests but certainly doesn't guarantee that they're the surfaces of safe equipment.

As for there being more serious shocks than are reported, even presuming that documents are filed correctly so much of our injury and fire experience doesn't get near the reporting systems--NFIRS and hospitals.

I've been thinking of volunteering for our local VFD just to take on the reporting, and maybe some CRR.

We both have experienced frustration with the processes that go into codes and standards. At the same time, I wouldn't want standards to be more easily created or changed by people saying, "Look, I don't have documentation of how commonly this happens, but I've experienced X, which is related to some degree to what I'm talking about."

That was all abstract, but I think saying all downstream grounding should be treated as equally dangerous would be rule-change by assertion. Absence of evidence is not evidence of absence, yes, but we'll see what data they do come up with.

[Jerry Peck]

I'm not referring to walking across carpet and touching the appliances; I'm explaining the severity (lack thereof) as being essentially similar to walking across carpet and touching ground (like when I walk through the downstairs hall and reach for the light switch to turn the light off ... but I touch the grounded cover plate screw before the switch ... and nor only hear, but feel, that POP!

Touching the appliances and getting a similar shock, well, it is still a shock.

An unreported shock, but still a shock.

The appliances set the voltage sniffer off, and measure voltage to ground (I don't recall the voltages measured, only that they varied and where measurable).

Ground the appliances out for testing and the voltage (thus the shock) is no longer present.

[david shapiro]

An unreported shock, but still a shock.

The appliances set the voltage sniffer off, and measure voltage to ground (I don't recall the voltages measured, only that they varied and where measurable).

Ground the appliances out for testing and the voltage (thus the shock) is no longer present.

Sounds as though you're referring to ungrounded outlets such as the fridge in the earlier example; bringing essentially an equipment grounding conductor (egc) from the panel to the outlet. Agreed.

It's interesting that with pools, you must bond a motor to the equipotential grid unless it's double-insulated, while you must bond the interior metal chassis to the egc in either case. It makes sense, and it also underscores the purpose of the grid not being as a circuit grounding connection.

Sorry; squirrel hole.

So how would you document how common is the experience of a nongrounded outlet shocking people, Jerry?

And would such substantiation serve well to substantiate the need to forbid any further use of the grounded conductor as an egc downstream of the main bonding jumper, beyond the proscription of its use on branch circuits??

[Jerry Peck]

So how would you document how common is the experience of a nongrounded outlet shocking people, Jerry?

And would such substantiation serve well to substantiate the need to forbid any further use of the grounded conductor as an egc downstream of the main bonding jumper, beyond the proscription of its use on branch circuits??

Both are good questions.

Neither has easy answers.

[david shapiro]

Both are good questions.

Neither has easy answers.

Jerry, we seem to be on the same page. (I'm reading מימין לשמאל )

I don't see documenting violations of the present downstream-grounding rules for outlets on general branch circuits as necessarily bearing on the issue of stoves and dryers being fed from subpanels via cables without separate grounding and grounded conductor.s.

However, data demonstrating the frequency or urgency of cases where people are shocked by non-grounded or bootleg-grounded outlets could support one desideratum. I would like to eliminate the permission to replace a 2-wire receptacle with like. Instead, where rewiring is not chosen, I want the requirement to default to GFCI protection.

I did see that old data on defective GFCIs. My hope is that this is much rarer with the auto-monitoring requirement. If UL943 can nudge the EOL behavior options further in the direction of "stops providing electricity" I'll be a happy pup. We're moving slowly in that direction.

[Jim Port]

I would need to look, but I remember inspectors asking if a range was now being fed from a non-service panel while doing upgrades in the 90s.

[david shapiro]

I would need to look, but I remember inspectors asking if a range was now being fed from a non-service panel while doing upgrades in the 90s.

Interesting, Jim. Am I right in thinking that you refer to ranges fed in SE cable with two insulated conductors?
Are you referring to HIs or AHJs?
And were they asking "is this house miswired" or "Do you know if the rule changed?"

[Jim Port]

AHJs regarding SE cables feeding equipment from a non service panel. I have not looked in the code book.

