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Good point about the braids, I assumed they should really be outside, hence asking :)
 

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... I measured the temperature of the LEDs and the housing near the braids and it was 95 and 65 respectively...
Ouch! 95 is pretty darn hot - that's the sort of LED temp I was getting when making a high-power LED project about a year ago; I was burning out a few with the thermal runaway I described. I ended up fitting thermistors & reducing the LED power gradually to keep mine below about 60C max. The braids as shown seem to be flat-packed; I assume you've spread them out as far apart as poss. maybe even compressed the braid length-wise to get the strands to expand width-wise & space themselves apart & get max air through? I might even be tempted to fit a diode between the controller & the LEDs just to drop 0.7V and reduce the LED power & so the temperature. It sounds as though these beasts have more than enough lumens as it is! I notice some of these designs have mini built-in fans to cool their heatsinks; I also had a fan to make sure my enclosure stays cool. Mine should arrive this Sunday.
 

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Discussion Starter · #43 ·
@HandyAndy I did exactly as you said regarding the braids, the LEDs are running nicely now whilst I haven't taken a thermometer to them as of yet, once I do I'll let you know,but I can't stress enough on how important they should be outside, just to insure longevity and avoid any issues that could result from overheating.
Stay Safe and happy EV motoring.
 

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I received my Greenclick LED's today.
They are packaged and presented quite well.

I fitted the nearside one first (easiest!).
I tried it and was suitably amazed at the strong light projected on the garage wall.
A great colour too, just the right classic HID shade.

So then I fitted the other one which is a bit more difficult.
I opened out all the braids to dissipate the heat.
I used double sided adhesive pads to stick the ballasts, and tidied up the wires as best I could.
I left the covers off the rear of the lights and made sure the braids didnt touch anything else, which isnt easy as its busy around the lights. I reckoned I would have to think carefully about what I would do about the covers.

Switching on was fantastic, the garage door bathed in blue-white light, with a noticeably different cut-off.
As soon as I hit the road though, I realised there was not as much light on the road overall as the Osram Nightbreaker Unlimited bulbs I fitted a couple of weeks ago. There might just be a little more immediately in front of the car, but further out where you need to see, I am afraid they are lacking.

So I would say they are better than the OEM bulbs, but not as good as the Osrams.
I have now swapped back to the Osrams and they are definitely better. They dont look half as cool, but they are better at lighting up the road, which is what I need them for.

I had high hopes for these, and I am gutted, but there you are. LED's now for sale!
 

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Discussion Starter · #45 · (Edited)
@OLLY Sorry about that, You are probably referring to the throw of the lights, Halogens are known to have a far throw due to the bulb structure, LEDs on the other hand have a very particular directionality and pattern it does not disperse everywhere which makes it very bright within the confinement of the lit area, for me and as per the pictures these make a huge difference and I feel more confident driving at night with them on the car , just return them if you can instead of waiting for a sale maybe ?
I received my Greenclick LED's today.
They are packaged and presented quite well.

I fitted the nearside one first (easiest!).
I tried it and was suitably amazed at the strong light projected on the garage wall.
A great colour too, just the right classic HID shade.

So then I fitted the other one which is a bit more difficult.
I opened out all the braids to dissipate the heat.
I used double sided adhesive pads to stick the ballasts, and tidied up the wires as best I could.
I left the covers off the rear of the lights and made sure the braids didnt touch anything else, which isnt easy as its busy around the lights. I reckoned I would have to think carefully about what I would do about the covers.

Switching on was fantastic, the garage door bathed in blue-white light, with a noticeably different cut-off.
As soon as I hit the road though, I realised there was not as much light on the road overall as the Osram Nightbreaker Unlimited bulbs I fitted a couple of weeks ago. There might just be a little more immediately in front of the car, but further out where you need to see, I am afraid they are lacking.

So I would say they are better than the OEM bulbs, but not as good as the Osrams.
I have now swapped back to the Osrams and they are definitely better. They dont look half as cool, but they are better at lighting up the road, which is what I need them for.

I had high hopes for these, and I am gutted, but there you are. LED's now for sale!
 

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@Chronos please no need for apologies. I have wanted to try an LED for a long time. I completely agree with you that they are better than the standard bulbs.

