Good morning everyone, I’ve been getting an influx of service upgrades recently and in the past, I’ve always updated the range & dryer wires to being 4 wire. I’d make the service disconnect outside, move all the bonding and grounding to the outside enclosure, resulting in the inside panel being a sub panel. I’m in Massachusetts which means they did away with 250.140 (B) (5) being an option for the dryer & range bonding. Sometimes updating the wires are easy, sometimes they can be a headache. With that said, I was curious if anyone else had an efficient setup allowing the existing 3 wires to remain in place, example what type of listed emergency disconnect (not service disconnect) are you using? The plan would be using a standard meter, running SEU to an emergency disconnect, then continuing into the house panel with SEU, and doing all the bonding & grounding in the panel inside, adding the correct labels on disconnects and panels, and making it complaint. I just wasn’t sure the best enclosures people have found or setups have worked best for them in the past. I know milbanks are only listed for use as service equipment only. Model numbers are appreciated! (Sorry, I’m more on an industrial guy and want to be more fluent and efficient on the residential side of things) Cheers!
Meter / Main setup
- Thread starter ZachHane
- Start date
cadpoint
Senior Member
- Location
- Durham, NC
Most power company's list equipment manufacturers on their websites. I really am fond of Sq D but there are several enclosures and
panel builders here in NC. Hamilton and Eaton respectfully come to mind.
panel builders here in NC. Hamilton and Eaton respectfully come to mind.
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
Does a piece of equipment that is "only for use as service equipment" NOT allow it to be used as the emergency disconnect? 
I sorta see t conflict but it shouldn't matter in practice.
I sorta see t conflict but it shouldn't matter in practice.They do have a list on the websites for all the approved meters but as far as the disconnect side of things, they don’t care or list what is preferred as they mostly just care what meter is installed, AHJ determines what they like or don’t like for the disconnect side of things which leaves a gray area
I couldn’t agree more. I know Milbank changed their listing to “Service disconnect only”, meaning you can’t relabel it to “Emergency Disconnect, Not Service Equipment” because somehow it voids the listing… I’ve also heard of guys failing for using a meter to disconnect and the disconnect only being listed for service equipment as well, having to change the disconnect to a listed emergency disconnect, then running the 3 wire inside to do all the bonding & grounding in thereDoes a piece of equipment that is "only for use as service equipment" NOT allow it to be used as the emergency disconnect?
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
Under the 2023 NEC, unfortunately yes. The conflict is purely linguistic, electrically SOUSE would be fine.
But I guess this is a short lived issue, as in the 2026 NEC First Draft emergency disconnects are going away and single family residences (and two family?) will be required to have an exterior service disconnect.
Cheers, Wayne
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
Can you provide some documentation on this? The ones I get come with a sticker for each, FWIW ....
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Such units have a grounded conductor bus that is permanently connected to the frame. As long as they don't have anything leaving that is otherwise considered to be a branch circuit or feeder I see no reason they can't be considered the emergency disconnect and have one to six service disconnects on the inside of the building supplied by it.Does a piece of equipment that is "only for use as service equipment" NOT allow it to be used as the emergency disconnect?
I would discourage using the units with meter/main and 8 branch breaker spaces for this as it makes it too easy to add a non compliant branch circuit or feeder to the mix, but at same time kind of sort of is compliant as long as none of those breaker spaces are used.
Interesting.
I still don't get why they want this, but maybe makes more sense with what was common occurrences in other places. They actually amended out the emergency disconnect rules when we adopted 2023 here. We never adopted 2020 so it was a non issue until adopting 2023.
As for actual documentation, I don’t have that, other than he said she said. But I believe the main issue that’s been ran into is that the listing on the equipment is “suitable ONLY for use as service equipment”. I know the previous enclosures came with both stickers, but I believe now they are starting to only come with “Emergency Disconnect, Service Disconnect” which at the point I believe you have to bond within that service equipment, not allowing you to use an “Emergency Disconnect, Not Service Disconnect” sticker which would allow an SEU into the main panel and bonding there. The issue lies within the service equipment rating, I believe the neutral must be isolated from the ground which I don’t think is the case or option.
