Why no interest in LED headlamps?
02-18-2015, 01:43 PM
#64
Drifting
Yes the journey was in my 928 S4 1988 and of course the lights stick up in the airflow. Just the same as in your 964 the air passes over the lens and hits the front of the car.
These lights do not generate heat like standard Halogen bulbs.
No, they don't, but halogen bulbs can easily withstand the heat they generate, even with HEAT trapped inside the bucket.
However, the silicon chips that constitute LEDs once processed are very much subject to failure from HEAT. "insulation" breaks down and current avalanche melts the silicon.
So for example on many TIPEC evenings on the car park showing my lights to fellow members you can feel the std Halogen bulbs heating up the headlight glass so much that it almost burns your hands to the touch. Whilst the CREE LED headlights generate NO heat and the front headlight glass remains cold!
"Generate no heat..", Pure BS, shows a complete lack of understanding of the product.
When you drive your car the oncoming air cools your glass headlight so as to dissipate the heat generated from using Standard Halogen bulbs as they give off excessive heat. Our CREE LED bulbs DO NOT generate the heat output to the front of the headlight glass.
Agreed, the heat must be "wicked away" long before it begins to affect the contained atmosphere inside the headlight.
That is the difference between CREE LED bulbs versus Halogen bulbs or HID.
The bulbs has a fan at the base of the aluminium and copper core which allows the very efficient cooling of the bulb core which acts as a heatsink for the bulb. just like computer chips etc. sit on heatsinks.
I would question just how efficient the heat conductivity from the LED chip to the fan/heatsink might be but the answer lies in the fact you have circuitry to automatically DERATE the LED brightness when/if the heat rises to high.
If I had even the slightest expectation of such an event I would NEVER use your LEDs as the primary source of night vision.
Our CREE LED bulbs are fitted to many different makes of cars, some have very airtight cavities behind the bulb and others don't. We do not see this making any difference to the performance or lifecycle of our bulbs!
Then why do you use an automatic LED derating circuit.??
All cars, especially your 964's and 944 and our 929's have body seems that let air move around our car. I cannot see OBVIOUSLY...!!!this being any different to every other car on the roads including 911's which have our bulbs fitted.
Let me know if you have any other questions.
When I get the photos from the 964 customers in the UK I will post them.
Thanks
Steve
These lights do not generate heat like standard Halogen bulbs.
No, they don't, but halogen bulbs can easily withstand the heat they generate, even with HEAT trapped inside the bucket.
However, the silicon chips that constitute LEDs once processed are very much subject to failure from HEAT. "insulation" breaks down and current avalanche melts the silicon.
So for example on many TIPEC evenings on the car park showing my lights to fellow members you can feel the std Halogen bulbs heating up the headlight glass so much that it almost burns your hands to the touch. Whilst the CREE LED headlights generate NO heat and the front headlight glass remains cold!
"Generate no heat..", Pure BS, shows a complete lack of understanding of the product.
When you drive your car the oncoming air cools your glass headlight so as to dissipate the heat generated from using Standard Halogen bulbs as they give off excessive heat. Our CREE LED bulbs DO NOT generate the heat output to the front of the headlight glass.
Agreed, the heat must be "wicked away" long before it begins to affect the contained atmosphere inside the headlight.
That is the difference between CREE LED bulbs versus Halogen bulbs or HID.
The bulbs has a fan at the base of the aluminium and copper core which allows the very efficient cooling of the bulb core which acts as a heatsink for the bulb. just like computer chips etc. sit on heatsinks.
I would question just how efficient the heat conductivity from the LED chip to the fan/heatsink might be but the answer lies in the fact you have circuitry to automatically DERATE the LED brightness when/if the heat rises to high.
If I had even the slightest expectation of such an event I would NEVER use your LEDs as the primary source of night vision.
Our CREE LED bulbs are fitted to many different makes of cars, some have very airtight cavities behind the bulb and others don't. We do not see this making any difference to the performance or lifecycle of our bulbs!
Then why do you use an automatic LED derating circuit.??
All cars, especially your 964's and 944 and our 929's have body seems that let air move around our car. I cannot see OBVIOUSLY...!!!this being any different to every other car on the roads including 911's which have our bulbs fitted.
Let me know if you have any other questions.
When I get the photos from the 964 customers in the UK I will post them.