However I have also tried the Nightbreaker Unlimited 9006 recommended by @HandyAndy and they are better still for night driving.

I now have all 3 sets of bulbs so I am able to do comparisons.

I really wanted these LEDs to be the best. Indeed if the LEDs had been just nearly as good as the Nightbreakers I would use them for their fantastic appearance.

But sadly they are not.

I think I will now order some HIDs to see if they can beat the Nightbreakers!
 

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I have 33 watt HIDs in from HIDS4U at the moment which I am very happy with and will do a comparison test with the LED's at some point.

My LED's have just arrived and are surprisingly much different from having a "bulb" as they have a soft silicon "lens" stuck over the LED chips which are free to touch.
Just by looking at them you can see that the point of light will not be the same as halogen or HIDs as they tend to be in the centre but the LED is either side of a 5mm thick spacer, probably due to the heat sink required behind the chips.

The "lens" isn't moulded either as one is slightly misshapen which can't help the eventual beam. They look as if they have been accurately placed on to the chip but rather as though a bit of silicon was dropped into place.
Knowing China it probably was.

Apart from that they look well made although the connecting plug/socket to the bulb has very tiny pins. You wouldn't think you could get enough power down them to have light and heat to dissipate.

The listed specifications have a comparison between Halogen, HID and LED and the HID has a slightly higher lumen output but with a 5 second start time compared to the LED of zero despite the features list saying the LED lamps are brighter!
Running temp is listed as being 100C compared to 500C for HID but the surprise is that they say these lamps have a 50,000 hour life compared to 3,000 for HID and 800 for halogen.
Really?
Literally, only time will tell.
 

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My "Car Rover® 40W*2 9012 LED Headlight Bulbs 4800LM*2 Conversion Kit 6000k Hid Halogen Replacement Kit 12-24V with Cree LED XHP-50 Chip" from Amazon arrived. Being inquisitive, I've researched the chip spec. The XHP-50 can be wired for 6V or 12V, looking closely there are actually 4 small LEDs inside it, and these white LEDs usually run at about 3.2V, so that makes sense.

So a single LED is rated at max 6V 3A or 12V 1.5A depending how it's wired. That's 18W max either way.
But the more typical values as shown in curves in data-sheet are likely to be around 6V 1400mA or 12V 700 mA.
At these (sensible) values the light output ranges from 105% of nominal at 25C, down to 100% at 85C and 80% at 150C.
6V 1400 mA is 8.4W power used.

The 6000K colour-temp LEDs vary from 730 to 1120 lumens at 85 degrees C, depending on the quality (how the phosphor was made etc). Range is 837 to 1284 at 25C, but we know these are running pretty hot, much closer to 85C than 25.

I've connected one to my variable voltage PSU & cranked it up, measuring the voltage & current across the driver supply, and the voltage and current at the output of the driver circuit, where it goes into the LEDs.

Once the voltage gets to 5V, the lamp starts lighting up, and gets brighter as I raise the input voltage.
The LED supply stabilises at 6.4V 3.1A so the lamp's drawing 19.85W.
I can crank the psu volts up as far as I like, it draws about 3.5A at 8V and 2.06A at 12V so that's 24W.

Ok, time to do some stress-testing. Using my trusty IR thermometer I can point at various bits to see the temp.
Lamp is held in free air in a rubber vice, with the braids fanned-out as wide as poss to get best cooling.
Ambient temp is 19C.

A few moments after power on I have:
LED_Volts LED_amps LED_temp Braid-temp Driver_temp
6.38V 3.17A 85C 20C 20C

after a a few minutes this has changed to
6.24V 3.13A 96C 45C 48C

Time to stress it a bit, so I apply my hot-air paintstripper gun to the end of the braid to raise that to 60C.
After a minute of getting braid nicely warmed, I have
6.17V 3.12A 115C 60C 53C

and leave it to cool down a bit, a couple of minutes later I have
6.19V 3.12A 109C 35C 57C

Throughout all this the driver supply is pretty constant at 24W near as dammit. It looks like the driver is a current-limiting circuit, or just maybe a power-limiting one.

