Underground decisions to make

[rmack898]

New house, new shop on 10 acres and utilities will be underground.

I met with the power company engineer to discuss my needs and where we are going to bring in power. I will have a 200amp service for the house and 200amp to the shop. We decided that I will put in a 400 amp, meter/2circuit panel that will be located between the house and the shop and each building will have its own 200 amp breaker. The run from the pole to the meter base is 215' and I have to put in the pipe. They want 3" pipe, 36" deep with 36" radius ells. All of this pipe run will be through forrest, is there any need for sch.80 pipe or will sch.40 be adequate?

Next question: The run from the meter base to the house is 115' and to the shop is 95'. I have no reference books here in my camper but my gut feeling is telling me that I'm going to need 1Ga copper (I'm not using aluminum) or can I get away with 2 Ga? Can I fit that in 2" pipe or do I need to run 3"?

I will be adding a data pipe while I have an open trench. My thought is 1" pipe from the pole to a j-box at the meter for a co-ax run, and then 1" from the j-box to the house for co-ax and cat5, and 1" from the j-box to the shop for cat5. Am I missing anything? I only want to dig once.

 

[Kaizen]

I'd do several extra pipes for other things not accounted for. Ever going to need air in the house garage or house? i'd put one you can pull an air hose through. pipe is cheap and since you are digging........

 

[alfredeneuman]

Next question: The run from the meter base to the house is 115' and to the shop is 95'. I have no reference books here in my camper but my gut feeling is telling me that I'm going to need 1Ga copper (I'm not using aluminum) or can I get away with 2 Ga? Can I fit that in 2" pipe or do I need to run 3"?

You need 3/0 copper if you have a 200 amp breaker
The ground wire will need to be #6
It's tight, but it could be done with a 2" conduit

 

[rmack898]

You need 3/0 copper if you have a 200 amp breaker
The ground wire will need to be #6

I guess my gut feeling was way off.

 

[Fallon]

Power next to data lines causes interference, especially if ran parallel for any noticable distance. I avoided this by putting fiber in my conduit next to the power conduit rather than copper. Depending on the distances & how close it may or may not end up being an issue. This goes for Ethernet as well as coax cable or phone line & DSL. You obviously have more control over this if you are running Ethernet between buildings than getting a line from the phone or cable company.

The cost of multi-mode fiber isnt actually that much worse that copper Ethernet. But it is a lot more fragile & really can't be terminated by a home user. That means you have to pull it through the conduit with the connectors on. The gear on either end is a a bit more expensive & complex as well.

Sent from my SM-N950U using Tapatalk

 

[mike93lx]

I guess my gut feeling was way off.

So will your bank account.

Why is aluminum ok for the power company but not you?

 

[rmack898]

So will your bank account.

Why is aluminum ok for the power company but not you?

I worked for many years on a military installation where they had electricians actually PM distribution panels. When they PM'd the panels in my shop the feeders would always need a 1/2 turn or so to make them tight. I asked the sparky why they were always loose and he said that it was the aluminum wire, the nature of the beast, and that they seldom saw that with copper.

The power company can run what they want as they are responsible for their side. Since anything past the meter is my responsibility, it will be copper.

 

[walta]

How sure are you that 200 is enough for the house? If the house is total electric 200 could get tight.

Walta

 

[rmack898]

Cooking, hot water, laundry, fireplace will be gas. A/C will be the biggest load in the house.

 

[rmack898]

Power next to data lines causes interference, especially if ran parallel for any noticable distance. I avoided this by putting fiber in my conduit next to the power conduit rather than copper. Depending on the distances & how close it may or may not end up being an issue. This goes for Ethernet as well as coax cable or phone line & DSL. You obviously have more control over this if you are running Ethernet between buildings than getting a line from the phone or cable company.

The cost of multi-mode fiber isnt actually that much worse that copper Ethernet. But it is a lot more fragile & really can't be terminated by a home user. That means you have to pull it through the conduit with the connectors on. The gear on either end is a a bit more expensive & complex as well.

Sent from my SM-N950U using Tapatalk

So are you saying that if I put a data line in the same trench as a power line separated by 2 feet of dirt, I will have interference issues?