Thanks
Steve
And: Mounting the HEAT generating external regulator inside the headlight bucket as you show in the picture seems to me to be the ultimate in stupidity, probably arising from an almost total lack of knowledge, understanding, of overall design needs of LED lighting.
Have you given any consideration to/of 20Khz PWM dutycycle modulation of the power to the LED?
Most CREE LEDs can be overdriven by 150% with the appropriate dutycycle reduction. Plus that might be a better way to DERATE the power to the LED in case of overheating, drop the dutycycle from 75% to 50%, the LED remains at full brightness 50% of the time and at 20Khz the human eye doesn't notice.
02-18-2015, 02:06 PM
#65
Drifting
Absolutely Not!
PURE BS...!!! Dropping the power to the LED to retard the rate of rise of the heat level will ALWAYS result in less forward vision.
The fan keeps the temperature of the heatsink base controlled under normal operating conditions. Only if the fan were to fail the current would drop as a safety feature. We have not had any fans fail so this has not been an issue.
PURE BS...!!! Dropping the power to the LED to retard the rate of rise of the heat level will ALWAYS result in less forward vision.
The fan keeps the temperature of the heatsink base controlled under normal operating conditions. Only if the fan were to fail the current would drop as a safety feature. We have not had any fans fail so this has not been an issue.
"We have not had any fans fail..." They will, and I can say that with absolute certainty. The PM on our enterprise/server class PC systems involves checking the operation of the brushless/ball bearing cooling fans on a regular basis. Stop the fan manually, if it doesn't restart it gets replaced.
Higher level of component stocking in our spares.
How is the "shift" from low beam to high beam accomplished?
Pictures of both modes against a white wall at a 15-20 foot distance would be extremely helpful.
02-19-2015, 01:31 AM
#66
Burning Brakes
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For anyone interested in the UK I have been speaking to Steve from Woodypeck and he is putting together a few different sets of LED's for me to try and I will provide installation photos and so on for the community, hopefully after the weekend.
Not wishing to get involved in another Loren'esque debate but, there are other lamps on the market for sure, but I wanted something I knew would fit and a bit more tried and tested - it has at least been used by the 928 / 944 crowd for a while. This is relatively new technology and I am sure these will continue to be developed and get better over the coming years. For me, right now, I'm happy to go with something knowing newish technology is likely to change quickly to get the benefit now.
Not wishing to get involved in another Loren'esque debate but, there are other lamps on the market for sure, but I wanted something I knew would fit and a bit more tried and tested - it has at least been used by the 928 / 944 crowd for a while. This is relatively new technology and I am sure these will continue to be developed and get better over the coming years. For me, right now, I'm happy to go with something knowing newish technology is likely to change quickly to get the benefit now.
02-19-2015, 05:02 AM
#67
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Another point, two actually. That external module seems extraordinarily large for a reasonably efficient PWM current injection module, is that by chance a linear regulator?
And: Mounting the HEAT generating external regulator inside the headlight bucket as you show in the picture seems to me to be the ultimate in stupidity, probably arising from an almost total lack of knowledge, understanding, of overall design needs of LED lighting.
Have you given any consideration to/of 20Khz PWM dutycycle modulation of the power to the LED?
Most CREE LEDs can be overdriven by 150% with the appropriate dutycycle reduction. Plus that might be a better way to DERATE the power to the LED in case of overheating, drop the dutycycle from 75% to 50%, the LED remains at full brightness 50% of the time and at 20Khz the human eye doesn't notice.
And: Mounting the HEAT generating external regulator inside the headlight bucket as you show in the picture seems to me to be the ultimate in stupidity, probably arising from an almost total lack of knowledge, understanding, of overall design needs of LED lighting.
Have you given any consideration to/of 20Khz PWM dutycycle modulation of the power to the LED?
Most CREE LEDs can be overdriven by 150% with the appropriate dutycycle reduction. Plus that might be a better way to DERATE the power to the LED in case of overheating, drop the dutycycle from 75% to 50%, the LED remains at full brightness 50% of the time and at 20Khz the human eye doesn't notice.
02-19-2015, 05:59 AM
#68
Is it really necessary to launch into an unprovoked and scathing attack on someone trying to put forward a new technology? Sure, say you disagree, and suggest better alternatives, but to storm in and start using inflammatory language is quite uncalled for. The fact that you start quoting random electrical principles and buzzwords makes me doubt your competence on the subject...
