Service entrance conductors - grounding conductor

[jap]

That's one way to make it happen.

We generally would do the exact opposite.
We would put the Service Disconnect with the OCPD in first then Feed the Manual Transfer Switch to a MLO Panel.

But,,, to each his own.

Jap.

 

[electrofelon]

In this unusual scenario where the service OCPD is in a separate enclosure immediately adjacent to the service disconnecting means, it is unclear how to label the conductors between the two enclosures. They are not service conductors, as that definition says "The conductors from the service point to the service disconnecting means."

Look at the definition of "service entrance conductors" (either overhead or underground). I believe that fits as it uses "service equipment" and not "service disconnect"

 

[wwhitney]

Look at the definition of "service entrance conductors" (either overhead or underground). I believe that fits as it uses "service equipment" and not "service disconnect"

Good point. So the conductors between the service disconnect and the separately enclosed service OCPD are definitely service entrance conductors, definitely not service conductors, and may or may not be a feeder, depending on how you interpret that definition.

Cheers, Wayne

 

[electrofelon]

Good point. So the conductors between the service disconnect and the separately enclosed service OCPD are definitely service entrance conductors, definitely not service conductors, and may or may not be a feeder, depending on how you interpret that definition.

Cheers, Wayne

The definitions are definitely flawed. It appears that "service entrance conductors" are a portion of "service conductors", but "service conductors" only go to the service disconnect, while "SEC" go to the service equipment.

 

[wwhitney]

The definitions are definitely flawed. It appears that "service entrance conductors" are a portion of "service conductors", but "service conductors" only go to the service disconnect, while "SEC" go to the service equipment.

Whoops, I withdraw post #43, as you point out the SEC definition requires the conductors to be service conductors, so they stop at the service disconnect. Conductors between the service disconnect and the service OCPD are neither service conductors nor SECs.

Cheers, Wayne

 

[LarryFine]

Whoops, I withdraw post #43, as you point out the SEC definition requires the conductors to be service conductors, so they stop at the service disconnect. Conductors between the service disconnect and the service OCPD are neither service conductors nor SECs.

That suggests to me that we really should treat the two enclosures as one somehow.

 

[electrofelon]

Whoops, I withdraw post #43, as you point out the SEC definition requires the conductors to be service conductors, so they stop at the service disconnect. Conductors between the service disconnect and the service OCPD are neither service conductors nor SECs.

Cheers, Wayne

Well its not consistent, so I dont dont see how you can conclude one way or the other. The definition of SEC says "service equipment".

 

[cppoly]

Nice discussion here. Just to recap, do we have definitive answers about a disconnect without OCPD (post #15 , see sketch OPTION 1. Reposted here):

1 & 2) Does this disconnect require a neutral bar bonded to the case (MBJ)?
3) If yes, is this then considered a "service disconnect"?
4) Is a separate grounding conductor (in addition to the neutral) required on the load of this disconnect?

 

[electrofelon]

Nice discussion here. Just to recap, do we have definitive answers about a disconnect without OCPD (post #15 , see sketch OPTION 1. Reposted here):

1 & 2) Does this disconnect require a neutral bar bonded to the case (MBJ)?
3) If yes, is this then considered a "service disconnect"?
4) Is a separate grounding conductor (in addition to the neutral) required on the load of this disconnect?

1&2. Yes
3. Yes, unless it is an emergency disconnect as permitted in the 2020 and 2023 NEC.
4. If it is an emergency disconnect, no. If it is anything else, yes

 

[cppoly]

1&2. Yes
3. Yes, unless it is an emergency disconnect as permitted in the 2020 and 2023 NEC.
4. If it is an emergency disconnect, no. If it is anything else, yes

Thanks!!!

Just for my own knowledge, how is grounding / bonding handled in an emergency disconnect? I'm assuming the case also needs to be bonded to neutral but then wouldn't you need a neutral bar for that and wouldn't this connection be considered a MBJ?

 

[LarryFine]

Just for my own knowledge, how is grounding / bonding handled in an emergency disconnect?

To the neutral, of course, just like any supply-side enclosure.

I'm assuming the case also needs to be bonded to neutral but then wouldn't you need a neutral bar for that and wouldn't this connection be considered a MBJ?

No, because there is no EGC/EGC system yet.

It's bonding the enclosure, like a meter base, but it's not connecting it to an EGC system.

 

[jap]

Interesting discussion for sure.

Thanks,

Jap>

 

[electrofelon]

Note everything on the supply side of the service disconnect is bonded to neutral. It's basically the same thing as a MBJ except it is not called an MBJ. An MBJ is a specific type of "service bonding jumper" that is in the service disconnect.

 

[jap]

Note everything on the supply side of the service disconnect is bonded to neutral. It's basically the same thing as a MBJ except it is not called an MBJ. An MBJ is a specific type of "service bonding jumper" that is in the service disconnect.

So once you bond that case to the Neutral in the first disconnect there is a Grounded Conductor and an EGC from there on regardless of wether or not that disconnect has overcurrent protection or not correct?

Jap>

 

[wwhitney]

Nice discussion here. Just to recap, do we have definitive answers about a disconnect without OCPD

I have a slightly different take from the other answers so far today. Article 230 tells us we must have a "service disconnect". 230.82 tells us what limited set of equipment may be installed on the utility side of the service disconnect, e.g. meters as per 230.82(2).

So the first question is whether the "disconnect without OCPD" is on the list of items in 230.82. If yes, then we can just use the grounded service conductor to bond that enclosure, and then the service conductors proceed to the service disconnect as usual.

If no, then the "disconnect without OCPD" is our service disconnect (or we can still make that choice even if the "disconnect without OCPD" could be one of the items in 230.82). We must install OCPD immediately adjacent to it (230.91). The recent discussion has been on this scenario, the MBJ goes in the service disconnect, and we run an EGC from it to the immediately adjacent OCPD, whose enclosure is bonded to the EGC and not to the grounded conductor.

Now I'm of the opinion that a "meter disconnect" as allowed in 230.82(3) just means a "disconnect at the meter location". So that means we do have the option to label that meter disconnect "METER DISCONNECT / NOT SERVICE EQUIPMENT" as per 230.82(3) and continue the service conductors to the service disconnect(s) at another location.

Cheers, Wayne

P.S. I'm also of the opinion that even if our disconnect at the meter had OCPD, we could still consider it a 230.82(3) meter disconnect and label it accordingly. That could be useful, for example, if we need to use a fused disconnect to get a sufficient SCCR for the disconnect, but we don't really ever want the fuses to blow at that location from an overload, so we fuse it at a higher value than the downstream service OCPD.