[david shapiro]

AHJs regarding SE cables feeding equipment from a non service panel. I have not looked in the code book.

250.142(b) is Use of Grounded Circuit Conductor for Grounding Load-Side Equipment. 250.140 is Frames of Ranges and Clothes Dryers.

In the mid-1980s the corresponding language was in 250-60 and 250-61(B); ditto in the mid-1960s for 250-60. Go back to 1953, it's Section 2560.

The requirement that the cable originate at the service equipment (if the neutral were uninsulated) was added in the 1968 edition. Before then, service panel, subpanel, the origin didn't matter, so long as it was at least 10AWG.

[Jerry Peck]

250.142(b) is Use of Grounded Circuit Conductor for Grounding Load-Side Equipment. 250.140 is Frames of Ranges and Clothes Dryers.

In the mid-1980s the corresponding language was in 250-60 and 250-61(B); ditto in the mid-1960s for 250-60. Go back to 1953, it's Section 2560.

The requirement that the cable originate at the service equipment (if the neutral were uninsulated) was added in the 1968 edition. Before then, service panel, subpanel, the origin didn't matter, so long as it was at least 10AWG.

Grounding of electrical appliances found ib:

2560 in 1947 also.

2560 in 1946 also ... oh, wait there was no 1946 ... except that I have an Analysis of 1946 Revisions and a 1946 Handbook (which states Adopted as 1947 Code).

4237 in 1940.

4235 in 1935.

1606 in 1931.

1606 also refers to and 9 in 1931 (couldn't find much specific about appliances other than the shirt general statement in 1609).

So I didn't go back any further.

[david shapiro]

Grounding of electrical appliances found ib:

So I didn't go back any further.

Go far enough back, and we were disputing whether grounding even one circuit conductor was a good idea. And then it took a while to agree that the grounded conductor generally should not be fused.

I have to agree with Mark Hilbert, who submitted a PC on this, that if we're encouraging the installation of a firefighter disconnect that is not considered the mains/service disconnect, bonding it to the grounded service conductor, and then again running a main bonding jumper in the service panel, commingling grounded an grounding conductors in two or even more adjacent panels indoors, one of which is a transfer switch and the other/s technically subpanels, or one of which is the service panel and the other overflow, seems no biggy. I don't believe in run-on sentences, though.

[Jerry Peck]

Why would an exterior (which is where I would presume to find a "firefighter disconnect" NOT be considered the main service disconnect?

As that would presumably also be the first, it would be the main service disconnect.

An exterior main service disconnect is common in Florida.

If one lives in areas of the country where an interior 'main' disconnect is desired, that is already allowed (I've referred to those as "panel mains" for as long as I can remember.

The difference being that the conductors feeding the interior panel mains would be feeder conductors, not service entrance conductors, and would increase safety by having an overcurrent protection device on the supply side of those conductors instead on on the load side (which allows overloading of the conductors and fires upstream of the first overcurrent protection device).

[Jim Port]

The emergency disconnect does not need to have overcurrent protection. That would leave the house panel as the service.

[Jerry Peck]

The emergency disconnect does not need to have overcurrent protection. That would leave the house panel as the service.

I have not seen any of those.

Would those be located "on" the already burning structure?

Or would those be located a given distance from the burning structure so firefighters can have safe access to those emergency disconnects?

Smart meter already allow the electric power utility to remotely disconnect power at the meter, why not require those instead?

If the reason is a delay in reaching the utility, then have a feature added to them which would allow emergency units such as firefighters to remotely activate that disconnect?

That would save a lot of expense and code changes.

[Jim Port]

It would just be a knife disconnect, similar to an equipment service disconnect.

[Jerry Peck]

But if smart meters are already being used and available, why not just use their built-in disconnecting ability?

[Jerry Peck]

And would those emergency disconnects be enclosed in a secure Knox Box type enclosure to ensure (reduce) the intentional turning off of power by random people doing it 'just because'?

[david shapiro]

The new section (230.87 if I remember right while being too lazy to look) wants it outside but does not require it to be here or there. Surely a VFD has some cloud and could request a local amendment or even a covenant specifying location.

