New 3 Pz Hook Up Question

jpfabricator

jpfabricator

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Im getting 200amp 3phaze delta wired into my new shop (3 pz was a few $ more, so what the hay right!)
I have my meter box and mast installed with a weatherhead as per the po-co's instructions.
My question is what size wire do I need to run from the weatherhead to the meter mount?
My installation paperwork and requirements did not specify, and I dont seem to be able to find it on the WWW.
So if any electricians can tell me what the N.E.C. states I would be obliged!

Sent from somewhere in East Texas Jake Parker
 
jpfabricator said:
Im getting 200amp 3phaze delta wired into my new shop (3 pz was a few $ more, so what the hay right!)
I have my meter box and mast installed with a weatherhead as per the po-co's instructions.
My question is what size wire do I need to run from the weatherhead to the meter mount?
My installation paperwork and requirements did not specify, and I dont seem to be able to find it on the WWW.
So if any electricians can tell me what the N.E.C. states I would be obliged!

Sent from somewhere in East Texas Jake Parker
Click to expand...
 
I agree with the wire size suggestion made by Bob.

Why going with Delta? I am new to machine shops, but delta would not be my first choice for a 3-Phase in a shop. I would want to go with 208 wye, which allows for easy 120V as well. I don't believe standard delta deployments allow for 120V unless they provide a neutral off of one of the phases. Not something I have run into very often.

208 wye allows for 208V between any 2 hots, and 120V between any hot and any neutral...very flexible
 
I bet it's Delta-wye. They'll be branching off of Delta system
 
I hope so, which from his standpoint what he is ending up with will be 208Y, which is exactly what I would want in his shoes...be very flexible.

I have seen places with delta/delta, but it is often 460V and they use on-site transformers to provide 208/120V. I have also seen delta/delta brought in with an additional smaller single phase service as well...one of the facilities I used to be responsible for had both a single and three phase service brought in, but that is because it started out as single phase and three phase was added later.
 
The machines I have came out of a 208/120 shop, so I figured why not. Plus the enginer said he could acomplish this set up with 2 transformer. This made the 3pz about the price of one VFD more than single pz.
Another bonus is most of the shops around this area are wired the same, so most surplus stuff is already wired for my shop service.


Sent from somewhere in East Texas Jake Parker
 
Mine is a Delta/Wye transformer at the pole. I'm not far from Jake, and most all of the East Texas area is wired this way, except for large industrial users.
Smaller substations in rural areas often output only Wye, depending on service area. However, in oilfield country, there are lots of active artificial lift systems that do run on 460/480, so I expect the Delta configuration is around also. There is a pump about 3 poles down from me. I may go have a looksee tomorrow if it dries out enough. We're getting drenched. DFW area has had a rough couple of days, and more tonight it looks like. Sabine River is about 12 feet above flood tonight and expected to rise a bit more. I'm about 20 miles from that though.

I hope all the H-M'ers are dry.
 
jpfabricator said:
The machines I have came out of a 208/120 shop, so I figured why not. Plus the enginer said he could acomplish this set up with 2 transformer. This made the 3pz about the price of one VFD more than single pz.
Another bonus is most of the shops around this area are wired the same, so most surplus stuff is already wired for my shop service.


Sent from somewhere in East Texas Jake Parker
Click to expand...

If it is just two transformers, it is probably a high leg open delta service, and not delta-wye. That should work just fine for you. Good luck!
 
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