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#52594 - 05/30/05 08:42 AM Parking lot lighting circuit.
cgw Offline

Registered: 07/29/04
Posts: 133
Loc: Rochester NY
Can a larger than 50 amp circuit be run for pole mounted HID lighting with fuses at the poles?
Is there a practical limit to the size of wire or circuit size run in a 3 phase circuit to poles? 208 volt (voltage drop needs to be taken into account also)
Actually I am looking at a car dealership which has a higher wattage in a smaller area than a typical parking lot.

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#52595 - 05/30/05 08:54 AM Re: Parking lot lighting circuit.
livetoride Offline

Registered: 01/11/05
Posts: 109
Loc: san diego ca usa
We did this in casino parking lots, no problems. Rod

#52596 - 05/30/05 09:34 AM Re: Parking lot lighting circuit.
iwire Offline

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
In my opinion if you are talking about putting more than 40 amps of continuous load on a site lighting circuit @ 208 volts and you want to keep voltage drop within reason the wire size will get out of control.

Of course this will largely depend on distance.

IMO, running more circuits with less load will be more efficient cost wise.

Say you end up needing 2 AWG for your circuits, now you end up with raceways that will not fit in the poles so you need hand holes in the ground beside the poles. Then the time and matrial for splicing the larger conductors.

By using more circuits if there is a fault you do not darken the entire parking lot.

I would look into kicking the voltage up to 480 for the site lighting, voltage drop and circuit loading problems are greatly reduced.

Bob Badger
Construction & Maintenance Electrician

#52597 - 06/01/05 06:07 PM Re: Parking lot lighting circuit.
DiverDan Offline

Registered: 03/10/05
Posts: 38
Loc: Sacramento, CA
Don't forget about ambient temperature as this affects voltage drop as much as distance. Not to be a commerical, but try Volts' Series Voltage Drop module.
Dolphins Software

#52598 - 06/02/05 11:57 AM Re: Parking lot lighting circuit.
Steve Miller Offline

Registered: 08/30/01
Posts: 322
Loc: Loudoun Cty, VA
Is 277/480 available? We run at least 277 and often 480 to our school parking lots. Makes the wiring real easy to handle.


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