I don't know whether the knox box company or their presumed competitors manufacture service-rated disconnects, a characteristic that is required of these emergency disconnects even when they are not designated as the service switches. It is perfectly acceptable to padlock an outside disconnect. firefighters can cut padlocks, or be given keys.

Why not rely on smart meters? If I were a firefighter, I would feel a whole lot more secure relying on a handle I can pull than on someone remote saying "Alexa, kill power to #324 Woodland." "No, I didn't say 2 to 4 Wood Lane; 324 Woodland." "Siri, can you talk sense to Alexa?"

Anyway, we are allowed to bond this disconnect to the service neutral. It can be mounted to the house, touching aluminum siding. All power leaving it should be going directly to the service panel inside, so it shouldn't add a different kind of risk than does our bonding the meter can to the service neutral. I posit, and submitted a PC suggesting, that a similar situation applies if another enclosure downstream of the service disconnect has neutral and ground combined, so long as it is the first distribution panel.

Am I cooking with gas, here? (It's less polluting than a coal stove.)

[Jim Port]

Apparently natural gas isn't clean enough. NYC want to ban natural gas for heating and cooking. I am sure the grid can support all those heat pumps on cold 10 degree days.

[Jerry Peck]

It is perfectly acceptable to padlock an outside disconnect. firefighters can cut padlocks, or be given keys.

A padlocked cover is easy to get into, even if the lock itself is not cut, the mounting holes for the lock shackle would need to be recessed such as to be inaccessible ... yet not slow or interfere with an emergency shut off by a firefighter wearing gloves.

[david shapiro]

Apparently natural gas isn't clean enough. NYC want to ban natural gas for heating and cooking. I am sure the grid can support all those heat pumps on cold 10 degree days.

That's a good question. The answer, I daresay, lies in grandfathering. Most cooking and heating in NYC will be used in existing installations for some time. As the shift from progresses, the infrastructure will be changing as well.

At one point, Jim, as you know, we didn't have electrical cables and raceways running through homes. We started pulling insulated conductors through gas pipes, including gas pipes that still were running gas.

Other steps will come, and I strongly suspect that "renewable" or "green" natural gas will not prevent the shift to electric heat-producing appliances. Some big questions include how much toxicity and other hazard is associated with storage technologies, both acutely and lifecycle end-to-end, and how vulnerable our electrical utilities remain. However, i don't see data suggesting that gas delivery is necessarily less vulnerable. There are some greedy barstids out there, and whether they're after ransomware or political hegemony, they put people at risk.

[david shapiro]

A padlocked cover is easy to get into, even if the lock itself is not cut, the mounting holes for the lock shackle would need to be recessed such as to be inaccessible ... yet not slow or interfere with an emergency shut off by a firefighter wearing gloves.

Jerry, I don't disagree with the desiderata you name, but I will argue practicalities. A padlocked cover is easy to get into, but so is a meterbase. My understanding of the reason for 230.87 or whatever is that it attempts to reduce the risk created by a firefighter breaking into a locked meterbase (yes, i know they are given keys), cutting an energized service conductor, or taking similar risks. Homeowners can reduce the risk of pranksters killing their power by padlocking; they can't eliminate the risk that committed malefactors will attack their property by doing so.

I do believe that someone who feels that threatened but is not wealthy enough to hire 24 hour guards could arrange for some kind of armored service equipment, with means arranged for firefighter access. Most folks? A padlock, if that. Or if there's been vandalism, add security lights and cameras.

[Dirk Jeanis]

I have not seen any of those.

Would those be located "on" the already burning structure?

Haven't been here in a while. Hi Jerry! Sorry I am a little late to this party.

I have a friend in Carson NV who built a Butler building detached garage (large). He was a public works inspector in Sunnyvale CA before retirement so he knew the ropes. In fact he had been an inspector for Carson as well!

Bottom line is that Carson approved prints and the entire foundation poured, building up and water tight. On rough in of electrical red tag was given for not having a disconnect at the exterior near corner of the garage. The house had an exterior panel at the house facing the driveway to the garage. It had a main dc in that panel, which also serviced the detached garage.