Conclusion: the driver's getting fairly warm on the outside, I'll probably try to glue/clamp a large heatsink to it. The chips on the inside will appreciate being a bit cooler if poss! These buck regulators usually have a capacitor on their output, typically 300 microfarads or thereabouts, and if it's an electrolytic (v likely!) these do not like high temperatures, and rarely have a lifespan of over 7000 hours at best. So the cooler the better for them. The items inside the driver have been epoxied in, so I can't see what the circuit they're using is, sadly.

The LEDs seem to be happy to run at around 110C, they're specced up to 150, so I don't have too many worries about them, provided I can keep them well ventilated when in the car.

I'll put these in the car tonight & have a play.

The front cover of installation booklet.
upload_2016-10-21_17-21-45.jpeg



Piccy inside with details:
upload_2016-10-21_17-22-37.jpeg


Contents of the box:
upload_2016-10-21_17-23-0.jpeg
 

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Discussion Starter · #49 ·
Ahhhh, an Engineer's review is always so delightfully satisfying !! (y)(y):rolleyes::rolleyes: Love it, Best of Luck @HandyAndy
I gave my car the weekly wash and wax session today, vacuumed and cleaned the interior and then I took her to Formula One Autocentre for headlight alignment and they were so happy seeing an Ampera, the staff gathered around and started asking me questions and checking the insides :D.
The headlights weren't too far off if any at all, the MOT technician who performed the alignment said he will take them up a bit because they were aimed downwards on the allowable range and could be pointed up few degrees which he did and they refused to charge me anything at all.

My "Car Rover® 40W*2 9012 LED Headlight Bulbs 4800LM*2 Conversion Kit 6000k Hid Halogen Replacement Kit 12-24V with Cree LED XHP-50 Chip" from Amazon arrived. Being inquisitive, I've researched the chip spec. The XHP-50 can be wired for 6V or 12V, looking closely there are actually 4 small LEDs inside it, and these white LEDs usually run at about 3.2V, so that makes sense.

So a single LED is rated at max 6V 3A or 12V 1.5A depending how it's wired. That's 18W max either way.
But the more typical values as shown in curves in data-sheet are likely to be around 6V 1400mA or 12V 700 mA.
At these (sensible) values the light output ranges from 105% of nominal at 25C, down to 100% at 85C and 80% at 150C.
6V 1400 mA is 8.4W power used.

The 6000K colour-temp LEDs vary from 730 to 1120 lumens at 85 degrees C, depending on the quality (how the phosphor was made etc). Range is 837 to 1284 at 25C, but we know these are running pretty hot, much closer to 85C than 25.

I've connected one to my variable voltage PSU & cranked it up, measuring the voltage & current across the driver supply, and the voltage and current at the output of the driver circuit, where it goes into the LEDs.

Once the voltage gets to 5V, the lamp starts lighting up, and gets brighter as I raise the input voltage.
The LED supply stabilises at 6.4V 3.1A so the lamp's drawing 19.85W.
I can crank the psu volts up as far as I like, it draws about 3.5A at 8V and 2.06A at 12V so that's 24W.

Ok, time to do some stress-testing. Using my trusty IR thermometer I can point at various bits to see the temp.
Lamp is held in free air in a rubber vice, with the braids fanned-out as wide as poss to get best cooling.
Ambient temp is 19C.

A few moments after power on I have:
LED_Volts LED_amps LED_temp Braid-temp Driver_temp
6.38V 3.17A 85C 20C 20C

after a a few minutes this has changed to
6.24V 3.13A 96C 45C 48C

Time to stress it a bit, so I apply my hot-air paintstripper gun to the end of the braid to raise that to 60C.
After a minute of getting braid nicely warmed, I have
6.17V 3.12A 115C 60C 53C

and leave it to cool down a bit, a couple of minutes later I have
6.19V 3.12A 109C 35C 57C

Throughout all this the driver supply is pretty constant at 24W near as dammit. It looks like the driver is a current-limiting circuit, or just maybe a power-limiting one.

Conclusion: the driver's getting fairly warm on the outside, I'll probably try to glue/clamp a large heatsink to it. The chips on the inside will appreciate being a bit cooler if poss! These buck regulators usually have a capacitor on their output, typically 300 microfarads or thereabouts, and if it's an electrolytic (v likely!) these do not like high temperatures, and rarely have a lifespan of over 7000 hours at best. So the cooler the better for them. The items inside the driver have been epoxied in, so I can't see what the circuit they're using is, sadly.

