Electrical Repair Questions? Ask an Electrician for Answers ASAP
Hi, Welcome to Just Answer. My name is XXXXX XXXXX would be glad to assist.
800 amp , single phase, 350 feet. Will this be in conduits or buried directly?
I'm not sure which route I want to go so am interested in an answer for both options
You have several options. There will be parallel runs.
im not sure what you mean by parallel runs
3 sets 400 mcm in conduit is an option 270 amp per set
What transformer is this? Power company?
we live in rural district and is a setting for grain facility/general farm operation
You cannot get 800 amps from just 3 cables. Takes multiple sets of 3.
So, multiple conduits
I assume you have already verified with the power company that they can accommodate you?
so i need 3 runs of conduit with 400 mcm triplex in each one? yes the power company has been notified and says that they have more than enough to accommodate us.
Tri-plex? Conduit would be single cables. THWN or the like. Triplex would be the underground cable in earth.
Insulation of the cable is very critical.
Do you know exactly what it is you have in mind? Manufacturer?
What size triplex would i need then if i did want to direct bury it.
what do you mean by manufacturer.
It is all about the insulation class of the manufactured cable
Here is an example:
With this cable, it would be 3 -350 mcm runs.
we are considering URD triplex
That is the same 3 runs- 350 mcm
Yes that is the wire we are considering. so can't i just run 400 mcm triplex and run that through pvc conduit and bury it
I am trying to understand, the cable is made for direct bury. You want to conduit it too?
yes. just for the ease of handling/running it through conduit. and thats what we've always done. is the loss of voltage less if run in conduit or has no effect
Cables are large, voltage drop is not your issue.
The key is whether you have to de-rate the cable in conduit.
so if i would run 400 mcm triplex in conduit and bury it, this would handle 800 amps single phase 350 feet away? is that correct? and if so what would be the approximate diameter of one of the strands of triplex?
1 run of 400 mcm triplex will not carry the 800 amps
I am finding the information, be just a moment. Thanks
Do you understand on the 400 mcm?
3 sets of triplex direct bury or in conduit (whatever I decide) would be sufficient. correct? as far as the 400 mcm I guess i really don't quite understand that -- is that wire size?
yes, it is wire size
diameter of the cables
3 sets will carry the 800 amp
I am trying just to verify putting underground cable in a conduit. Not common.
Diameter of 350 in that URD is 1.736" each cable
When you are going to purchase the cable, the company selling it should know on the conduit question.
thanks for answering my questions and your patience
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