Bond location for pole mounted service disconnects

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Clodbuster

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I'm doing an upgrade to a wellpit and am having trouble finding code references (2014) for where the main bond can occur. I would like to do it at the main lug panel in the pit and use the well casing for the grounding electrode, as it will be the easiest and most effective electrode.

The existing system complicates things as it has 2 fused disconnects in series before the (new) main lug panel. The first is immediately after the meter, but is on an intermediate pole 75+ feet from the pit. The second is at a replacement pole about 20 ft from the pit, where the power goes underground and enters the pit via PVC conduit and then the main lug panel. See the sketch below:

Wellpit configuration.jpg

Can I make the bond at the main lug panel? And then just run an EGC from the service disconnect (2nd disco) back to it to provide ground continuity?

Secondly, are there any code requirements for grounding electrodes at the first disco?
 
You have to establish a neutral bond connection at or before the first disco and a GES.

You will need 4 wire conductors from there on.

A second GES could be established at panel in well pit but not another neutral bond, the GEC would connect to the ground bar and the neutral would float.

250.24(A)(1) and (A)(5)
 
I just noticed your other thread that I had replied to.

Is this the same project? If so and a disco is getting moved or removed, the answers are going get muddled.

I want to merge the two, okay?
 
jumper said:
You have to establish a neutral bond connection at or before the first disco and a GES.

You will need 4 wire conductors from there on.
Click to expand...

This is what I am hoping to avoid - the 4 wire conductors at least, as they will add a lot to the cost here. I planned to delete the drops to the first disco altogether as it serves no real purpose, but then noticed that the meter was there. Not sure how feasible to get them to move it as haven't called yet.

I'd rather delete the first disco to avoid the 4-wire, but is there a way that the first disconnect could be recategorized as a isolation means per 547.9 or similar? As this is a system serving livestock watering and fence charging only.

jumper said:
the GEC would connect to the ground bar and the neutral would float.
Click to expand...

By float, I understand this to mean that the neutral and ground bars need to be kept separate as per any regular subpanel install?
 
jumper said:
I just noticed your other thread that I had replied to.

Is this the same project? If so and a disco is getting moved or removed, the answers are going get muddled.

I want to merge the two, okay?
Click to expand...

It is the same project. The other post was asked before noticing the meter there so is no longer relevant. Probably simplest to close/delete it it that's ok. Thanks.
 
Clodbuster said:
By float, I understand this to mean that the neutral and ground bars need to be kept separate as per any regular subpanel install?
Click to expand...

Yes and neutral is not rebonded to EGC and enclosure.

I gotta think about the other stuff you just mentioned before I can reply with any accuracy, scernario changed a bit.

Lotsa smart guys here, so hopefully they will chime in also.
 
If your service disconnect is on the pole then the conductors to the pit are feeder conductors and not service conductors. You will need an EGC run to the pit. You still need a grounding electrode system at the pole as well as one for the pit, so drive a rod(s) at the pole and connect to well casing at the pit, connect it to the EGC and leave the neutral unbonded beyond the service disconnect which is at the pole.

Disconnect at the first pole - gets a little complicated and how local AHJ's may call that can vary as well especially if POCO provides or maintains that disconnect. But if it gets designated as the service disconnect then the second pole becomes feeder supplied and needs an EGC. There are exceptions for existing feeders that you possibly can take advantage of - if this was existing.

Nothing wrong NEC wise to just have meter at the first pole and service disconnect at the second pole though.
 
Clodbuster said:
..Can I make the bond at the main lug panel?
View attachment 19009
Click to expand...

Excellent illustration that shows how Inside Wiremen do it underground, and Linemen go overhead.

Why bother with underground raceways, unless other loads need feeding before pump house?

PoCo might "Meter Spot" first disconnect & new Meter at the pump house, with overhead service dropped directly on pump-house structure.

The replacement pole may also be unnecessary, since 100+ foot service drops are not uncommon.
 
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ramsy said:
Excellent illustration that shows how Inside Wiremen do it underground, and Linemen go overhead.

Why bother with underground raceways, unless other loads need feeding before pump house?

