BTU's of a HPL 575

[eqrunner]

Does anyone know what the BTU (British Thermal Units) is on a standard HPL 575w Lamp used in Source4 Lekos/pars?

I need to calculate the heat output of my fixtures in BTU rating.

I have seen the equasion (V * I) * 3.142 = BTU, but that number seams to come out way to high.
[(Volts * Current[Amps]) * 3.142 ]

 

[sk8rsdad]

1963 BTU per hour, or with more detail and dubious precision, 1963.28 BTU per hour. Of course, all of this presupposes you operate the instrument at it's rated output, continuously.

 

[eqrunner]

Awesome thanks.

 

[eqrunner]

I happened to find this info from ETC. Good reference info to have:
KnowledgeBase: Source Four Heat Ratings/ How Much Heat Does the Source 4 Emit? - Electronic Theatre Controls

Typical Heat Dissipation of ETC Fixtures (All measurements are BTUs per Hour)

Fixture: Source Four 750w
Projected Light Beam: 230
Fixture Housing Dissipated: 2330
Total: 2560

Fixture: Source Four 575w
Projected Light Beam: 180
Fixture Housing Dissipated: 1780
Total: 1960

Fixture: Source Four PAR EA 750w
Projected Light Beam: 1150
Fixture Housing Dissipated: 1410
Total: 2560

Fixture: Source Four PAR EA 575w
Projected Light Beam: 880
Fixture Housing Dissipated: 1080
Total: 1960

Fixture: Source Four PAR MCM 575w
Projected Light Beam: 145
Fixture Housing Dissipated: 1815
Total: 1960

Fixture: Source Four HID 150w
Projected Light Beam: (not available)
Fixture Housing Dissipated: (not available)
Total: 513

Fixture: PAR 64 1000w
Projected Light Beam: ~1100
Fixture Housing Dissipated: ~2314
Total: 3414

Fixture: Fresnel 2000w
Projected Light Beam: (not available)
Fixture Housing Dissipated: (not available)
Total: 6828

 

[sk8rsdad]

If you notice, the links in my response point to the article you happened to find.

 

[TJCornish]

Does anyone know what the BTU (British Thermal Units) is on a standard HPL 575w Lamp used in Source4 Lekos/pars?

I need to calculate the heat output of my fixtures in BTU rating.

I have seen the equasion (V * I) * 3.142 = BTU, but that number seams to come out way to high.
[(Volts * Current[Amps]) * 3.142 ]

Your equation is correct. Simplifying it if you already know the wattage: Watts * 3.14 = BTU (assuming the bulb is actually drawing its stated wattage rating).

This is independent of a specific fixture - watts are watts.

What IS different between fixtures is where the heat is radiated. Source 4s have a very cool beam, meaning most of the heat is emitted out of the housing of the fixture. More conventional fixtures that reflect the IR output from the bulb down the beam radiate a lower percentage of their heat at the fixture, and a higher percentage at the point of illumination.