Drafting symbol for "High Efficacy Recessed Light Fixture"

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tallgirl

tallgirl

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Controls Systems firmware engineer
That's pretty much it.

A "Recessed Light Fixture" is a circle with an R inside. Wisconsin has a code requirement for "high efficacy lighting" and I'm trying to add the electrical layer to my plans ... since I didn't submit plans with the actual electrical in them ... and I figure there has to be a different symbol for high efficacy lighting.

Or just draw regular recessed light fixtures and inspector dude will just know they're high efficacy because they have to be?
 
hbiss said:
What the hell is "high efficacy lighting"? Maybe you mean "high efficiency"?

-Hal
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efficacy in lighting is how well a source produces visible light. Was maybe a bigger deal with fluorescent lighting than it is now, those produced UV light and the phosphor coating on the tubes was where the efficacy kicked in on how much visible light was given off. I think there is still some of this with LED's though.
 
kwired said:
efficacy in lighting is how well a source produces visible light. Was maybe a bigger deal with fluorescent lighting than it is now, those produced UV light and the phosphor coating on the tubes was where the efficacy kicked in on how much visible light was given off. I think there is still some of this with LED's though.
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The units are Lumens per Watt. The bulbs in the cans I'm using have an efficacy of about 60. Incandescent bulbs are about 10 or so. Bigger numbers are better.
 
kwired said:
Efficacy in lighting is how well a source produces visible light.
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Ok. Like how much visible light does it produce compared to IR, UV and heat per watt.

Not sure why there would need to be a symbol for them. I assume the fixtures for a given area or space would be specified by the architect or engineer in the specs.

-Hal
 
tallgirl said:
That's pretty much it.

A "Recessed Light Fixture" is a circle with an R inside. Wisconsin has a code requirement for "high efficacy lighting" and I'm trying to add the electrical layer to my plans ... since I didn't submit plans with the actual electrical in them ... and I figure there has to be a different symbol for high efficacy lighting.

Or just draw regular recessed light fixtures and inspector dude will just know they're high efficacy because they have to be?
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Whether it's a circle with an "A" or "B" or "C"......is whatever the fixture schedule says it is. Full description, cat#, lamp type, etc

Make a schedule...
 
cdslotz said:
Whether it's a circle with an "A" or "B" or "C"......is whatever the fixture schedule says it is. Full description, cat#, lamp type, etc

Make a schedule...
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Yep. Avoid the hassle, just define it in the schedule. I cannot tell you how many people don't use the standard symbols from NFPA 170 when they lay out a fire alarm project. Well, actually I can; all of them don't.
 
My two pence worth. We have eight recessed lights in our upstairs bathroom. Four are LED and four are Halogen. How would that figure in terms of efficacy ?
 
GeorgeB said:
Frequently manufacturers data sheets furnish that information.
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Even if they don't have it explicitly, you can calculate from the power draw and light output, which I'm sure the data sheet would provide.
 
Dumb question: is this efficacy measured as 'lumens of visible light output per watt of electrical input', or 'lumens of visible light output per watt of photon output'?

I believe I've seen both usages.

-Jon
 
winnie said:
Dumb question: is this efficacy measured as 'lumens of visible light output per watt of electrical input', or 'lumens of visible light output per watt of photon output'?

I believe I've seen both usages.

-Jon
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IMO, the first is “efficiency”, the second “efficacy”. But I’ve seen both called efficacy as well.
 
winnie said:
Dumb question: is this efficacy measured as 'lumens of visible light output per watt of electrical input', or 'lumens of visible light output per watt of photon output'?

I believe I've seen both usages.

-Jon
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Well, all the energy in comes out as photons of one wavelength or another, so it's all the same as long as you're using equivalent units.
 
winnie said:
Dumb question: is this efficacy measured as 'lumens of visible light output per watt of electrical input', or 'lumens of visible light output per watt of photon output'?
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Efficacy is the first one. Not sure what the second one is called or why you'd particularly care to measure that.

Cheers, Wayne
 
gadfly56 said:
Well, all the energy in comes out as photons of one wavelength or another, so it's all the same as long as you're using equivalent units.
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That would only be true in space, where all the heat loss is radiant, i.e. photons. But some of the heat loss will be conductive or convective, so some of the energy loss will be as heat. That is, increased average kinetic energy of the molecules of a substance.

Cheers, Wayne
 
wwhitney said:
Efficacy is the first one. Not sure what the second one is called or why you'd particularly care to measure that.

Cheers, Wayne
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I believe that the term efficacy is also used for 'luminous flux / radiant flux' and I don't know why one would use this. I simply remember it as a caution to beware of LED datasheets with seemingly high efficacy numbers, because these might be using the alternative meaning.

See https://www.rp-photonics.com/luminous_efficacy_and_efficiency.html where both meanings are described.

-Jon
 
Besoeker3 said:
My two pence worth. We have eight recessed lights in our upstairs bathroom. Four are LED and four are Halogen. How would that figure in terms of efficacy ?
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Eight in your BATHROOM?

I'm putting 6 in a BEDROOM. Are the 4 halogens for heat? Serious question.
 
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