With that said, I could be way off which is why I’m here. Usually I upgrade the service, do all my bonding and grounding outside, run 4 conductors inside and separate everything. Resulting in me biting the bullet and upgrading the dryer & range outlets, not having problems with that..
I’m looking for an alternate option when rewiring range and dryer isn’t feasible or worth the headache. I know more money is made, but sometimes I like to get in and get out and provide the customer multiple options depending on their budget.
Which milbanks have you been using that have been still coming with both stickers? And what is the verbiage on the stickers?
Thanks!
- Location
- Tennessee NEC:2017
- Occupation
- Semi-Retired Electrician
I know of nothing stating you have to run a new 4-wire to ranges and dryers if you have to disturb wall finishes to do so. If the grounded conductor is insulated, it can come from any panel. If the grounded conductor is uninsulated, then it can only come from the main panel. A work around for that was given us, here, to use. We are allowed to tape the bare grounded conductor white and still come from a subpanel.
Are you referring to exceptions 250.140 (4) & (5)? I only ask because in Massachusetts they did away with exception 5, taping the conductor. Exception 4 would comply if I use a meter to disconnect then feed into the house with SEU, bond & ground into panel, making the inside panel a main panel, therefor not needing to run a new wire. The problem lies if I were to do my bonding & grounding outside in a meter main combo, and run an SER inside, making the panel a sub panel, it’d result in me having to update that circuit since I can’t use exception (5). (I believe), like I said, residential is on the less familiar side to me
Jaybone812
Senior Member
- Location
- Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
The Eaton meter mains are not restricted to be used as service equipment only . We use them for that reason so we have the ability to use it as the service disconnect/emency disconnect or emergency only .
Sorry I don’t have a part #at the moment but I’m in mass as well and we get them from CES
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That’s awesome and reassuring! I’ll have to check them out, thanks for the info!
Jaybone812
Senior Member
- Location
- Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
No problem. 90% of the dwelling unit service upgrades we do are done so the service disconnect is the main breaker panel in the basement . That way we don’t even have to think about satisfying 250.140
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Jaybone812
Senior Member
- Location
- Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
You’re correct about 250.140(b) in the mass electrical code. Mass deleted 250.140(b) #5 , so 250.140(b) only consists of (1-4) in our state electrical code
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TX+ MASTER#4544
Senior Member
- Location
- Texas
- Occupation
- electrical Code instructor and mentor
2023 NEC Texas
You said ...being an option.....see below. (B) (5) allowing the existing to remain, per your question?
250.140 (A) or (B) 1 thru 5... Frames of Ranges and Clothes Dryers
For Emergency Disconnects 230.82 (1)
For dwellings 230.85 (A) (1) (2) (3) (B) (1)(2)(3) for one and two family dwellings.
For use on the supply side see 230.82(1)-(11).
For marking see 230.85 (D) Identification....(E)(1) (2)(3)
Note: Article 338 SE Cable Types -SE and USE
Thanks for reading
Comments accepted
TX+MASTER#4544
Jaybone812
Senior Member
- Location
- Massachusetts-2023 NEC
- Occupation
- Commercial & Residential Electrician
Massachusetts amended 250.140(b) and deleted #5 so in the mass electrical code 5 is not an option , we need to comply 250.140(b)(1-4)
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hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
The ones I’ve seen have the neutral bonded directly to the can, and do not have a removable jumper, so I think that’s why they are service disconnect only.
shortcircuit2
Senior Member
- Location
- South of Bawstin
UL 231 lists power outlets including meter-mains.