They required him to have a disconnect on the exterior of that garage at the near corner as you approach for fire response personnel, PERIOD. This meant that a wall penetration had to be made instead of conduit through the foundation. It also meant that the conduit layed was rerouted and needed blocked off through the foundation. Believe me, after the time spent in design to water tight, insulate and even weather tight openable doors this was a serious issue for him. No one wants and unnecessary penetration through any building!

So once again this becomes about interpretation vs actual intent. There was already a disconnect method that could be accessed before arriving at the garage, but not good enough to the interpretation! Your idea of accessing the digital shut off of the meter would not work with Carson City at this site! They wanted it on the actual detached building!

I never opened the disconnect box when I visited, however I noted that instead of being mounted at accessible height, it was placed something like 18-24 inches off the ground. Meaning that the fireman must KNEEL to access it. Sometimes it seems that common sense is truly uncommon.

[Jerry Peck]

\Your idea of accessing the digital shut off of the meter would not work with Carson City at this site! They wanted it on the actual detached building!

Dirk, what if ...

What if there was a separate meter on the garage as some people do (so they can monitor the garage or other outbuilding versus the difference to the primary meter - if that was a smart meter, and if it was on the garage, would it have been acceptable?

A lot of "ifs" in there.

I never opened the disconnect box when I visited, however I noted that instead of being mounted at accessible height, it was placed something like 18-24 inches off the ground. Meaning that the fireman must KNEEL to access it. Sometimes it seems that common sense is truly uncommon.

Maybe that was the owners smart a$$ reply to the building department for their interpretation?

I.e., "You demand a separate disconnect on the outside of my garage? You'll get your dang disconnect, but you will have to work to use it!" The owner may have been .

[david shapiro]

Section 225.32 specifies where an auxiliary building's disconnect needs to be located. It is a judgment call, but would be quite a stretch, to call a disconnect located across a driveway as "inside or outside of the building or structure served" and "readily accessible . . . nearest the point of entrance."

We have to keep in mind that "accessible" and "readily accessible" are terms of art, so the dictionary definition is not used in the rule. Both have been specialized terms since the first NEC that defined such terms, the 1920 or 1923.

The AHJ could have rejected the low position, but this would have been a stretch. He or she more likely would have had to cite 110.12 rather than 225.32, given those definitions.

[Jerry Peck]

t is a judgment call, but would be quite a stretch, to call a disconnect located across a driveway as "inside or outside of the building or structure served" and "readily accessible . . . nearest the point of entrance."

I'd have to read the code wording again, but does it say "on the outside of thebuilding" or "or outside of the building"?

Just showing what it implies versus what it says (while ignoring decades of precedents).

[david shapiro]

I'd have to read the code wording again, but does it say "on the outside of thebuilding" or "or outside of the building"?
.

Not "on"; that would make it a slam-dunk. Section 90.4 says that as casuistic as our inclinations might be, the AHJ has to accept our idea of "nearest." The text in 225.32, earlier part of 225.8, comes from 230.70, the reference for this disconnect until the 1993 NEC.

Not knowing the situation, by which I mean not seeing the 1-line, I wonder why the fix wasn't to add a disconnect on the inside, nearest the point of entrance. I can see various possible answers, but requiring that it be located on the outside sounds like local amendment--or invented code.

[Jerry Peck]

... sounds like ... invented code.

That happens all too often.

I'd say more often reducing the codes (no one complains about this for some reason) than inventing something more restrictive (which everyone complains about for obvious reasons).

[david shapiro]

If the reduction is based on, "I know the reason behind that rule, and the danger it was put in to prevent isn't present in this context," cool. If it's based on, "All I was trained to do is plug in this idiot-light tester and look for two ground rods," the polity (our neighbors) must have said, via the building department, "Find a recommended contractor and cross your fingers; the building department's job is to cite buildings with trash visible in the yard. The front yard."

[Rollie Meyers]

But if smart meters are already being used and available, why not just use their built-in disconnecting ability?