PoCo might "Meter Spot" first disconnect & new Meter at the pump house, with overhead service dropped directly on pump-house structure.
Click to expand...
"pump house" is a pit - needs to go underground at some point before entering. Overhead wiring most of the way does cost less, but is not so easy if you don't have right equipment to install it either.

A lot of area utilities have both overhead and underground wiring anymore. Overhead wiring on secondary is becoming a thing of the past to some extent around here. On farms machinery is just too large anymore to have to constantly think about overhead wiring.
 
kwired said:
..A lot of area utilities have both overhead and underground wiring anymore..
Click to expand...

Either way, if PoCo Spots Meter at a pit riser or a lateral, the Op's goal is accomplished (Main bonding at pit Main Breaker).

Eliminating the replacement pole with 100ft service drop is just icing on the cake.
 
ramsy said:
Why bother with underground raceways, unless other loads need feeding before pump house?

PoCo might "Meter Spot" first disconnect & new Meter at the pump house, with overhead service dropped directly on pump-house structure.

The replacement pole may also be unnecessary, since 100+ foot service drops are not uncommon.
Click to expand...



The replacement pole is very necessary - you can see the original is only about 12 feet tall, all of that out of the ground as it is sistered to a railroad tie. The tie rotted off, so the whole works is held up by some weeder chain wrapped around a fencepost stub hammered into the ground. You can easily reach up and touch the bottom two bare OH wires. Good farm stuff :lol:
Poles1.jpg

The new pole (right behind it) will get the OH wire up to 18 ft to meet 230.24(B) for grazing ground, and there will also be large farm equipment in here periodically that needs to clear. You're right in that it could all go underground, but this is a rocky canyon bottom and there's a dry wash intercepting where the ditch run would be. That and I am trying to utilize as much of the existing OH wiring as possible to watch cost.

The pump pit structure only comes about 10" out of the ground, it's all pit and a roof, so no mounting anything to the side.

I think moving the meter would be one good option and will look into that next week.
 
kwired said:
If your service disconnect is on the pole then the conductors to the pit are feeder conductors and not service conductors. You will need an EGC run to the pit. You still need a grounding electrode system at the pole as well as one for the pit, so drive a rod(s) at the pole and connect to well casing at the pit, connect it to the EGC and leave the neutral unbonded beyond the service disconnect which is at the pole.

Disconnect at the first pole - gets a little complicated and how local AHJ's may call that can vary as well especially if POCO provides or maintains that disconnect. But if it gets designated as the service disconnect then the second pole becomes feeder supplied and needs an EGC. There are exceptions for existing feeders that you possibly can take advantage of - if this was existing.

Nothing wrong NEC wise to just have meter at the first pole and service disconnect at the second pole though.
Click to expand...

Having the service disconnect at the second (replacement) pole and bonding there would be a good outcome and that's what I'm going to shoot for I think. I'll call the REA next week to sort out if that first disconnect is theirs or ours. If they are maintaining it, it is pretty tired and they may be willing to move meter anyhow.

The second disconnect is so worn out I can't tell if it was ever SE rated or not, but it needs replaced as well along with the pole it's on. But both disconnects and the pole configuration shown in the original sketch are all existing, and I'm not changing configurations of any of the poles or disconnects - just replacing and making taller. Curious what feeder exceptions you are referring to on this as that could be very helpful?
meter1.jpg
 
Clodbuster said:
View attachment 19011
..trying to utilize as much of the existing OH wiring as possible to watch cost.
Click to expand...

Nice photo of hills. I see wires stop near replacement pole.

Without another tall pole & overhead lines at pump pit, Table 300.5 Column 2 allows a shallow trench thru the rocks, with 4-wires in RMC. If that wont go 6" down, it should be concrete encased. Tbl 300.5, Note 5
 
If everything is 240 do you need a neutral?
 
Clodbuster said:
Curious what feeder exceptions you are referring to on this as that could be very helpful?
Click to expand...

When that was initially installed (probably at least 70 years ago, that was when you did still see individual hard drawn copper overhead conductors like you have) we were allowed to ground the neutral at separate structures similar to how we do services. This has not been allowed since 2005(?) NEC, but is still exception to allow existing installations that were once compliant to remain as is.

See 250.32(B).
 
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