chrisrappl
Member
- Location
- Raleigh
I have a plant with a large number of Holophane WL2K175MHMBBZF2 175w Metal Halide wall pack fixtures operating on 208v single phase power. They are less than ten years old and appear to be in good condition overall. I have two concerns with the original installation that I would like to address. The fixtures require 150 deg C supply conductors and are fed with 90 deg C THHN conductors. Where the supply conductors were not carefully trained away from the reflector and/or ballast, the conductors have overheated and the insulation is now brittle or worse. The other concern is that there is no emergency lighting or instant restart lighting in the areas served by these wallpacks. My plan at this point is to modify the existing fixtures to accept a self-ballasted CFL lamp that should reduce the heat generated in the fixture and restart quickly when interrupted. The lighting circuits are protected by a standby generator, so they should be energized within about 10 secs of a power interruption.
I cannot find 208v self-ballasted CFL lamps. They seem to be available in 120v and 277v. I could pull a grounded conductor in place of one of the existing branch circuit conductors, but this will be quite involved and there may be other lighting on these circuits that I will not be converting. I could try to install a grounded conductor in addition to the existing conductors, but again this will be quite involved and may not be possible.
I looked at the multi-tap ballast in the existing fixtures to see if I could backfeed it with 208v and end up with 120v. The closest that I have come is to feed the lamp and common leads with 208v, connect the socket leads to the 277v and com leads and splice the capacitor leads together. This gives me a measured voltage at the socket of 114.8v using a 75w/ 130v test lamp. I don't think that the multitap ballast is just a transformer, because my socket voltage is drastically affected by the lamp load. With no load the socket voltage is 142.2v as opposed to 114.8v with the test lamp installed.
I priced a simple 208v to 120v transformer, but that would add almost $50 to the cost of each fixture and I'm looking at about 150 fixtures to start.
The CFLs that I'm looking at are Maxlight #11271 60w/120v. The factory tech support says that this is a good application for that lamp and that it will not overheat in the enclosed fixture.
If anyone has experience with this, I'm open to suggestions. Maybe I'm looking at this all wrong. Or maybe there is another option that I haven't considered.
I'd appreciate any help with this one.
I cannot find 208v self-ballasted CFL lamps. They seem to be available in 120v and 277v. I could pull a grounded conductor in place of one of the existing branch circuit conductors, but this will be quite involved and there may be other lighting on these circuits that I will not be converting. I could try to install a grounded conductor in addition to the existing conductors, but again this will be quite involved and may not be possible.
I looked at the multi-tap ballast in the existing fixtures to see if I could backfeed it with 208v and end up with 120v. The closest that I have come is to feed the lamp and common leads with 208v, connect the socket leads to the 277v and com leads and splice the capacitor leads together. This gives me a measured voltage at the socket of 114.8v using a 75w/ 130v test lamp. I don't think that the multitap ballast is just a transformer, because my socket voltage is drastically affected by the lamp load. With no load the socket voltage is 142.2v as opposed to 114.8v with the test lamp installed.
I priced a simple 208v to 120v transformer, but that would add almost $50 to the cost of each fixture and I'm looking at about 150 fixtures to start.
The CFLs that I'm looking at are Maxlight #11271 60w/120v. The factory tech support says that this is a good application for that lamp and that it will not overheat in the enclosed fixture.
If anyone has experience with this, I'm open to suggestions. Maybe I'm looking at this all wrong. Or maybe there is another option that I haven't considered.
I'd appreciate any help with this one.
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