From what I have read Smart Meters do not always have remote disconnecting provisions, it's up to the PoCo if they want it.

[david shapiro]

The smart meters I'm familiar with are under the control of the utility. This means that it would be a stretch to consider them to comply with the emergency disconnect requirement in 230.87.

If they are sub-meters, it would be a hell of a stretch to argue they comply with the requirement for a disconnect outside or inside of a separate building fed by an outside feeder or branch circuit in Article 225.

BTW, since I mentioned it earlier in this thread, the effort to require GFCIs to stop conveying electricity when they fail self-test did not achieve consensus. We hung, 14 to 14. In consequence, if you don't manually test a GFCI, it could fail self-test and signal or not; but it fail self-test and either cease to provide power or else fail self-test and refuse to reset next time you push the TEST button. It's up to the manufacturer.

[Jerry Peck]

The smart meters I'm familiar with are under the control of the utility. This means that it would be a stretch to consider them to comply with the emergency disconnect requirement in 230.87.

That was why I said that First Responders would have their own access to the meters to shut the power off. Those emergency disconnects are for First Responders, not for owners, correct?

[david shapiro]

Short answer: keerect.
Long answer: that's the rationale given . . .

Committee Statement:

This revision recognizes the need for an outdoor disconnect for first responders. These requirements are practical, feasible and provide installers with multiple options. Today, first responders and utility personnel do not have a way to safely remove power from a structure unless there is a means to disconnect the electric utility supply that is located outside of said structure in a readily accessible location.

Response Message:

FR-8462-NFPA 70-2018

Practically, it's for first responders, homeowners, people doing repairs downstream, and if you're too trusting, pranksters/vandals.

[Jerry Peck]

Practically, it's for first responders, homeowners, people doing repairs downstream, and if you're too trusting, pranksters/vandals.

If it is also for "homeowners, people doing repairs downstream", then it should be treated as THE ... First ... disconnect, and thus the service disconnect (as those are not "emergency" shut off conditions which would apply to "emergency shut offs/disconnects".

Sounds to me like someone had a good idea, and others have turned it into a way to "bypass the first disconnect" rule to allow anyone to disconnect the electrical service for any reason and thar first disconnect does not need to meet the requirements that service Disconnects ate required to meet.

If that is the case, all they need to do is specify that the service disconnect/equipment be located on the exterior of the structure.

As simple as that.

Want an interior disconnect for severe weather conditions? Feed a secondary main disconnect inside from the main service equipment disconnect (that's already allowed be code - no code changes necessary for that).

Just one more reason to be glad I'm retired and watching this mess from that perspective.

[david shapiro]

If it is also for "homeowners, people doing repairs downstream", then it should be treated as THE ... First ... disconnect, and thus the service disconnect (as those are not "emergency" shut off conditions which would apply to "emergency shut offs/disconnects".
Sounds to me like someone had a good idea, and others have turned it into a way to "bypass the first disconnect" rule to allow anyone to disconnect the electrical service for any reason and thar first disconnect does not need to meet the requirements that service Disconnects ate required to meet.

If that is the case, all they need to do is specify that the service disconnect/equipment be located on the exterior of the structure.

Happily, it DOES have to be service-rated, and follows the rules that apply to a service disconnect in other ways.

There was indeed a debate about whether to require the service disconnect to be outside, so all interior wiring was downstream of the service. NOPE!

Why not? Consider a house with a service upgrade. the existing service panel feeds a stove or dryer using SE cable with a covered, not insulated, concentric neutral.

If the service upgrade includes a firefighter disconnect upstream of the new, indoor, service panel in the same location as the old, no problem. In fact, safer in the even of that emergency.

If the service upgrade requires moving the service outside, now we have to rerun those circuits. What fun. Or we rewrite that WWII-era permission to now allow that SEC downstream-grounded, to a subpanel. Ain't gonna happen. In fact, a number of serious players--like Jim Dollard, a safety wonk if ever, asked for that for 2023 and got turned down. I submitted a PC tweaking their input to permit this only when said distribution panel serves the entire load; I learned yesterday that even in this form, it got shot down.