barkett519
Member
- Location
- MA
- Occupation
- Journeyman Electrician
Hi All, just to clarify cam I run SEU 3 wire from outdoor meter main to main panel inside with main breaker as long as I mark outside meter main emergency disconnect??? Thank you.
SEU from outdoor meter main
- Thread starter barkett519
- Start date
- Location
- Tennessee NEC:2017
- Occupation
- Semi-Retired Electrician
We are not on the 2020 so the emergency disconnect is not required here. But I would think that since the meter-main is listed suitable for service use only, that you would have to run a 4-wire and treat the inside panel as a sub. This is my opinion only.
Rick 0920
Senior Member
- Location
- Jacksonville, FL
- Occupation
- Electrical Instructor
Once you leave your first means of disconnect, grounded and grounding conductors must be separated. A 4th conductor would be required at the MLO panel.
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
My understanding is that, contrary to all prior experience, 2020 NEC 230.85 allows what the OP proposes.
Cheers, Wayne
Cheers, Wayne
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
An interesting approach. Based on the definition of " service equipment" I think I would have to agree with you. However the code is a bit sloppy here
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
The 2023 NEC added a prohibition on using equipment marked "suitable only for use as service equipment" for an emergency disconnect that is not service equipment. An informational note says 'Equipment marked "Suitable only for use as service equipment" includes the factory marking "Service Disconnect".'
That would seem to literally be the only issue with using equipment marked "suitable only for use as service equipment" as a non-service equipment emergency disconnect. Seems to me that a prohibition on the equipment just because of the marking is way overreaction. Just put the required "EMERGENCY DISCONNECT, NOT SERVICE EQUIPMENT" label over the factory marking of "Service Disconnect."
Obviously not allowed under the 2023 NEC, but at best a gray area under the 2020 NEC.
Cheers, Wayne
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
Interesting, thanks. Yeah seems a bit ridiculous. ITs crazy all the issues the NEC has and they put time and energy into fretting about this sort of thing.....
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
It is crazy that they went and made the requirement for an outdoor disconnect in the first place, seeing as not having it for the last 120 some years has not been an issue of note.
I still want an answer to a question I have asked previously. Where are you going to find an unfused switch rated in excess of 10k SCCR if your available SCC exceeds 10 kA???
I think you would have to use a MCS in such cases.
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
Nothing prohibits you from using a fused switch and labeling it EMERGENCY DISCONNECT, NOT SERVICE EQUIPMENT. The label causes it not to be the service disconnect.
Cheers, Wayne
Knuckle Dragger
Master Electrician Electrical Contractor 01752
- Location
- Marlborough, Massachusetts USA
- Occupation
- Electrical Contractor
Yes
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
What allows you to add ocpd ahead of the service point?
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
230.85. [Or more to the point, what do you think prohibits it?]
How is it any different that a POCO supplied/required cold sequence disconnect ahead of a meter?
Cheers, Wayne
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
I don't think anyone is taking about anything on the utility side of the service point.
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
Only if it is the service disconnect. Not if it is an "emergency disconnect, not service equipment" and the service disconnect is downstream.
Cheers, Wayne
- Location
- Tennessee NEC:2017
- Occupation
- Semi-Retired Electrician
With a permanent bond by the mfg in the meter-main, I don't see how it can not be the service disconnect. In every case before the new emergency disconnect rule, a meter-main was the service disconnect and any panel after that was a subpanel and had to be fed with 4-wires. How does a field supplied label (could be a sharpie I guess) added magically change the fact that you have the bond now in two places?
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
The case of the meter main needs to be bonded to the neutral, just like any other equipment upstream of the service disconnect. So the permanent bond is not a problem. The emergency disconnect gets treated the same way a meter base would be treated.
If there's metallic conduit between the emergency disconnect and the service disconnect, that will present parallel paths for neutral current. Same issue as if there's a metallic conduit between a meter base and a service disconnect.
Use a 3-conductor, non-metallic wiring method between the emergency disconnect and the service disconnect, and there's no parallel path for neutral current. There's still only one N-G bond in the system, in the service disconnect, as there's no EGC or SSBJ between the emergency disconnect and the service disconnect.
Cheers, Wayne
- Location
- Illinois
- Occupation
- retired electrician
The neutral can be bonding to every metal enclosure on the line side of the service disconnect. Even if there was not a factory bond at the meter main assembly used as "emergency disconnect, not service equipment", you would have to provide some type of bond. Sure, you could install a supply side bonding jumper, but why would you when the code permits you to simply bond the neutral to the enclosure.
- Location
- Illinois
- Occupation
- retired electrician
Those are independent rules if the outside disconnect is marked "emergency disconnect, not service equipment". In that case there would be a grouping of emergency equipment and a separate grouping of service disconnects.