sparkyrick
Senior Member
- Location
- Appleton, Wi
Can you use them everywhere, or just cold locations only. This came up when replacing lamps for a road sign.
HO lamps marked "For Cold Temperature Use Only"
- Thread starter sparkyrick
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- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
From the specification page of a representative GE lamp:
When used at temperatures above 70 ?F their output is lower than a comparable non-CT lamp. I would expect the life to be dramatically reduced too, but the data sheet does not give that information.
The GE lamp appears to be compatible with regular HO ballasts. No indication that a Cold Temperature ballast is required. The minimum rated starting temperature of the lamp and ballast appears to be around -22?F
Where does it say that?
Those lamps are made for signs that operate year round half the time it is way above 70F and work fine.
I use those in my shop ,During the winter it is cold well below 60F and they work fine ,and in the summer it is warm well above 70f and their output is uneffected by the heat and they last just as long as they did before they added the letters CT on them.
On the other hand the 95 watt lamps lose output below 70f and constantly flicker,So I do not install them anywhere.
- Location
- Massachusetts
I am lost here.
If a lamp specificlly says "For cold temperature use only" how can there be any questions?
It says what it says very clearly.
If a lamp specificlly says "For cold temperature use only" how can there be any questions?
It says what it says very clearly.
That is correct , But if you want your 8' 2 lamp High output fixturs to work the way they chould then you need the 110 watt lamps , which are only available as cold tempature use only lamps.
The energy saver 95 watt lamps do not warm up unless it is above 70f
- Location
- Massachusetts
The lamps the OP has are marked cold temp only, not all HO lamps are marked that way.
I think the OP has jacketed lamps like we used to use in freezers.
Yes I know,.
I could be wrong but I do not believe you can get 110 watt HO's without the CT rating on them anymore.
"jacketed lamps"sounds good I've never used those as of yet.
The LED's are making all those fixtures disapear fast these days.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
It says that in the data sheet for the specific GE lamp I linked to.
There is a footnote which gives the condition to not use them where the ambient rises above 32F.
There is also a graph of light output versus temperature that compares a CT and non-CT lamp. The CT lamp has a higher output up to about 70F (the scale on the graph is hard to read). At that point two things happen:
1. The light blocked by the jacket (~3%) is more than the difference in base output.
2. You are near the region where the output of both types decreases with increasing ambient temperature and the jacketed lamp will be running hotter than the standard lamp. Compare the temperatures for both types at which the light output is at a maximum.
The comment on reduced life is a generalization on any lamp equipment, and fact that the internal temp of the jacketed lamp will be higher than the unjacketed.
How large the effect is is an open question since no comparative life versus ambient figures were given.
However, as other posters have indicated, the reason for "Not to be used ..." wording as opposed to the "Designed for use..." wording on the lamp you have is probably is based on the energy code requirements rather than the usability and life figures.
You are required by NEC to use the equipment according to the manufacturer's instructions, although you will not be inspected after changing lamps.
It says that in the data sheet for the specific GE lamp I linked to.
There is a footnote which gives the condition to not use them where the ambient rises above 32F.
There is also a graph of light output versus temperature that compares a CT and non-CT lamp. The CT lamp has a higher output up to about 70F (the scale on the graph is hard to read). At that point two things happen:
1. The light blocked by the jacket (~3%) is more than the difference in base output.
2. You are near the region where the output of both types decreases with increasing ambient temperature and the jacketed lamp will be running hotter than the standard lamp. Compare the temperatures for both types at which the light output is at a maximum.
The comment on reduced life is a generalization on any lamp equipment, and fact that the internal temp of the jacketed lamp will be higher than the unjacketed.
How large the effect is is an open question since no comparative life versus ambient figures were given.
However, as other posters have indicated, the reason for "Not to be used ..." wording as opposed to the "Designed for use..." wording on the lamp you have is probably is based on the energy code requirements rather than the usability and life figures.
You are required by NEC to use the equipment according to the manufacturer's instructions, although you will not be inspected after changing lamps.
I hope not....:lol:
Okay thanks,I can see your point about the. Jacketed lamps..:thumbsup:
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