Bare Neutral Service Entrance

[helgymatt]

Hi,
I have what seems an unusual situation, and two electricians I've consulted say "I've never seen that before".

An outbuilding put up in the early 90's. They re-used an old 60 amp double pull 4 fuse panel. There is a 3 wire underground service line with two insulated hot aluminum stranded wires and 1 bare solid wire neutral. There is no ground wire and no grounding electrode. The service is not an SEU type wire.

The bare neutral goes out the bottom of the panel down PVC and out the building. Somewhere undergournd three must be a splice because it comes in the main disconnect as three insulated wires. Maybe the utility spliced this when the put in underground transformer...?

Anyway, is this bare underground neutral okay/safe? Was it in compliance at some time?

I plan to upgrade to a new fuse panel and trying to decide if it requires an all new service line.

 

[Megawatt]

Hi,
I have what seems an unusual situation, and two electricians I've consulted say "I've never seen that before".

An outbuilding put up in the early 90's. They re-used an old 60 amp double pull 4 fuse panel. There is a 3 wire underground service line with two insulated hot aluminum stranded wires and 1 bare solid wire neutral. There is no ground wire and no grounding electrode. The service is not an SEU type wire.

The bare neutral goes out the bottom of the panel down PVC and out the building. Somewhere undergournd three must be a splice because it comes in the main disconnect as three insulated wires. Maybe the utility spliced this when the put in underground transformer...?

Anyway, is this bare underground neutral okay/safe? Was it in compliance at some time?

I plan to upgrade to a new fuse panel and trying to decide if it requires an all new service line.

My friend the answer is no on the 3 wires going to the building. You need to pull 4 wires to your building with 2 of them being your hots and 1 neutral and the last wire will be your equipment ground and it will probably be bare. It also needs to be GFCI protected. I would not have to say what you have is safe since in reality the neutral is a current carrying conductor. No the utility company will not make a splice underground and make sure that the wire you get is underground approved. You will need # 6/3 romex with ground

 

[helgymatt]

My friend the answer is no on the 3 wires going to the building. You need to pull 4 wires to your building with 2 of them being your hots and 1 neutral and the last wire will be your equipment ground and it will probably be bare. It also needs to be GFCI protected. I would not have to say what you have is safe since in reality the neutral is a current carrying conductor. No the utility company will not make a splice underground and make sure that the wire you get is underground approved. You will need # 6/3 romex with ground

Regarding 3 wires vs 4. Yes, I understand new work requires 4. This is old work. My house and 3 outbuildings all have three wires. The house was re-wired this way 200 amp service in 2015. Ground rod at the house and ground rod at the main disconnect after the meter. I would have 20k in rewiring all these feeders - one that's 5 years old.

Regarding GFCI protected, can you elaborate? I understand GFCI breakers in a panel for individual circuits. Do you mean something else or different than this?

 

[helgymatt]

My friend the answer is no on the 3 wires going to the building. You need to pull 4 wires to your building with 2 of them being your hots and 1 neutral and the last wire will be your equipment ground and it will probably be bare. It also needs to be GFCI protected. I would not have to say what you have is safe since in reality the neutral is a current carrying conductor. No the utility company will not make a splice underground and make sure that the wire you get is underground approved. You will need # 6/3 romex with ground

Another question. I have a meter -> then a manual transfer switch for auxilary power (with ground electrode there bonded to neutral) -> then 4 different 3 wire underground feeders that go out.

No fuse on that transfer switch. I just ran into a local electrician who says that in this scenario 3 wire is fine because the main disconnects are then considered at each of the 4 fuse panels. Is this correct?

He didn't like the idea of a bare neutral underground, especially since it appears there is a coupler to aluminum somewhere underground and its highly doubtful its waterproofed.

 

[Megawatt]

Regarding 3 wires vs 4. Yes, I understand new work requires 4. This is old work. My house and 3 outbuildings all have three wires. The house was re-wired this way 200 amp service in 2015. Ground rod at the house and ground rod at the main disconnect after the meter. I would have 20k in rewiring all these feeders - one that's 5 years old.

Regarding GFCI protected, can you elaborate? I understand GFCI breakers in a panel for individual circuits. Do you mean something else or different than this?

I’m saying that if you do anything to your buildings you will need to bring them up to today’s standards which is 4 wire. What I mean about GFCI protected is all buildings must be GFCI protected. What ever breaker is feeding each building needs to be on a GFCI breaker. You can leave it the way it is now because years ago what you have was legal but not now. On this forum you will get the answer that you are looking for good or bad. We advise you of today’s standards.

 

[norcal]

That bare aluminum neutral is turning to a toothpaste like substance*, it's best to get it replaced ASAP, the 3-wire feeder may have been allowed then but a bare AL neutral underground is bad news & will need to be upgraded to a 4-wire feeder. BTW, a bare neutral in conduit is not a good thing above ground either.

*It will fail & being proactive and replacing with a proper 4-wire now will save the grief that will happen when failure does occur, turning into that pasty substance also occurs when insulated direct burial aluminum conductors have the insulation damaged.