The LEDs seem to be happy to run at around 110C, they're specced up to 150, so I don't have too many worries about them, provided I can keep them well ventilated when in the car.

I'll put these in the car tonight & have a play.
 

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Discussion Starter · #50 · (Edited)
@OLLY The problem with HID is the hassle associated with retro fitting the kit , whether it's locating the ballast, the interference that might occur due to the nature of operation or the uncontrolled glare due to being so powerful, however I can only wish you the best of luck mate.
@Chronos please no need for apologies. I have wanted to try an LED for a long time. I completely agree with you that they are better than the standard bulbs.

However I have also tried the Nightbreaker Unlimited 9006 recommended by @HandyAndy and they are better still for night driving.

I now have all 3 sets of bulbs so I am able to do comparisons.

I really wanted these LEDs to be the best. Indeed if the LEDs had been just nearly as good as the Nightbreakers I would use them for their fantastic appearance.

But sadly they are not.

I think I will now order some HIDs to see if they can beat the Nightbreakers!
 

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Ok guys, just been out for a test. Photos taken out on the road were on Manual setting for consistency. Viewing back on the computer they were all pretty dim, so I've applied a gamma of 2 to brighten up the mid-range while keeping blacks black & whites white. The computer monitor you view these on will have it's own gamma, and a different colour hue to mine, so all you can really do is make the best visual comparison you can. The bulbs are Osram Nightbreakers (the yellowy ones, 2x55W =110W power consumption from battery), and the 6000K LED ones (blueish, 2x24 = 48W battery consumption. If nothing else, these are worth a few more metres on the battery!!!)

Fitting was straightforward, a bit of a mince with the drivers-side one, but so is the Osram. I'm not entirely happy with the space there for the braids, but it will have to do. On the passenger side, there's an earthing strap, so I measured the voltage between the braids and that strap - it's 0.1V . What this means I have no idea, but probably a good idea to put some insulation around that earthing strap just to minimise chances of any tiny sparking/interference. I expect the LED braid is isolated, so this voltage is just noise/pickup, but can't be 100% sure. There's plenty of space for the driver modules, and I'll sort some heatsinks for these.

I didn't refit the large flat caps over the lamp-housing as the braids are in the way, and I want max ventilation! Also didn't fit the rubbery grommet-things which came with the kit.
I might make a 3D-printed replacement cap which would have a hole in the middle to take these grommets - anyone interested, PM me about it. Should be easy to make something...

Beam elevation was pretty good, gave it one click on the adjuster to fine-tune it.

A later append will show the LED lights aimed at gge door, am only allowed 6 in 1 append!

These pics all taken at f3.2, 2 secs exposure, post-processed with gamma=2. The first 4 are reduced resolution, the last 2 are full-resolution cropped down.
I drove home to change the bulbs between takes so car was parked in v slightly different position, but within about 3 feet I'd guess. Near as dammit the identical spot. It's a flat country lane.

Pic 1: Osrams Dipped beam:
upload_2016-10-21_21-10-34.jpeg



Pic 2: LED Dipped beam:
upload_2016-10-21_21-11-7.jpeg



Pic 3: Osrams Main beam:
upload_2016-10-21_21-11-35.jpeg


Pic 4: LEDs Main beam:
upload_2016-10-21_21-12-1.jpeg


Pic 5: Central section cropped from Osrams Main beam pic:
upload_2016-10-21_21-17-51.jpeg



Pic 6: Central section cropped from LEDs Main beam pic:
upload_2016-10-21_21-18-57.jpeg


I did a little trip to see how they worked in traffic etc. My conclusions are that they're a considerable improvement over Osram Nightbreakers.

1) The dip-beam cut-off is fine. It's sharp, see garage pic coming in my next append, and there was no dazzling of on-coming vehicles or cyclists.

2) The blueish hue isn't a problem - reminds me of driving in winter with snow around! But a yellower tone would be better I think. 3000K or 4000K would be a nicer colour temperature, but you get fewer lumens out with yellower phosphors. I may well experiment with a yellow filter.

