Dock Electric

B

bigbearelec

Member
Location
Long Island
Occupation
Electrical Contractor
I have a job that the dock is 550' from the closest electrical panel and the contractor wants to install a dock tower. We are trying to design it right now and we keep on getting hung up with the Voltage Drop. Is there a way we can do this without run 250KCmil for at 50A dock tower ??? Please I'm interested in good ideas.
 
What are you using as an amp value for the VD calculation? If you want to avoid larger conductors the one option may be step up/step down transformers. What is the available voltage 120/240? 480 with a step down at the end would work as well if that's available.
 
Not sure how he is calculating but the Southwire app indicates for 240V 50A 550 ft and 5% VD use of #2 copper will work. I would not put out onto a dock anything but copper anyway. Even at 3% it is only a 1/0.
 
Fred B said:
Not sure how he is calculating but the Southwire app indicates for 240V 50A 550 ft and 5% VD use of #2 copper will work. I would not put out onto a dock anything but copper anyway. Even at 3% it is only a 1/0.
Click to expand...
He is getting 250s because he is entering in 120V into the calculation instead of 240V @ 3%VD. Could go like a quarter mile with 250s.o_O

Tell the contractor that voltage drop is calculated using the L-L voltage, not the L-G voltage when you're installing a sub panel.
 
bigbearelec said:
120/240v I was thinking about the transformer but house is in wetlands so was worried about that.
Click to expand...
You mentioned a dock and a wetland, not related to your question but do take a look at Articles 555, and 682 as you'll run into a bunch of requirements around that.
 
You must log in or register to reply here.
Top