Establishing service location

[mnelectric]

(for purposes of this post i am speaking mainly of dwellings) Recently in my area the utilities have been requiring us to set a disconnect directly under the meter socket, with thier intention being to keep people out of the meter sockets when adding onto the service. The problem we have been having as a result is that now we have established the service at the pole, usually several hundred feet from the dwelling. So now we have to run a fourth wire to keep grounds and neutrals isolated, as they are bonded at the pole. So we have typical intallation 200 amp feeders into the panel in the house with a #4 aluminum underground cable as the ground. This doesnt seem like a very good ground fault current path to me, any fault has to run through that #4 aluminum several hundred feet before getting back to the source. Worst of all and my main concern is that we get a lot of gophers, or frost breaking underground conductors. It wouldnt take much to cut off a #4 aluminum, and if that happened there would be no way to clear a fault, and no way to know if it was cut off until someone got hurt or worse. Any ideas on how to remedy this situation? I was thinking maybe a Non fused disconnect under the meter instead? Most power companys have thier own meters with the main disconnect built into them so that wouldnt work, but just a thought, anyone else running into this problem?

 

[Dennis Alwon]

Is there a disconnect at the pole ahead of the meter?

 

[Dennis Alwon]

I am not sure how, in the old installs, you can have the service disconnect in the middle of the house unless there is a slab to run the conduit under. Code states that the disconnect needs to be as near as possible to the point of entry. Maybe I am confused on the 2 installs.

 

[electrofelon]

(for purposes of this post i am speaking mainly of dwellings) Recently in my area the utilities have been requiring us to set a disconnect directly under the meter socket, with thier intention being to keep people out of the meter sockets when adding onto the service. The problem we have been having as a result is that now we have established the service at the pole, usually several hundred feet from the dwelling. So now we have to run a fourth wire to keep grounds and neutrals isolated, as they are bonded at the pole. So we have typical intallation 200 amp feeders into the panel in the house with a #4 aluminum underground cable as the ground. This doesnt seem like a very good ground fault current path to me, any fault has to run through that #4 aluminum several hundred feet before getting back to the source. Worst of all and my main concern is that we get a lot of gophers, or frost breaking underground conductors. It wouldnt take much to cut off a #4 aluminum, and if that happened there would be no way to clear a fault, and no way to know if it was cut off until someone got hurt or worse. Any ideas on how to remedy this situation? I was thinking maybe a Non fused disconnect under the meter instead? Most power companys have thier own meters with the main disconnect built into them so that wouldnt work, but just a thought, anyone else running into this problem?

Several code cycles ago, when you could rebond the neutral between structures, the fact that the neutral is almost always bigger than a EGC in a 4 wire feeder was often cited as a reason that the 4 wire system is not necessarily always safer.

A few other comments: The 250.122 EGC is the minimum size. You may, and should, upsize it if you feel it is necessary. Also you cannot have just a disconnect under the meter as the overcurrent device and the disconnect must be "immediately adjacent thereto" per 230.91. Finally directly burying conductors gives me the creeps. I have seen them fail many times. PVC is real cheap and should allay your concern about the EGC becoming compromised.

 

[John120/240]

. Also you cannot have just a disconnect under the meter as the overcurrent device and the disconnect must be "immediately adjacent thereto" per 230.91.

WHAT ? Adjacent doesn't only mean to the left or right of the meter.

 

[mnelectric]

The main breaker in the panel in the house serves as the disconnect required on the building at point of entry. I suppose I could just pipe them, but bidding is compettetive tough to spend more on the service. I was hoping some unforseen exception or something but who knows.

 

[electrofelon]

WHAT ? Adjacent doesn't only mean to the left or right of the meter.

The op talked about putting a non fused disconnect under the meter. I interpreted this as that he wanted to put the overcurrent protection at the house as some sort of loophole to having a 4 wire feeder. Maybe that is not what he was proposing.

 

[fry6]

to keep people out of the meter sockets when adding onto the service
What?!?! A disconnect on the LOAD side of the meter? Since when does the local utility company require ANY equipment on the load side of any metering device?
I highly question your understanding/explanation of your utility company requirement.
With my utility company(who I work for as a trouble shooter) the only requirement for a disconnect is to have a disconnect on the LINE side of any new 3 phase meter pan. And believe it or now, the reason is because it allows the meter service man to set a new 3P meter in a de-energized meter pan, that is the only reason. The new requirement is about 6 years old.

 

[kwired]

The main breaker in the panel in the house serves as the disconnect required on the building at point of entry. I suppose I could just pipe them, but bidding is compettetive tough to spend more on the service. I was hoping some unforseen exception or something but who knows.

You wanted to increase the EGC size yet want to save on cost of raceway?

Larger EGC - especially aluminum will not protect from gophers. If they gnaw on insulation, and expose conductor it will fail, just will take longer with a larger conductor. We are not necessarily talking years longer, but maybe only days, weeks or months. An EGC will last longer though than the nearby ungrounded conductors which they likely will get them also. Putting conductors in a raceway in rodent prone areas pays for itself generally just the first time a rodent incident was avoided - though you will never really know if one was avoided.