Any metering equipment (meter-mains) with the neutral bus bolted to the cabinet frame must be marked "Suitable ONLY for use as Service Equipment." Those Eaton meter-mains may be missing the marking, but they are listed as Suitable ONLY for use as Service Equipment. This equipment can only be installed per 2023 MEC 230.85(B)(1) and marked EMERGENCY DISCONNECT- SERVICE DISCONNECT per 230.85(E)(1)(1)
Service equipment that is marked "Suitable for Use as Service Equipment" (SUSE) will have a floating neutral buss, An example is a Eaton 200-amp Breaker Disconnect that is SUSE rated and these are permitted to be installed per 230.85(B)(3) and marked EMERGENCY DISCONNECT- NOT SERVICE EQUIPMENT per 230.85(E)(1)(3) and installed as such you can run the 3-wire SEU into a Main Breaker Service Equipment Panel and leave those dangerous 3-wire dryer and range branch circuits.
Example below of a SUSE rated floating neutral service rated disconnect...
Yes for a period of time Milbank was sending both stickers. But, this violated the listing and now that no longer happens.
Why do I say are 3-wire range and dryer branch circuits dangerous? Well generally they are not when qualified persons are involved. But when those unqualified appliance delivery persons are installing the cords at delivery, that can be dangerous and has killed people by electrocution. Now if it were a new 4-wire branch circuit with GFCI, incorrectly installed cords will trip the breaker, no-one gets hurt.
Any metering equipment (meter-mains) with the neutral bus bolted to the cabinet frame must be marked "Suitable ONLY for use as Service Equipment." Those Eaton meter-mains may be missing the marking, but they are listed as Suitable ONLY for use as Service Equipment. This equipment can only be installed per 2023 MEC 230.85(B)(1) and marked EMERGENCY DISCONNECT- SERVICE DISCONNECT per 230.85(E)(1)(1)
Service equipment that is marked "Suitable for Use as Service Equipment" (SUSE) will have a floating neutral buss, An example is a Eaton 200-amp Breaker Disconnect that is SUSE rated and these are permitted to be installed per 230.85(B)(3) and marked EMERGENCY DISCONNECT- NOT SERVICE EQUIPMENT per 230.85(E)(1)(3) and installed as such you can run the 3-wire SEU into a Main Breaker Service Equipment Panel and leave those dangerous 3-wire dryer and range branch circuits.
Example below of a SUSE rated floating neutral service rated disconnect...
Yes for a period of time Milbank was sending both stickers. But, this violated the listing and now that no longer happens.
Why do I say are 3-wire range and dryer branch circuits dangerous? Well generally they are not when qualified persons are involved. But when those unqualified appliance delivery persons are installing the cords at delivery, that can be dangerous and has killed people by electrocution. Now if it were a new 4-wire branch circuit with GFCI, incorrectly installed cords will trip the breaker, no-one gets hurt.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
I don't believe so. Anything on supply side of the service disconnecting means is service equipment. With that is the requirement that non intended current carrying metallic components need to be bonded to the grounded conductor. There is no need for an equipment grounding conductor on the supply side of the service disconnect because of this as the extra conductor simply becomes a parallel path to the grounded conductor.
Equipment that is labeled as suitable only for use as service equipment nearly always has a grounded conductor bus assembly that is not capable of being easily unbonded from the enclosure. Equipment that is labeled suitable for use as service equipment has a bonding screw, strap or other method that is easy to bond or unbond from the enclosure depending on usage needs.
I see no reason something suitable only for use as service equipment can't be the emergency disconnect with and also have the service disconnect further downstream. Both pieces of equipment must be bonded to the grounded service conductor. The only thing that is different about them for bonding purposes is the more recent code requirement for one to be considered the emergency disconnect, along with the code required identification labels. Before 2020 NEC you still could possibly had an unfused switch on outside and essentially wire it up the same way as is now required, but if you put something with overcurrent protection there it likely would been considered to be the service disconnect, therefore an EGC and separation from the grounded conductor required beyond that point. 2020 and 2023 specifically allow this outside disconnect to not be considered the service disconnect as long as the inside unit meets requirements for the service disconnecting means.