 

[cbacres]

Mac, unless power co specifies, sch 40 for the run to the pole is fine. When I ran my conduit for the power co, they wanted galv for the long radius 90, but it was primary, not secondary, hopefully you can stick with PVC.

I'd bite the bullet and stick with the copper also.

I also go along with extra conduits, you may want a camera system you can see from the house, alarm , etc. I'd run one for each of those as you don't know what you may come up against wire wise in the future, may even go 1-1/4" conduit.

Interference wise, I don't know on that one, but I've read where a lot of guys have done just what you're planning on. With all the shielded cable out now, I wouldn't think it'd be a issue.

The 200 amp for the house should be fine unless you're building a mansion. We have about 2,200 SF, all electric, pool, two well pumps and the shop all on 200 amp.

 

[sberry]

Most of the world's power goes thru alum wire. I can't even remember the last time I used copper underground. Ain't no way no how I would spring for that much copper for a common service.

 

[tarmy]

I had a similar set up...200A for the house and another for the separated shop.

I too had to run 3”...4’ Deep. Smartest thing I did was to run two 3”. 1 2” and 4 1” in the trench.

Used the 2 3” for the service to each structure (built a couple years apart). Ended up using the 2” and 1 of the 1” to run a generator and control wire from behind the shop to the house. Installed a gate and cameras at the front of my property...used more of the 1” for those. Finally installed some flood LEDs in the trees to provide lighting...

Used every one of those conduit...all 40 sched.

Think about dropping a couple extra runs on the trench while you have it open.

I also made the trench extra wide and dropped a water line for stand pipes as well. The inspector also allowed a propane line and irrigation line.

Sand, then water, sand, propane, sand then power. The power was on one side of the trench, higher than the other lines that contained liquid/gas.

Good luck OP.

 

[Glory]

My 2cents

Run the sch 80 of your going through a forest at 36”. Most tree roots are in that range.

The copper will be pricey, shop local supply houses pricing - they vary more than you think.

For comms or “future” run at least (1) 1-1/2” conduit.
I would run a spare conduit, the same size as your primary.


Price out everything and then add 20% for contingency, trust me you will need every cent of that contingency.

 

[sberry]

I have never needed a spare conduit where the primary one wa's and certainly not and identical one. One time in 40 years I added anot her phonein and didn't use the same route. Anything I ever added extra has been abandoned.
This ISNT a military instalation, it's residential. It won't be loaded like some specific feeders might. I haven't found loose connects on alum especially at meter bases and actually have tightened old copper. If I had to check a lug 20 years from now I would. Had one apart the other day I did about that long ago and it was just fine.
Last I nm looked 4/0 alum quad was about 4 a foot, how much is 3/0 thwn?

 

[sberry]

I just looked. Not quite as much as I thought, 3 a foot. So around 10 bucks with ground

 

[sberry]

If you know you need it then it's still contingincy? 3 inch 40 is probably 20 or 25 a stick and 80 at least double that. Bet a 36 radius is 50$

 

[ard]

If you want to add a (a) powerwall, a (b) Generator or (c) Solar....how will that be added to the system the POCO has designed for you????

Will it need to tie into a 400A service mounted on a pole in the middle of the field? Just saying....


My point is consider future uses and additions. POCO rules and NEC rules can turn into surprises later. I like having the service on a building

 

[rmack898]

If you know you need it then it's still contingincy? 3 inch 40 is probably 20 or 25 a stick and 80 at least double that. Bet a 36 radius is 50$

Local supply house has 3"sch40 for 12.85 / stick, 36" radius is $18.

I'm going to run 1-1/2 data from the pole to the J-box at the meter base. I'll run two 1" pipes from the J-box to the house and two to the shop. I'll most likely will never use the data pipe from the pole as I am out in the sticks and I don't see them bringing in cable or fiber anytime soon, most likely not in my lifetime but I'll put the pipe in anyway.

The 1" pipes from the house and shop to the J-box will get used for cat5 and coax and who knows what else.

