4800V Primary Service Installation
Hello All:
I hope to start building a new home in early July. I’ll do the wiring inside the house to the meter. The only accessible electric service pole is 450 ft away and the deed requires the service cable to the new house to be underground. The deed does contain all the easements needed for us and the utility. NYSEG, the local utility, has specified a 4800 Volt primary service because of the losses due to distance. NYSEG doesn’t install these services on private property and I’ll need to contract with an electrician to dig the trench, install a slab and transformer vault, install conduit and install the cable.
I’d appreciate suggestions on important points that should be clarified when discussing the project with the local electrical contractor(s).
Many thanks.
greg
Replies
Greg, just got done doing this same job. 15kv URD burial cable, 440' underground run from a NYSEG pole to transformer vault. I'm just north of Binghamton.
I did all the work myself. Here's what I can offer:
Shop the wire around, big price differences. 2.50 per foot at one place, 1.80 at another.
30" deep trench, 6" sand in the ditch bottom and over the wire.
Cut sheet for the wire to NYSEG engineer prior to purchasing.
NYSEG charges a lot to do wire terminations at transformer.
Andy
Transformer vault? That would infer the transformer will be below grade - normally (at least around here) the transformer sits on a small pad on grade. For a residential application, it's usually one of those small square green cubes that are around 30 or 36 inches square. It is usually supplied by the electric utility, and they either provide specific requirements for a concrete pad to be made on site, or a prefabricated fiber cement style that is set on a gravel bed.
Clarify:
1) who's digging the trench, him'er you (I try to get my customers to do the digging)
2) who's going to own/maintain the service lateral and transformer once it's installed (you or the power company)
3) the type of longevity you want (pipe is better)
I'll type more later if I think of it.
Ed
OK, 2 more. First, obviously, you need to determine the size of the thing.
2nd, do you have any special grounding concerns, like is your site on a hill exposed to nasty electrical storms where you might want some extra protection.
Ed
I would ask the power company if they have a booklet with the specs included.
Here it's up to the customer to provide the trench and conduit, they pull the cable & supply transformer & connect it. They expect you to remember to put the pull rope in too, don't forget it.
Here too, green transformer box above ground.
Seems like I could dig a trench cheaper than most electricians, conduit and sand aren't rocket science either. Course I'm a cheap SOB so prices may vary.
Joe H
Well, I see that already several replies have started off on the wrong track....
Your absolute first stop should be at the engineering department of the utility. I guarantee that they have standards that cover everything right up to the meter.
You'll need to provide the correct pipe up the side of the pole for them to pull their wires into. This pipe will have to enter the correct place on the correct transformer pad. Most likely, another pipe will be required to feed the meter. These pipes will likely need to be buried 5 ft. down, with proper fill, and numerous inspections along the way by the utility.
You will likely have to erect barriers to protect the transformer. There will be standards as to how you need to do this. If you plan to plant bushes around the transformer, the standards will detail how you may do this.
Unlike the NEC (which applies after the meter), PoCo standards vary greatly by Utility. many Utilities have their standards accessible, free, on the internet.
Les obvious, the PoCo may have requirements for the electrician you hire. They may require him to be registered with them, hold a "Master Electrician" certification, etc. They may require an Engineer sign off on your plans.
Greetings IMP !
A few thoughts spring to mind, & rather than cross examine you to determine all the plans you are considering I'll offer some conditional suggestions you may need to consider (or not.)
1) Resolve where all your vehicle traffic will take place both presently & in the future. Underground conductors need differing levels of protection depending on this point. A contractor will need to know.
2) Resolve if any outbuildings will be built now or in your future and if they might require an electrical service. A large shop of large demand might dictate a centralized location for the transformer to minimize the low voltage cable run lengths to house & shop. You may also need a central metering system if this is the case.
3) If that 450' distance means you are in a rural area you might want to consider the inclusion of a Transfer Switch to allow for a back-up generator connection.
4) Give some thought to future expansion of service demand: you may want a larger than just-adequate transformer or supply conductors to the house if your needs increase sometime later.
5) Consider landscaping needs. You may want to bury your conductors deeper than minimum code to allow for some later landscaping requirements.
6) Think about other services ie. Tel, TV Cable, Gas, Water, Sewage, Outdoor lighting, lawn, irrigation etc. Good planning now may simplify their installation. (A trench for multi KV conductors is generally not a good place for anything else.)
7) Think about documenting by photo and map the trench locations for future reference. Once the vegetation grows back it can be difficult to remember just where that trench is located. (Include some permanent features for referencing )
Regards,
STAINLESS