 

[mnelectric]

Believe it or not all of my local utilities require a disconnect at the meter on the load side. Their reasoning is then we do not have to cut their meter seals to add to or unhook the service. I was a larger egc was not my first choice, was looking for a loophole to keep the system bonding jumper in the main panel in the house, that we you can be certain the grounds are bonded to the service neutral, regardless of what happens to the underground

 

[suemarkp]

What I don't understand in this post is why is there so much length from meter to house -- are the meters way detached? Every house I've had, had the meter on the house. In that case, putting a disconnect outside near the meter isn't asking much, and the run to the inside panel should be relatively short and protected.

Also wonder how this changes anything. If you have a 200A utility disconnect, would anyone put a smaller panel inside as a new install? If you need a 320A service upgrade, the 200A disconnect will have to be replaced anyway. Just how large of a disconnect is the utility providing?

 

[mnelectric]

This area is kinda in the woods, utility stays out by the road. Service is usually 200 amp as well as utility disconnect. I just don't like having the system bond so far away from where the load will be.

 

[fisherelectric]

Tell the power company putting the service disconnecting means and overcurrent protection so far away from the house makes it not "readily accessible" from the house, so to comply with code you have to put the disconnect on the house instead of under their meter.

 

[suemarkp]

I think you need one there anyway (detached structure requires a disconnect on it, or very near). The Poco won't mind if you need to install another disconnect at the house too, you can have as many more as you want once theirs is taken care of...

 

[GoldDigger]

I think you need one there anyway (detached structure requires a disconnect on it, or very near). The Poco won't mind if you need to install another disconnect at the house too, you can have as many more as you want once theirs is taken care of...

But do you then have to carry both a neutral and an EGC from one disconnect to the next? Does POCO require the ground/neutral bond to be placed at their disconnect?
1000 feet of conductor is a significant cost factor.

 

[texie]

This area is kinda in the woods, utility stays out by the road. Service is usually 200 amp as well as utility disconnect. I just don't like having the system bond so far away from where the load will be.

What you describe is a very common in many areas. The service point (meter and main disconnect) is is remote from the house. It is a feeder (has EGC) from the service to the house. You then put a disconnect on the house to comply with 225.32. This disconnect can be non fused. You also have to have a GES at the house bonded to the disconnect, but do not bond the neutral as this is a feeder (bonding is done at the service by the street).
You could do this with just the meter at the street with service conductors going to the house and establish the service disconnect at the house and be NEC compliant, but many POCO's don't allow this as they want to be able to disconnect the load at the meter without having to go hunting for the service disconnect.

 

[texie]

But do you then have to carry both a neutral and an EGC from one disconnect to the next? Does POCO require the ground/neutral bond to be placed at their disconnect?
1000 feet of conductor is a significant cost factor.

Yes and yes.

 

[texie]

Tell the power company putting the service disconnecting means and overcurrent protection so far away from the house makes it not "readily accessible" from the house, so to comply with code you have to put the disconnect on the house instead of under their meter.

If you want service from the POCO you have do it by their rules. You just have to adjust your design to be NEC compliant. For example, many POCO's require that service conductors can't enter the building and the service disconnect has to be outside even though this is not an NEC requirement. Some, as in the OP's case, require the service point and main disconnect remote from the building where it is convenient for them. That's life, you just have to design accordingly.

 

[kwired]

What I don't understand in this post is why is there so much length from meter to house -- are the meters way detached? Every house I've had, had the meter on the house. In that case, putting a disconnect outside near the meter isn't asking much, and the run to the inside panel should be relatively short and protected.

Also wonder how this changes anything. If you have a 200A utility disconnect, would anyone put a smaller panel inside as a new install? If you need a 320A service upgrade, the 200A disconnect will have to be replaced anyway. Just how large of a disconnect is the utility providing?

Maybe not so common in cities and towns, happens a lot in rural areas. It is also common to supply multiple buildings or other structures in rural areas all from one common pole. Depending on what is at that pole, each feed is either service conductors or feeder conductors. If you were to supply one building with the service like is typically done in cities, then all the other buildings would be supplied by feeders from that first building anyway, unless you connected each feed to the supply side of service disconnecting means, then they are all service supplied.

This area is kinda in the woods, utility stays out by the road. Service is usually 200 amp as well as utility disconnect. I just don't like having the system bond so far away from where the load will be.

Why? Longer service neutral means more potential voltage drop on that neutral, which means you will have higher chance of voltage to "earth" even on properly installed equipment grounding conductors. I would be more concerned of voltage drop on both grounded and ungrounded conductors more than where the bonding jumper is installed.

Tell the power company putting the service disconnecting means and overcurrent protection so far away from the house makes it not "readily accessible" from the house, so to comply with code you have to put the disconnect on the house instead of under their meter.

The house needs a disconnecting means either way, all that changes is whether art 225 or art 230 applies.

But do you then have to carry both a neutral and an EGC from one disconnect to the next? Does POCO require the ground/neutral bond to be placed at their disconnect?
1000 feet of conductor is a significant cost factor.

POCO does not care if you need three or four conductors when you leave that equipment, their requirements stop there.

 

[mnelectric]

i guess my biggest concern is that if you have the bond at the pole remote of the house, you could potentially lose your ecg underground and not know it, thus the house would not have an effective ground fault current path back to the source. noone would notice the bond was gone until someone got hurt or worse, i suppose the best solution is just to put the underground in pipe to better protect the conductors, or else start a riot at my local power company