Dash Board Lamps.
Discussion
Does anyone have any idea about how brightness is measured ???
I've been looking for a viable alternative to the standard white light bulb type illumination for the gauges (been driving too many Audi's/VW's) and have found an "ultra bright" LED fitted into the correct type of bayonet BA9s which will plug directly in and is avaliable in red,green,yellow,blue & white however they show their Luminous Intensity for LED's in a unit called "mcd" typical between 300 -1000 while normal bulbs show "nominal lumens" around 11.06. Has anyone the faintest idea how these two compare ???? or basically will the LED's be bright enough to light my gauges ???
I've been looking for a viable alternative to the standard white light bulb type illumination for the gauges (been driving too many Audi's/VW's) and have found an "ultra bright" LED fitted into the correct type of bayonet BA9s which will plug directly in and is avaliable in red,green,yellow,blue & white however they show their Luminous Intensity for LED's in a unit called "mcd" typical between 300 -1000 while normal bulbs show "nominal lumens" around 11.06. Has anyone the faintest idea how these two compare ???? or basically will the LED's be bright enough to light my gauges ???
! Rich... I'm doing this while the dash is out, I took it all out and stripped it down on saturday and must say that I was pleasantly suprised how easy it was after all the horror stories I'd heard, I'm making something very special to go in it's place but that will all come out in few months but includes the change in light colour.
Light output from LEDs is highly directional - see the following example which shows that relatively small movements of the eye away from straight on will show a dramatic reduction in brightness.
Contrast this with the output from a typical incandescant lamp that looks equally bright from which ever direction you view it. It is possible to use lenses or scattering media to broaden the light distribution from the LED, or to mount the LEDs at different angles, to create useful solutions as for example in the new traffic lights and external vehicle lighting applications.
The light output from an LED can be measured in two ways:
(1) the total optical power delivered from the device without regard to the direction in which the energy is emitted - expressed in lumens ; or
(2) the luminous intensity of light that is directed towards the observer - expressed in candela (cd) or millicandela (mcd).
So your question addresses a number of issues. Perhaps the most important issue is directionality of light emitted from LEDs. Just replacing an incandescent bulb in a dashboard instrument or switch with an LED may work in some cases where the projected light from the LED is directly forward toward the observer eg a warning light but might not work without some light dispersion modification behind an instrument.
So the millicandela is the most relevant measure in which to describe the brightness of an LED for the type of applications you have in mind.
Hutch
Contrast this with the output from a typical incandescant lamp that looks equally bright from which ever direction you view it. It is possible to use lenses or scattering media to broaden the light distribution from the LED, or to mount the LEDs at different angles, to create useful solutions as for example in the new traffic lights and external vehicle lighting applications.
The light output from an LED can be measured in two ways:
(1) the total optical power delivered from the device without regard to the direction in which the energy is emitted - expressed in lumens ; or
(2) the luminous intensity of light that is directed towards the observer - expressed in candela (cd) or millicandela (mcd).
So your question addresses a number of issues. Perhaps the most important issue is directionality of light emitted from LEDs. Just replacing an incandescent bulb in a dashboard instrument or switch with an LED may work in some cases where the projected light from the LED is directly forward toward the observer eg a warning light but might not work without some light dispersion modification behind an instrument.
So the millicandela is the most relevant measure in which to describe the brightness of an LED for the type of applications you have in mind.
Hutch
quote:
The LEDs i have sent to Mel are the same as i have used in my dash and they look great and indeed are much brighter than the horid orange glowing bulbs which were in there.
Thanks David, I'll let you all know what my TVR/VW dash looks like when it's all finished (probably 2/3weeks)
I think as with all things TVR it depends on what you've got fitted, in my once I had the dash removed with the clocks still in it the lamps in their holders were simple pushed into a rubber grommet on the back of the relevant gauge, once pulled out the lamp is a bayonet fit in the fitting.
Good luck with the Dash Mel.
David, i have yellow Dials currently in my dash and cant remember but think they had these orange ones in.
What would u recommend changing them to colourwise.
The ones have seem to be quite bright in the larger dials and dimmer in the Small gauges,Fuel etc i know this might not be only due to the colour of the bulb.
BB
David, i have yellow Dials currently in my dash and cant remember but think they had these orange ones in.
What would u recommend changing them to colourwise.
The ones have seem to be quite bright in the larger dials and dimmer in the Small gauges,Fuel etc i know this might not be only due to the colour of the bulb.
BB
David you are a gentleman.
My jiffy bag of bits arrived first class this morning, and has kept me entertained for a while, all I can say is the blue ones are F bright and I'm sure will do the job.
Just a thought maybe you could fit them into washer jets, sell them and make a killing
what an original idea that would be. Seriously if your at BT&P make sure we meet up and I owe you beer.
My jiffy bag of bits arrived first class this morning, and has kept me entertained for a while, all I can say is the blue ones are F bright and I'm sure will do the job.
Just a thought maybe you could fit them into washer jets, sell them and make a killing
what an original idea that would be. Seriously if your at BT&P make sure we meet up and I owe you beer.BB
you can just about get your hand to the clock through the glove box, feeling around you can pop the spade connectors off and remove the bulb socket with bulb. Iam sure it will be just a 5w bulb that just glows orange as it so low wattage. I can send you a white LED for you to try, but you have to be able to feel the connectors back on. I have done it many a time. I realy do not know what other colour will do.
you can just about get your hand to the clock through the glove box, feeling around you can pop the spade connectors off and remove the bulb socket with bulb. Iam sure it will be just a 5w bulb that just glows orange as it so low wattage. I can send you a white LED for you to try, but you have to be able to feel the connectors back on. I have done it many a time. I realy do not know what other colour will do.
I'm thinking about using bright LED's for the dash on the 3000M i'm rebuilding. Apologies if this has already been covered elsewhere, and please point me in the right direction if it has, but besides linking up the LED instead of the bulb, are any other modifications necessary? Are they going to work normally with 12v, or am I going to have to introduce some sort of converter somewhere? The LED's that i've seen on the RS web site, for example, have just two solderable connections - is it as simple as conencting these up, or can you get holders in the same way as you can for bulbs?
Thanks folks,
Tony
www.tvr-3000m.co.uk
Thanks folks,
Tony
www.tvr-3000m.co.uk
Rich sorry
you can only get to the clock bulb through the glove box(electrical latch on mine now!), it was just so BB could see what the white LED would look like in a dial. Not sure as i said about white LED with orange dials. Still, there are car stereos around with white displays, blue buttons with red illumination! I convert some 300 per month back to good old amber.
you can only get to the clock bulb through the glove box(electrical latch on mine now!), it was just so BB could see what the white LED would look like in a dial. Not sure as i said about white LED with orange dials. Still, there are car stereos around with white displays, blue buttons with red illumination! I convert some 300 per month back to good old amber.
Bigtone
you can buy LEDs off the shelf for direct "plug in". They are really quite expensive, £6 around. The best way is to DIY. Take a 12v regulator and a resitor to limit current. The regulator i use is rated at 100ma so only 4 dials can be done per regulator, still they are only 60p ish. You can do it without a voltage regulator, but there is such a large variance depending on voltage it is best.
you can buy LEDs off the shelf for direct "plug in". They are really quite expensive, £6 around. The best way is to DIY. Take a 12v regulator and a resitor to limit current. The regulator i use is rated at 100ma so only 4 dials can be done per regulator, still they are only 60p ish. You can do it without a voltage regulator, but there is such a large variance depending on voltage it is best.
Gassing Station | General TVR Stuff & Gossip | Top of Page | What's New | My Stuff