02-19-2015, 07:03 AM
#70
Don't get flashed at night. Have had our CREE LED bulbs in my 928 for over 18 months and through 2 MOT tests with no problems and asking the MOT station specifically if they could fail the car with our headlights - and the answer is NO.
02-19-2015, 07:07 AM
#71
[QUOTE=sy0296;12049562]just FYI for those of you impatient like me. after seeing Bizman's posts i searched for "cree h4 led" on amazon and purchased a set of these (no affilication):
amazon prime had them delivered same day as i was eager to try them out. packaged arrived as promise, quality from visual seemed good, and i went to fit them. after having the bulbs in the housing, i was worried they might not fit, and sure enough, they are about an inch too long with the heatsink/fan housing. i turned them on anyways and they are much brighter than halogen bulbs but was unable to check the cut off
not sure if Bizman's have these large heatsink/fan units on the back of the bulb, but if it's a similar design, you'll need cut into the fenders to have these fit
i have these on order and they'll arrive sometime towards the end of the week. will let you guys know if they work out or not
---------------------------------------------------------------------
Hi
These seem to be a cross between both of the bulbs we supply.
The big fan on the back will give you a problem fitting into the cowl of the 911. That is why I have previously never offered them to 911 owners - I regularly test our bulbs at our TIPEC meets in the UK and our bulbs have always been too big.
The latter set you show with the copper tape we have considered stocking. but the bulbs are positioned wrong in our mind - they go from side to side instead of up & down. This would considerably change the "throw" of light" from our consideration and might provide the wrong light pattern on the road. But when you get them please let us know how you get on.
The new 2015 bulbs seem to fit the 964 from the customers who have fitted them so far - although have just spoke with one 964 customer who said he noticed when fitting it just touched the back of the bowl - so he gave some modification of the back of the bowl with a tap hammer - just to give some clearance at the back where the bowl is shaped anyway. Will get photos posted at the weekend.
Many Thanks
Steve
amazon prime had them delivered same day as i was eager to try them out. packaged arrived as promise, quality from visual seemed good, and i went to fit them. after having the bulbs in the housing, i was worried they might not fit, and sure enough, they are about an inch too long with the heatsink/fan housing. i turned them on anyways and they are much brighter than halogen bulbs but was unable to check the cut off
not sure if Bizman's have these large heatsink/fan units on the back of the bulb, but if it's a similar design, you'll need cut into the fenders to have these fit
i have these on order and they'll arrive sometime towards the end of the week. will let you guys know if they work out or not
---------------------------------------------------------------------
Hi
These seem to be a cross between both of the bulbs we supply.
The big fan on the back will give you a problem fitting into the cowl of the 911. That is why I have previously never offered them to 911 owners - I regularly test our bulbs at our TIPEC meets in the UK and our bulbs have always been too big.
The latter set you show with the copper tape we have considered stocking. but the bulbs are positioned wrong in our mind - they go from side to side instead of up & down. This would considerably change the "throw" of light" from our consideration and might provide the wrong light pattern on the road. But when you get them please let us know how you get on.
The new 2015 bulbs seem to fit the 964 from the customers who have fitted them so far - although have just spoke with one 964 customer who said he noticed when fitting it just touched the back of the bowl - so he gave some modification of the back of the bowl with a tap hammer - just to give some clearance at the back where the bowl is shaped anyway. Will get photos posted at the weekend.
Many Thanks
Steve
Last edited by Bizman928; 02-19-2015 at 07:53 AM.
02-19-2015, 12:23 PM
#72
Burning Brakes
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For anyone interested in the UK I have been speaking to Steve from Woodypeck and he is putting together a few different sets of LED's for me to try and I will provide installation photos and so on for the community, hopefully after the weekend.
Not wishing to get involved in another Loren'esque debate but, there are other lamps on the market for sure, but I wanted something I knew would fit and a bit more tried and tested - it has at least been used by the 928 / 944 crowd for a while. This is relatively new technology and I am sure these will continue to be developed and get better over the coming years. For me, right now, I'm happy to go with something knowing newish technology is likely to change quickly to get the benefit now.