I will also run two 1" pipes from the house to the front gate (about an 800' run) One will be power for the gate opener and the other will be cat5.

 

[tarmy]

Local supply house has 3"sch40 for 12.85 / stick, 36" radius is $18.

I'm going to run 1-1/2 data from the pole to the J-box at the meter base. I'll run two 1" pipes from the J-box to the house and two to the shop. I'll most likely will never use the data pipe from the pole as I am out in the sticks and I don't see them bringing in cable or fiber anytime soon, most likely not in my lifetime but I'll put the pipe in anyway.

The 1" pipes from the house and shop to the J-box will get used for cat5 and coax and who knows what else.

I will also run two 1" pipes from the house to the front gate (about an 800' run) One will be power for the gate opener and the other will be cat5.

My gate was 550’...so calc your voltage drop for that run...wire size will become an issue potentially in that 1”...

The other thing I would suggest...put pull boxes in to longer runs so that it is easier to fish the wire through. Before I backfilled the trenches...I bought a vacuum fitting and the fish line and plugs from Amazon and sucked the nylon line through all the conduit. That way if I had a problem or failure I could fix it before filling the trench. After...I had no issues with pulls.

 

[wyliesdiesels]

New house, new shop on 10 acres and utilities will be underground.

I met with the power company engineer to discuss my needs and where we are going to bring in power. I will have a 200amp service for the house and 200amp to the shop. We decided that I will put in a 400 amp, meter/2circuit panel that will be located between the house and the shop and each building will have its own 200 amp breaker. The run from the pole to the meter base is 215' and I have to put in the pipe. They want 3" pipe, 36" deep with 36" radius ells. All of this pipe run will be through forrest, is there any need for sch.80 pipe or will sch.40 be adequate?

Next question: The run from the meter base to the house is 115' and to the shop is 95'. I have no reference books here in my camper but my gut feeling is telling me that I'm going to need 1Ga copper (I'm not using aluminum) or can I get away with 2 Ga? Can I fit that in 2" pipe or do I need to run 3"?

I will be adding a data pipe while I have an open trench. My thought is 1" pipe from the pole to a j-box at the meter for a co-ax run, and then 1" from the j-box to the house for co-ax and cat5, and 1" from the j-box to the shop for cat5. Am I missing anything? I only want to dig once.

Keep in mind that since you will have disconnects at the meter, you will need 2 run 4-wire feeders to the house and shop. The subpanels in each will need to have isolated neutral bars which usually means a separate ground bar kit will need to be added.

 

[rmack898]

I got all of my pipe in the ground and I will be installing the meter base/distribution panel in the next 2 days.

I bought this panel

https://www.worldelectricsupply.com...ka-3-wire-2-circuit-ringless-meter-main-22849

The panel will be mounted to a wooden structure that will be bolted to a concrete foundation. Once I get the panel mounted and the pipe connected to the panel, the electric CoOp will come out and pull the cable from the pole to my panel. This will be a 400 amp service. My question is will the Powco install the ground rod at the meter base or is that something that should be done prior to having them pull the service cable. If its on me to do, what size ground conductor will be needed for a 400 amp service and will I need one ground rod or two at least 8' apart?

 

[Bert_]

I got all of my pipe in the ground and I will be installing the meter base/distribution panel in the next 2 days.

I bought this panel

https://www.worldelectricsupply.com...ka-3-wire-2-circuit-ringless-meter-main-22849

The panel will be mounted to a wooden structure that will be bolted to a concrete foundation. Once I get the panel mounted and the pipe connected to the panel, the electric CoOp will come out and pull the cable from the pole to my panel. This will be a 400 amp service. My question is will the Powco install the ground rod at the meter base or is that something that should be done prior to having them pull the service cable. If its on me to do, what size ground conductor will be needed for a 400 amp service and will I need one ground rod or two at least 8' apart?

If you set the meter base then it's probably on you to install ground rods.

Unless you prove 25 ohms or less you need 2. The grounding electrode conductor for rods never needs to be larger than #6

 

[rmack898]

Thanks Bert

I can' find the reference but I remember from my last shop the the 2 ground rods needed to be at least 8' apart and that the grounding electrode conductor needed to be one uninterrupted piece of wire from one rod to the other and then to the panel.

