Volt Amps Vs Watts

Bkessler

I need a step down transformer that goes from single phase 208 to 110 that is 350-500 watts strong, how does 500 watts in a transformer like this compare to volt amps. thanks bk

mahlere

about the same

http://www.the12volt.com/ohm/ohmslaw.asp

mdshunk

If you discount power factor, volt-amps and watts are essentially the same.

Bkessler

Thats what I thought MD so thanks for clearing it up for me. bk

Sparky Joe

Isn't 208 and 110 the same system?

Instead of buying a transformer just exchange your red wire for some white wire.

Bkessler

The last electrician to try and pull wire through these conduits for outlets in the center of the parking lot for a xmas tree, had to take down the pole (about 20 footers) and I need a 110 outlet on each pole for 250 watts of garland. AND the city who owns these poles and the electrician who maintains them says pulling a couple of wires through is not worth it. My plan to install the 3r stepdowns should only take me 2 days and be some what affordable for the tax payers! Also the plan is to disconnect a few lights to make up for the xtra wattage!

Sparky Joe

Keep in mind that lighting loads, especially parking lot lights are almost always circuited to their maximum ampacity. So tapping off the circuit to run 250 watts of festoon lighting is probably not an option.

You need to take an amperage reading at the panel to see what the circuit is drawing, and keep in mind that 16 amps on a 20 amp circuit is maxed out for lighting loads (continuous load).

Oh and if the electrician that did this before cared about getting a project done rather than making pure profit from markup on a crane rental, he could've easily got another wire in the conduit without taking the pole down

mdshunk

Indeed, customer owned parking lot lighting often is. Municipal owned roadway lighting is often quite the opposite. It will either be unfused, fused very high, or fused in each handhole. Roadway lighting is a (scary) horse of another color.

Bkessler

Your right, it is almost peaked out but, this is for a city hall parking lot, I told them and they were already well aware that they would have to disconnect a few lights ( like Half ) to have the festoon light going, The really funny part is they had an electrician ten years ago tap the 208 and put a LL20 in a bell on the top of the pole for old 220 festoon lighting, this year they had a new company come in and sell them new xmas lights and hang them. THe 110 cord is just hanging there. And that's hard earned tax money at work!

james shillady

looking for efli theroys

mdshunk

You're in luck. I have several right here.