Not wishing to get involved in another Loren'esque debate but, there are other lamps on the market for sure, but I wanted something I knew would fit and a bit more tried and tested - it has at least been used by the 928 / 944 crowd for a while. This is relatively new technology and I am sure these will continue to be developed and get better over the coming years. For me, right now, I'm happy to go with something knowing newish technology is likely to change quickly to get the benefit now.
02-19-2015, 02:08 PM
#73
Burning Brakes
02-19-2015, 06:45 PM
#74
Burning Brakes
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Yes, I have been discussing this but Steve wants to ensure fitment on the 964 I think. Hopefully know in a couple of days what works and there will be a full range of tested lamps for other parts too.
02-19-2015, 10:01 PM
#75
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[QUOTE=Bizman928;12051953]
still waiting patiently for your customer's installed photos. i'm not sure if i like the idea of hammering into the body work for some lightbulbs if there are other alternatives though
i'll also post some feedback and photos of those copper tape LEDs and you can decide if you'll want to stock these for your shop. i'm all into trying new things and these LEDs are cheap enough for me to experiment (plus, Amazon's great return policy)
just FYI for those of you impatient like me. after seeing Bizman's posts i searched for "cree h4 led" on amazon and purchased a set of these (no affilication):
amazon prime had them delivered same day as i was eager to try them out. packaged arrived as promise, quality from visual seemed good, and i went to fit them. after having the bulbs in the housing, i was worried they might not fit, and sure enough, they are about an inch too long with the heatsink/fan housing. i turned them on anyways and they are much brighter than halogen bulbs but was unable to check the cut off
not sure if Bizman's have these large heatsink/fan units on the back of the bulb, but if it's a similar design, you'll need cut into the fenders to have these fit
i have these on order and they'll arrive sometime towards the end of the week. will let you guys know if they work out or not
---------------------------------------------------------------------
Hi
These seem to be a cross between both of the bulbs we supply.
The big fan on the back will give you a problem fitting into the cowl of the 911. That is why I have previously never offered them to 911 owners - I regularly test our bulbs at our TIPEC meets in the UK and our bulbs have always been too big.
The latter set you show with the copper tape we have considered stocking. but the bulbs are positioned wrong in our mind - they go from side to side instead of up & down. This would considerably change the "throw" of light" from our consideration and might provide the wrong light pattern on the road. But when you get them please let us know how you get on.
The new 2015 bulbs seem to fit the 964 from the customers who have fitted them so far - although have just spoke with one 964 customer who said he noticed when fitting it just touched the back of the bowl - so he gave some modification of the back of the bowl with a tap hammer - just to give some clearance at the back where the bowl is shaped anyway. Will get photos posted at the weekend.
Many Thanks
Steve
amazon prime had them delivered same day as i was eager to try them out. packaged arrived as promise, quality from visual seemed good, and i went to fit them. after having the bulbs in the housing, i was worried they might not fit, and sure enough, they are about an inch too long with the heatsink/fan housing. i turned them on anyways and they are much brighter than halogen bulbs but was unable to check the cut off
not sure if Bizman's have these large heatsink/fan units on the back of the bulb, but if it's a similar design, you'll need cut into the fenders to have these fit
i have these on order and they'll arrive sometime towards the end of the week. will let you guys know if they work out or not
---------------------------------------------------------------------
Hi
These seem to be a cross between both of the bulbs we supply.
The big fan on the back will give you a problem fitting into the cowl of the 911. That is why I have previously never offered them to 911 owners - I regularly test our bulbs at our TIPEC meets in the UK and our bulbs have always been too big.
The latter set you show with the copper tape we have considered stocking. but the bulbs are positioned wrong in our mind - they go from side to side instead of up & down. This would considerably change the "throw" of light" from our consideration and might provide the wrong light pattern on the road. But when you get them please let us know how you get on.
The new 2015 bulbs seem to fit the 964 from the customers who have fitted them so far - although have just spoke with one 964 customer who said he noticed when fitting it just touched the back of the bowl - so he gave some modification of the back of the bowl with a tap hammer - just to give some clearance at the back where the bowl is shaped anyway. Will get photos posted at the weekend.
Many Thanks
Steve
i'll also post some feedback and photos of those copper tape LEDs and you can decide if you'll want to stock these for your shop. i'm all into trying new things and these LEDs are cheap enough for me to experiment (plus, Amazon's great return policy)