Using 120v power on 277v lighting ballast

[beeker007]

Hello all,

I'm new to this message board and have what is probably a pretty novice-level question that I haven't been able to find an answer to elsewhere. The situation is as follows:

I put in a small backyard basketball court for my kids and wanted to add lighting for it. I found a nice 20-ft parking lot light pole that I think would fit the bill nicely. It has two 400w metal halide lights and should throw off sufficient light for my needs. The issue is that it's set up to work off of 277v vs the 120v residential power I have. So my question is whether the 277v ballast will work off of 120v power assuming I changed the bulbs out for metal halides rated for 120v? I have seen that some ballasts work for a range from 120v-277v, but the labeling doesn't indicate that is the case here. If I do need to change the ballast, would I specifically need to look for something that would support two 400w bulbs? Is there anything else besides the ballast that would need to be changed? How would I tell the wattage that's supported by the 120v ballast? If I went the LED retrofit route, obviously this wouldn't be an issue, but they're pretty spendy at this point. I don't plan on actually doing the wiring myself, but am just trying to scope out the costs. Thanks.

Chris

 

[Lassen Forge]

Nope, all 3 have to match voltage - Line, Ballasts, and bulbs. Check the ballast in the lamp you have (there may be one per bulb) and use your "Google Fu" to see if they either make a 120 volt version of that ballast, or show you how to hook up the existing ballast for 120. (you might be surprised)...

Since you have to convert them anyway it might be worth it to bite the bullet and do the LED conversion rather than buy new ballasts & Bulbs. Costs more now but the lifespan is so much greater (and a lot less in the power department) you'll save money.

 

[nehog]

Nope, all 3 have to match voltage - Line, Ballasts, and bulbs. ...

Metal halide bulbs don't have a voltage rating as such. I'd check to see if the ballast(s) have taps for other voltages, otherwise, you'll have to replace the ballast(s) with multi-voltage versions.

 

[Rookie2]

If you open up the fixture ,when you trace the 277v wire back to the ballast look for xtra wires on the ballast and a label. If it's a multi tap ballast , each xtra lead will be labeled on the wire for each voltage. At one time most were ordered with specific voltages.


There is a bunch on ebay:
http://www.ebay.com/itm/400-watt-Me...514971?hash=item210472379b:g:iNoAAOSwl9BWKNGS

 

[wyliesdiesels]

Some ballasts are multi-voltage/multi-tap as stated above...

Nope, all 3 have to match voltage - Line, Ballasts, and bulbs

Nope. HID bulbs operate at voltages different than the line voltage, sometimes around half the line voltage. When starting, a striking arc used to ignite the bulbs can have a voltage of 2.5Kv-4.5Kv...

Read pg 7 and 9:

http://www.howard-lighting.com/Documents/ProductLiterature/HIDLampServiceGuide.pdf

 

[Norcal]

277V ballasts do not even work well on 240V, the only hope is that the ballast is a multi-tap, 120/208/240/277V or change the ballast to a multi-tap.

 

[nehog]

277V ballasts do not even work well on 240V, the only hope is that the ballast is a multi-tap, 120/208/240/277V or change the ballast to a multi-tap.

Yup, close is not close enough!

OP: ballasts are expensive and generally not worth changing.

 

[beeker007]

I really appreciate the volume and quality of the responses. It looks like I'm probably out of luck as the lamp is definitely rated as 277v (no indication of multi-tap or other voltages). That said, it looks like replacing the ballast(s) is a pretty cheap affair ($50 - $75 for two off of Ebay). Will have to weigh that against the advantages of just going straight to LED (probably around $400 for two lights). This wouldn't be used for more than a few hours a week for around 6-8 months a year so electricity usage really isn't a big factor. Imagine LEDs will be much cheaper in a few years. Something to think about. Thanks everyone.

 

[Rookie2]

do a search on here for LED's ,someone posted that they used 8 100w equiv. in their garage and were tickled to death.

 

[Norcal]

I really appreciate the volume and quality of the responses. It looks like I'm probably out of luck as the lamp is definitely rated as 277v (no indication of multi-tap or other voltages). That said, it looks like replacing the ballast(s) is a pretty cheap affair ($50 - $75 for two off of Ebay). Will have to weigh that against the advantages of just going straight to LED (probably around $400 for two lights). This wouldn't be used for more than a few hours a week for around 6-8 months a year so electricity usage really isn't a big factor. Imagine LEDs will be much cheaper in a few years. Something to think about. Thanks everyone.

The lamp remains the same, the ballast is what changes.

If it is not going to be used a lot, swapping out the ballasts could be cost effective, LED is still expensive & life ain't what is claimed yet, wait until the price drops & life is closer to what is claimed, I personally don't care to pay a significant sum of money to be a beta tester.

 

[Slowgsr]

Change ballast will be the cheapest/easiest.