Transformers and Feeder

[kwired]

If it were me (and granted making some assumptions not knowing a lot about the project, I would go two sets of 250 or 350 URD (triplexed USE with 2 sizes reduced neutral) in 4" SDR35 sewer pipe for protection, no transformers. I would make the long run service conductors to avoid the EGC. Sounds like you have a future PV system at the beginning, but you can use 230.40 exception #3 to feed that and keep it a service all the way to the house.

I'd probably do same but with conductors already pre installed in HDPE. Would end up being two 2 inch HDPE runs instead of one four inch run, but you don't need to go through the labor to pull conductors through raceway(s). Just dig trench and lay it in similar to how you would direct bury cables. Can even plow it in if you have such equipment.

 

[electrofelon]

I'd probably do same but with conductors already pre installed in HDPE. Would end up being two 2 inch HDPE runs instead of one four inch run, but you don't need to go through the labor to pull conductors through raceway(s). Just dig trench and lay it in similar to how you would direct bury cables. Can even plow it in if you have such equipment.

Yeah CIC seems like the best way to go in situations like this. IVe only tried to get CIC a few times Once was for a very unorthodox custom step up step down system at 2.4kv using (2) 5KV airport lighting conductors and a single 600V neutral (MGN with two separately metered supplies). This was 4 years ago and the project didnt end up happening but I did get a quote for the custom CIC run of about 4000 feet and it was definitely a no brainer to use the CIC.

Last year I tried to get some 15KV CN URD in CIC but I couldnt find it (thought it would be a common stock item as I have seen utilities use it) and no one seemed willing to run it. You get into long runs that are too long for a single pull and either have to use hand holes, direct bury (with protection such as sand if necessary), or sleave conduit over it. On the 15KV job we ended up sleaving 1.5" PVC over it, 1700 feet. Sounds worse than it is. You start at each end so only have to go 850 feet to the middle, and it gets 40-50 feet shorter every time.

 

[kwired]

Yeah CIC seems like the best way to go in situations like this. IVe only tried to get CIC a few times Once was for a very unorthodox custom step up step down system at 2.4kv using (2) 5KV airport lighting conductors and a single 600V neutral (MGN with two separately metered supplies). This was 4 years ago and the project didnt end up happening but I did get a quote for the custom CIC run of about 4000 feet and it was definitely a no brainer to use the CIC.

Last year I tried to get some 15KV CN URD in CIC but I couldnt find it (thought it would be a common stock item as I have seen utilities use it) and no one seemed willing to run it. You get into long runs that are too long for a single pull and either have to use hand holes, direct bury (with protection such as sand if necessary), or sleave conduit over it. On the 15KV job we ended up sleaving 1.5" PVC over it, 1700 feet. Sounds worse than it is. You start at each end so only have to go 850 feet to the middle, and it gets 40-50 feet shorter every time.

Before shortages last year CIC was the way to go for any long runs for me- like at least 5-600 feet or longer, less than that started to make it not worthwhile simply because of where I have to go to pick it up from.

Luckily (maybe) I didn't need to get any last year, but heard it was nearly impossible to get, before that they always seemed to have plenty of stock and unless you wanted cut lengths was pretty much available on demand.

Most my use has been for irrigation applications, 1200 - 2800 foot lengths is pretty "normal" in that kind of work.

 

[electrofelon]

Before shortages last year CIC was the way to go for any long runs for me- like at least 5-600 feet or longer, less than that started to make it not worthwhile simply because of where I have to go to pick it up from.

Luckily (maybe) I didn't need to get any last year, but heard it was nearly impossible to get, before that they always seemed to have plenty of stock and unless you wanted cut lengths was pretty much available on demand.

Most my use has been for irrigation applications, 1200 - 2800 foot lengths is pretty "normal" in that kind of work.

Were these custom runs you have gotten or stocked configurations?

Yeah it was (and still is) tricky last year. The "normal" price of #2 15KV CN was about $1.90/ft. When I went to order it a few weeks later (this is stocked item at the supply house here) they were like sorry, its $3/ft now. I was able to find it for $2.5 after calling around but had to jump on it so just gave up on trying to find it in CIC.

 

[electrofelon]

I did one last summer that was 7620 - that is probably the most common MV distribution voltage in the country.

Just a little correction. That was supposed to be 7200 above (12.47) phase to phase). 13.2Y/7620 is the most common 15 kV class distribution voltage used by national grid here in upstate New York, so I get those mixed up.

 

[kwired]

Were these custom runs you have gotten or stocked configurations?

Yeah it was (and still is) tricky last year. The "normal" price of #2 15KV CN was about $1.90/ft. When I went to order it a few weeks later (this is stocked item at the supply house here) they were like sorry, its $3/ft now. I was able to find it for $2.5 after calling around but had to jump on it so just gave up on trying to find it in CIC.

Stocked configurations. Pretty fair variety of commonly demanded configurations though. Even some "specialty configurations" yet common demand for certain applications, such as a configuration of three larger aluminum conductors plus an EGC for the power conductors and two 12 AWG copper conductors as signaling/control conductors or even is common to desire a center pivot control panel to be located remote from center pivot and with such you can get four aluminum power conductors (EGC included) and ten 12 AWG copper control conductors. Probably little demand for that kind of configuration outside this area though and would be something you would have a lead time on if you wanted it elsewhere (before the last couple years anyway).

I seem to recall asking about getting just "triplex" 4/0 aluminum CIC one time and it actually cost same or less to just purchase the in stock "quad" they normally stocked and just not use one conductor.