Pad mount transformer

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bjp_ne_elec

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Southern NH
I'm looking at a job, and from what I've gathered in talking to property owner that our local POCO (I live in SE NH) is telling him there will have to be a pad mount transformer on the property. I have never dealt with a pad mount transformer - keep in mind when I was active in the trade (17 years ago) the majority of residential services were all overhead. If there was a transformer, it was on that pole.

How do these pad mounts get piped? Does the PVC stub up in to the bottom?

I'll be talking to the local POCO today, and I'm assuming that they'll be taking care of the primary side of the pad mount - pipe, wire, etc. As I'm going to be bidding this, I'll obviously need to understand this.

Thanks
 
Pad mount transformer

You got it. You sometimes have to dig down and furnish a 90 degree PVC under the pad. Most of the time the Power Company will do that. I'm with you when I started in 1972 most were overhead. Semper Fi. Buddy
 
The POCO will usually provide you with a drawing and specification for location and arrangement of the secondary conduits. It will usually detail the exact area and dimension of the stub-up in relation to the primary's and/or other surrounding features.
 
You need to get all information from the POCO. Where I live, if the service is 200 amp or smaller residential, you provide conduit into the transformer and they provide wire up to 150'. If it is over 200 amps residential or if it is commercial, you provide pipe and wire.

Jim T
 
Brady Electric said:
You got it. You sometimes have to dig down and furnish a 90 degree PVC under the pad. Most of the time the Power Company will do that. I'm with you when I started in 1972 most were overhead. Semper Fi. Buddy
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Might want to think about giving advise to someone about a power company you know nothing about that is about a thousand miles away. They all have their own requirements. The only way to know what a particular power company requires is to discuss it with that particular power company.
 
Definately call them up there in NH last time I did an underground up there they(POCO) did Supply the wiring to the Meter Socket as well as the Meter Socket. The only thing I did was install the Pipe Run and Meter Socket as well as the InteriorService Entrance of course. They(POCO) pulled the Lateral and terminated it as well.

Tom
 
As far as entering the concrete silo, we usually come in with the conduits through the side. There are areas of thin concrete that can be knocked out with a hammer. Two or more less sweeps to have to worry about.
 
In Colorado...

In Colorado...

I have done it both ways.

In Denver, Excel has ran the primary conduit, and I have ran the primary conduit, and sometimes they just run underground primary lines direct burial.

In Colorado Springs, everything is in conduit (duct bank). Sometimes Colorado Springs Utilities does it, most of the time it's us.

I agree. Make sure what the requirements are. I am bidding against a guy right now, and he included it in his bid. I didn't (by the way, he's $100,000 over me because of this... my point is it can be very expensive...)

Greg
 
Anybody got any pics of the conduits, pad, etc.? Love to see them. I've seen these transformers sitting in some of the new neighborhoods, but I have to admit, I haven't seen the inside of one.

Thanks

Dave
 
bjp_ne_elec said:
Anybody got any pics of the conduits, pad, etc.? Love to see them. I've seen these transformers sitting in some of the new neighborhoods, but I have to admit, I haven't seen the inside of one.

Thanks

Dave
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I dont know how that utility co works,
but are you talking about single phase t-former. in NY the single phase padmounts are a one piece unit set by them we provide the conduit and wire to a tap box (also part of the pad) and they take it from there (connections)

however if its a 3phase. we provide the following:

curb, pad, and subbase material (stone).

4/0 ground ring inside the pad, caldwelded with tails for the primary and secondary sides

(2) 4" pvc conduits for the primary side stubed out to just outside of the pad

conduits and wire (sized accordingly) to the secondary side

2hole crimp lugs, nuts,bolts, etc.. for the connection to the T-form spade and we have to wrap the entire spade in rubber tape.

we also need to provide the meter can, or we install the CT cabinet (supplied by them)

Man we do a lot for them!!!!!

Joe.
member of (Deleted)
 
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Bump - still hoping someone can post a pic or three showing conduits roughed in to a transformer pad. Most of my experience was commercial, so we'd elbow up in to the area of the pad, and then the pad would be formed and poured on the site. Always dealing with RMC on anything I did in my "past life".
 
I have a ton of pictures of the tranformer pads before and after installation of the transformer. If I have time later this weekend, I will figure out how to get them on this site.

An earlier poster gave some excellent advice that you will need to pay particular attention to. The different POCOs around the country provide different installation instructions for their own different requirements. I highly suggest that you contact them first, if you have not already. If I get my pictures up, they may not mean a hill of beans for you.
 
Pierre - I'm acutally meeting with a rep from the POCO today, to walk the site and spot the transformer pad's location. I'll be discussing specifics with him, and will post that later this afternoon. Thanks for agreeing to post some pics - appreciate the effort. You know what they say about pics.

Thanks

Dave
 
Met with the POCO, and their installation guide shows using a concrete pad, and the primary and secondary conduits come up in through the bottom of the pad. They specify a ground ring around the pad, two 5/8" rods driven kitty-corner, and laced with #2 bare - bringing 8' of wire in to and above the pad. Not sure what they're doing with the 8', but I'm guessing someone's collecting a nice stash of copper - He He. Steel sweeps for each end, unless the run is less than 120' (primary is 265', secondary is 110').

Pierre if you have any pics that might depict my scenario, I'd love to see them.

Thanks
 
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