3) In particular, I have far better vision of where the LHS verge is when traffic's coming the other way. To me, this is the most important thing - I must know where I am. You can see from the top 2 pics how much clearer the verge on the left is.

4) Distance vision straight-ahead is just a fraction less than with the Osrams, but there's very little in it. You can see a tiny bit more of the bend beyond the shed with the Osrams, see pics 5 & 6.

5) Distance vision "all-round" is much better with the LEDs. In particular, note how the LEDs pick out the overhanging tree just above the shed - invisible with Osrams.See pics 3 & 4, also 5 & 6. There's none of that slight patterning of dark-bars the Osrams (& OEM bulbs) give - I'd say the LEDs provide a much more uniform illumination all-over, and when the car's bouncing up & down on a bumpy lane, there's far less flickering effect, and it's just much easier to see what's going on.

So as far as I'm concerned, these are without doubt a safer bulb to use, so I'm sticking with them for now. A big thank-you to Chronos for daring to try these & bringing them to my notice!
 

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Follow-on append with garage doors illuminated by LED bulbs.
upload_2016-10-21_21-45-28.jpeg


No gamma applied to this image, and I think it's a 1/2 second exposure but who cares. I took several & this is the clearest. In particular, note the fairly bright bit of hedge to the left; I think that's my fresnel lens doing it's job!
Garage is down a slight slope from where the car is positioned, and pic is taken from just below the rear-view mirror.
 

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Discussion Starter · #53 · (Edited)
@HandyAndy Marvelous !! I think the future will bring more to the LED scene.
Regarding the dust cover, I got my trusty rotary tool and I drilled a hole in the cap measuring a diameter between 29-31mm and I used a rubber grommet through which I threaded the braids creating a water tight seal around the edges just to prevent any seepage in case of an occasional condensation but most importantly to keep the spiders and dust from getting into the housing. I am waiting for bigger grommets to refine the fitment.
If you would like to get the hole diameter right, I suggest using a spade drill/ flat head bit as it will yield a uniform circular shape which will hold the grommet better and create a tighter seal.
Just use a grinder or rotary tool with a sanding bit attached to grind down the lip then drill the hole as mentioned above.
I am really happy to see this working for you, I am even happier to know I was able to help a fellow Ampera owner drive in safer conditions.
If you can take your car to someone who's got the headlights alignment device they can possibly raise your headlight a degree or 2 within the acceptable safe range much like they did to mine today, it might offer a slightly further throw improving the vision field even more.
 

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Chronos, v brave of you to drill out your only dust-caps! If these LEDs fail early, or I end up replaceing with Osrams again, I want mine to be intact! So I'll just make myself a chinese copy on my ABS printer, and let the software make the hole for me! Good point about spiders - hadn't considered them! I was more worried about damp affecting any reflector there might be in there...
 

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Discussion Starter · #55 ·
Trust me when I say I do regret drilling them now, but even if I go back to Halogens blanking caps will do, at some point I did want to build my own 3D printer in fact I designed the main carriages for the X and Y axis on the CAD software and was going to have them printed out but I got carried away with work and studies and it never saw day's light, I am tempted to do that now.
Meanwhile back to the headlights, I'll find spare covers on eBay UK or US
 

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In practice I think you'll find that TECs are rather inefficient at moving significant amounts of heat (~60% of the electrical power going into even the most efficient white LED will come out as heat) across significant thermal gradients (tens of degrees). You're likely to find you're pouring much more power into the TEC than the LED, this also needs dissipating...
Heat pipes on the other hand ;)
 

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If by TEC you mean ThermoElectric Cooler, aka Peltier-effect devide, forget it for this app. Horrendously inefficient - not the correct beast. The heat dissipated in these lamps isn't that huge - 20 watts - so best is to get decent ventilation to the braids.
If you want to build a 3D printer, you can do worse than the Ultimaker kit- these are pretty open-source & v modifiable. I have an early one, and by now looks bizarre compared to original! The rubber-belt drive systems most of these printers use are rather poor (elastic & imprecise), so I re-engineered mine to use high-pitch leadscrews with plastic nuts instead. PM me if interested in details.
 

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Fascinating thread everyone, particularly the geeky engineer stuff which is right up my street :) Ultimaker 3 has just come out, by the way...
 
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