Previous in Forum: Controlling of Peltier Caliberator   Next in Forum: What Causes Under Voltage on Over Head Lines?
Close

Comments Format:






Change Mode
Close

Subscribe to Discussion:

CR4 allows you to "subscribe" to a discussion
so that you can be notified of new comments to
the discussion via email.

Close

Rating Vote:







Add Vote
6 comments
Rate Comments: Nested
Anonymous Poster

Calculate Lux from Lumens

01/18/2011 6:28 AM

How to calculate lux from lumens
Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

"Almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!
redfred
Guru
Engineering Fields - Electrical Engineering - Been there, done that. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 15600
Good Answers: 981
#1

Re: Calculate Lux from Lumen

01/18/2011 7:12 AM

I believe you will find that area has an important factor. Since lumen is already a unit that reflects the human eye's sensitivity, no weighting for spectral quality need be applied. This though is a very fundamental lighting question that can easily be considered as homework.

So I've given you a very big hint. Now go do the work yourself.

(All puns intended.)

__________________
 "Don't disturb my circles." translation of Archimedes last words
Reply
hithuanand
Power-User
India - Member - New Member Engineering Fields - Electrical Engineering - New Member

Join Date: Apr 2010
Location: Asia/India
Posts: 365
Good Answers: 1
#2

Re: Calculate Lux from Lumen's

01/18/2011 7:55 AM

Total flux required = [(lm/m^2) x Area]/[Coeff. of utilisation x depreciation factor]

or

ø=EA/ηp
Reply
NotUrOrdinaryJoe
Guru
Popular Science - Cosmology - New Member Technical Fields - Technical Writing - New Member Engineering Fields - Energy Engineering - New Member Engineering Fields - Electrical Engineering - New Member Engineering Fields - Control Engineering - New Member Engineering Fields - Electromechanical Engineering - Old Member, New Association

Join Date: Apr 2008
Location: Lexington, KY
Posts: 1639
Good Answers: 73
#3

Re: Calculate Lux from Lumens

01/18/2011 9:48 AM

•A Lumen is a measure of the light flux per some reference area.

• Total lumens refers to the total amount of power (in the form of light) that is emitted.

•Foot-Candle numbers refers to the apparent level of light at some distance from a source.

__________________
 A great troubleshooting tip...."When you eliminate the impossible, whatever remains, however improbable, must be the truth." Sir Arthur Conan Doyle
Reply Score 1 for Good Answer
No more "Almost" Good Answers.
Usbport
Guru
Engineering Fields - Optical Engineering - Member Engineering Fields - Engineering Physics - Member Engineering Fields - Systems Engineering - Member

Join Date: Apr 2010
Location: Trantor
Posts: 5363
Good Answers: 647
#4
In reply to #3

Re: Calculate Lux from Lumens

01/18/2011 2:53 PM

GA. I'd just add that 1 foot-candle is equal to 10.764 lux.

Or, more simply, define a lux as one lumen falling on a surface of 1 square meter.

__________________
 Whiskey, women -- and astrophysics. Because sometimes a problem can't be solved with just whiskey and women.
Reply
msamad
Guru

Join Date: Feb 2009
Location: Houston, USA
Posts: 946
Good Answers: 244
#5

Re: Calculate Lux from Lumens

01/18/2011 6:57 PM

This thread may help:

http://cr4.globalspec.com/thread/60846/Calculation-of-Lumens

- MS

__________________
 "All my technical advices in this forum must be consulted with and approved by a local registered professional engineer before implementation" - Mohammed Samad (Linkedin Profile: http://www.linkedin.com/in/msamad)
Reply
redfred
Guru
Engineering Fields - Electrical Engineering - Been there, done that. Engineering Fields - Control Engineering - New Member

Join Date: Dec 2008
Location: Long Island NY
Posts: 15600
Good Answers: 981
#6
In reply to #5

Re: Calculate Lux from Lumens

01/18/2011 9:35 PM

No no, not another link within CR4. That implies that the OP was just too lazy to use the "Search all of CR4" option on the right hand side of the page. Then again, the OP was too lazy to use Google, Lycos, Yahoo, any public library, or any university resource to look up this simple homework question. I guess that lumps us in with a few prestigious groups. That can't be too bad.

__________________
 "Don't disturb my circles." translation of Archimedes last words
Reply Off Topic (Score 6)
Reply to Forum Thread
Have a Different Question?
6 comments

"Almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!
Copy to Clipboard

Users who posted comments:

hithuanand (1); msamad (1); NotUrOrdinaryJoe (1); redfred (2); Usbport (1)

Previous in Forum: Controlling of Peltier Caliberator   Next in Forum: What Causes Under Voltage on Over Head Lines?
You might be interested in: Lux Meters (Light Meters), Video Cameras, CCD Cameras

Advertisement

Got Something to Say?
Ask a Question
Start a Discussion

Search this Forum
Electrical Engineering:
Go

CR4 Sections
Aerospace
BioMech & BioMed
Chemical & Material Science
Civil Engineering
Communications & Electronics
Education and Engineering Careers
Electrical Engineering
General Discussion
Instrumentation
Manufacturing
Mechanical Engineering
New Technologies & Research
Software & Programming
Sustainable Engineering
Transportation

Site Directories
Forum Directory
Blog Directory
User Group Directory
RSS Feeds

CR4 Rules of Conduct
CR4 FAQ
Site Glossary

Who's Online (167 right now)
Show Members
Advertisement