Is this still the correct way to install a ground on a service entrance?

Also, can the ground electrode conductor be wire tied to the outside of the 3" conduit or does it need to be protected in it's own conduit to the ground rod?

 

[Bert_]

Thanks Bert

I can' find the reference but I remember from my last shop the the 2 ground rods needed to be at least 8' apart and that the grounding electrode conductor needed to be one uninterrupted piece of wire from one rod to the other and then to the panel.

Is this still the correct way to install a ground on a service entrance?

Minimum of 6'. The wire to the first rod is the grounding electrode conductor and must be continuous except by irreversible splice. Between rods is a grounding jumper and does not need to be one continuous wire to the panel.

Since you will be running #6 it does not need to be protected from damage.

 

[rmack898]

Thanks Bert

 

[reader2580]

I have never needed a spare conduit where the primary one wa's and certainly not and identical one. One time in 40 years I added anot her phonein and didn't use the same route. Anything I ever added extra has been abandoned.
This ISNT a military instalation, it's residential. It won't be loaded like some specific feeders might. I haven't found loose connects on alum especially at meter bases and actually have tightened old copper. If I had to check a lug 20 years from now I would. Had one apart the other day I did about that long ago and it was just fine.
Last I nm looked 4/0 alum quad was about 4 a foot, how much is 3/0 thwn?

My house the aluminum neutral in the load center from the meter was so loose that several inches of insulation was bubbled up from heating. Hots were also slightly loose.

 

[alfredeneuman]

Minimum of 8'.

250.53(A)
(3) Supplemental Electrode. If multiple rod, pipe, or plate electrodes are installed to meet the requirements of this section, they shall not be less than 1.8 m (6 ft) apart.

 

[Bert_]

250.53(A)
(3) Supplemental Electrode. If multiple rod, pipe, or plate electrodes are installed to meet the requirements of this section, they shall not be less than 1.8 m (6 ft) apart.

Right, 6' it is. I mis-typed

 

[rmack898]

I got the foundation and mounting frame installed for my meter base/distribution panel done. I was waiting for the 3" hub to attach the pipe to my meter base.

The meter base will accept overhead or underground feed entrance. The overhead entrance has 4 tapped holes for the hub and is already punched with a gasket cover. The bottom (underground entrance) is not punched and the hub is not concentric with the knock outs in the panel. The knock outs for the hub bolts match but I will need to use nuts and screws to attach the hub. My question in the non-concentricity of the knock outs with the hub. Should I just punch enough of the knock outs to give a full opening to the hub? Do I need some kind of grommet or bushing to protect the cable at the entrance?

 

[rmack898]

I forgot to show where the panel will be mounted.

 

[Bert_]

You only use the hub if you're going in the top of the box. if you're going in the bottom or sides then you just use standard connectors.

 

[rmack898]

I got the meter base/ distribution panel installed tonight. ( see pics)

My next question is about the entrance to the sub panel in the shop. I will be running 2" conduit from the meter to the shop. should the 2" come up through the footing and floor into the shop, or should I just run it outside the shop and have an LB where it goes through the outside wall into the shop panel.

 

[ard]

I got the meter base/ distribution panel installed tonight. ( see pics)

My next question is about the entrance to the sub panel in the shop. I will be running 2" conduit from the meter to the shop. should the 2" come up through the footing and floor into the shop, or should I just run it outside the shop and have an LB where it goes through the outside wall into the shop panel.

I prefer the clean approach from under the slab directly into the wall or box. Avoids having to frame around the LB; avoids a shell penetration.

Id also toss in 1 or 4 extra conduits. In a spread of sizes. the rest 1" and one or two low voltage 3/4"s

 

[mcbane]

So are you saying that if I put a data line in the same trench as a power line separated by 2 feet of dirt, I will have interference issues?

2 ft separation is good if you are using shielded cable. I would suggest putting in a separate PVC conduit and pulling cat 6e cable, which is shielded. Conduit will allow you to upgrade when the next network cabling standard emerges.