[rjniles]

I have a mercury vapor yard light that has not worked in over a year. Decided to investigate (finally) and found that the ballast transformer is kaput. Rather than replacing the ballast if I could find one (the light is 20+ years old), I thought I could convert it to a CFL. The existing fixture has a 175 watt lamp that produces 7800 lumens (45 lumens per watt). I can get a 105 watt mogul base self ballasted CFL that will produce 7150 lumens (68 lumens per watt). Pretty significant increase in efficiency. The rewiring to eliminate the ballast is pretty straight forward.

Does any one see any downsides to my plan?

 

[Missouri Bound]

None whatsoever. I've done it myself. The CFL will take a while in cold weather and may not come up to full lumen output when very cold, but I'd bet that MV wasn't very bright either. Just remove the ballast and rewire, or better yet replace the socket if it's burnt or worn. Heat in those fixtures will weaken the center "spring" contact.

 

[dmxtothemax]

CFL's dont like to be in sealed enclosures
with no ventilation.
And with the larger 105w versions
probably more important.
If it's a cold enviroment you might get away with it,
But I suspect you will suffer from short lamp life.

It will be interesting to see how it works out !

 

[ddawg16]

SC does not get that cold so I wouldn't consider the weather to be an issue.

But you do want to give the bulb enough ventilation.

Otherwise, it will be a good swap.

 

[frenchelectrican]

I don't see that issue however make sure you bypass the ballast connection and if you want to keep the photoeye sensor it is pretty easy to do it.

If this is a common dusk to dawn luminaire some case just disconnect the ballast but do not remove due some of the common D/D lamp socket is welded on the ballast.

That super CFL you should get about 10,000 hours life but not excat the number I know some are rated at 8K to 16 K but expect about 12K is the norm.

With long burning hours the lamp life actually go little longer than it was adverised or rated.

Cold weather ? well it will be dim for few minuites until the lamp get warm then it will brighten up just like any other HID's but one nice advange is that you have instat restrike time which it means it will come back on quick instead of normal 3 to 15 minuites to come back on after mometary power outage or system dip.

Merci,
Marc

 

[bobelectric]

www.e-conolight.com wall pack is better choice.

 

[Missouri Bound]

CFL's dont like to be in sealed enclosures
with no ventilation.

Is that what it is? From the description I suspected it was like the old "street light" models, wal mounted on a short pole, open bottom.

 

[rjniles]

www.e-conolight.com wall pack is better choice.

Probably so but I am doing this on the cheap.

Missouri is correct, the fixture has plenty of ventilation.

Thanks to all that responded