Alan B
100 GW
Yes, they really missed an opportunity. Fluke would get you $$$ for a special meter fuse. Don't ask me how I know.
Super light ?
- Thread starter mushymelon
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Well, I have a Fluke 287... I know WAY too much about Flukeitudy fuses 
... it has two different current fuses that are custom values 10% over standard values... 12 bucks a pop for the 11A BBS one, 8 bucks for the 440 mA. I usually just us a 10A fuse and call it a 9A meter, and 1/2 amp for the other one.
I also have several Fluke 80xx series meters. They use a 3A BBS fuse and a 2A AGX fuse. I bought a bunch of the BBS ones for dirt cheap. The AGX's are hard to find and expensive. I built little adapters out of brass tubing that plug onto 25 cent 5x20mm fuses. They extend the 20mm out to 25mm.
... it has two different current fuses that are custom values 10% over standard values... 12 bucks a pop for the 11A BBS one, 8 bucks for the 440 mA. I usually just us a 10A fuse and call it a 9A meter, and 1/2 amp for the other one.I also have several Fluke 80xx series meters. They use a 3A BBS fuse and a 2A AGX fuse. I bought a bunch of the BBS ones for dirt cheap. The AGX's are hard to find and expensive. I built little adapters out of brass tubing that plug onto 25 cent 5x20mm fuses. They extend the 20mm out to 25mm.
Alan B
100 GW
Exactly. I have unfortunately found out about some of the Fluke fuses in my older meter. Haven't popped any in my Fluke 189 yet, and hope not to. Trying to be very careful...
Very interesting big LEDs. I have one of the 30+ watt SST90 LED's and a heatsink but have not fired it up yet. I have an SST50 flashlight or two, very nice but I don't think they are driving them fully to 15+ watts. And a bunch of P7's. One of Mac's triple P7's. A bit big for a bike light at about 2.5D M@g size but nice and bright. Probably too floody for a bike light as well.
Very interesting big LEDs. I have one of the 30+ watt SST90 LED's and a heatsink but have not fired it up yet. I have an SST50 flashlight or two, very nice but I don't think they are driving them fully to 15+ watts. And a bunch of P7's. One of Mac's triple P7's. A bit big for a bike light at about 2.5D M@g size but nice and bright. Probably too floody for a bike light as well.
These big LEDs spew around 110-140 degrees without any optics. But then they have the lumens to do it and still be effective. It still lights up the road pretty well 50 yards away, and signs shine back like nobody's business. You can get 14 and 24 degree reflectors for the Bridgelux LEDs. Should make a nice flashlight. I'm thinking of using straight 28V DeWalt tool packs. Maybe mount the head onto their flashlight tool.
The Chinese ones have some aspheric lenses available. I have some 60 degree ones. The resulting beam is a bit blotchy becuase they don't combine the individual led outputs well. They have some "euro-headlight" lenses with the horizontal ridges. Not sure what those would do.
A 1P A123 pack runs the 50 watt leds for about an hour (45 minutes has full output). With the dimmer you get more run time. Dimming it to 1/6 power would match those 900 lumen lights that are still too bright for most people. Keep it at full output and the onlookers get vaporized.
The Chinese ones have some aspheric lenses available. I have some 60 degree ones. The resulting beam is a bit blotchy becuase they don't combine the individual led outputs well. They have some "euro-headlight" lenses with the horizontal ridges. Not sure what those would do.
A 1P A123 pack runs the 50 watt leds for about an hour (45 minutes has full output). With the dimmer you get more run time. Dimming it to 1/6 power would match those 900 lumen lights that are still too bright for most people. Keep it at full output and the onlookers get vaporized.
My idea of boosting the PWM duty cycle as the battery voltage fell was kind of a bust. It worked, but wound up limiting the how low you could dim the light. It basically added a value to the PWM ratio that was dependent upon how much the battery voltage had fallen below a set threshold (like 3.2V per cell).
So I did the opposite thing. I started backing off on the maximum PWM duty cycle when the battery voltage was above like 3.3V per cell. This works much better. It keeps the light output constant as the battery surface charge is depleted. It also helps protect the LED against drawing too much current because its current can increase exponentially once the voltage across it exceeds its forward voltage spec. There is also another level of protection built in. If the battery voltage exceeds a set amount (3.7V/cell) the LED is shut off.
So I did the opposite thing. I started backing off on the maximum PWM duty cycle when the battery voltage was above like 3.3V per cell. This works much better. It keeps the light output constant as the battery surface charge is depleted. It also helps protect the LED against drawing too much current because its current can increase exponentially once the voltage across it exceeds its forward voltage spec. There is also another level of protection built in. If the battery voltage exceeds a set amount (3.7V/cell) the LED is shut off.
I got in those 5000 lumen(@ 54 watts in) Bridgelux LEDs from DigiKey. Bright little mofos... I am pumping 60 watts into one (25.6V, 2.35 amps). I need to compare the light output to the Chinese 50 watt array (at 60W). The spec sheet on the Bridgelux shows parameters up to 4 amps... that would be 110 watts or so and 8500 lumens.
I have it mounted to an AMD processor heat sink. With my 24V/70 mA fan there is no detectable heat rise. I don't have the thermal sensor mounted yet, so I'm running the fan at max (which isn't much)
I also got some 14 and 24 degree reflectors. Should be interesting to see how they perform...
I have it mounted to an AMD processor heat sink. With my 24V/70 mA fan there is no detectable heat rise. I don't have the thermal sensor mounted yet, so I'm running the fan at max (which isn't much)
I also got some 14 and 24 degree reflectors. Should be interesting to see how they perform...
I did a light output test. At 60W in the Chinese LED put out 27,000 lux. The Bridgelux puts out 39,000 lux at the same distance (my lux meter only goes to 40,000 lux). At 36W in the Bridgelux puts out more light than the Chinese thing does at 60 watts.
I got to play with the Bridgelux LED outside, in the dark and woodsy night. I used an 8S1P A123 pack. Its drive requirements are very well matched to that pack. The thing is freaky bright. It is spooky to see an area the size of a quarter fully illuminate a 60 foot tall/wide oak tree or 1000+ square foot side of a two story house, or the yards of three houses.
Don't bother with the 24 degree reflector, get the 14 degree. They specify the angle as a half-angle. The 14 degree reflector makes a 28 degree (at half intensity) wide beam. Without the reflector, the half intensity beam width is 120 degrees.
Did I mention, the thing is freaky bright...
Don't bother with the 24 degree reflector, get the 14 degree. They specify the angle as a half-angle. The 14 degree reflector makes a 28 degree (at half intensity) wide beam. Without the reflector, the half intensity beam width is 120 degrees.
Did I mention, the thing is freaky bright...
I fired up the 100 watt Chinese LED (supposedly 8000 lumens). At 100 watts in, it puts out almost exactly the same amount of light as the Bridgelux does at 60 watts.
I want to see how small a heatsink you actually need when using a cooling fan. I suspect that my heatsinks are way too big. The Bridgelux is spec'd at 105C max case temperature. With my wimpy fan running with a very conservative PWM ratio from the temp sensor, the thing is running around 33C. With the fan on full, it does not have any temperature rise. It may not need any heatsink with a more aggressive fan control profile.
I want to see how small a heatsink you actually need when using a cooling fan. I suspect that my heatsinks are way too big. The Bridgelux is spec'd at 105C max case temperature. With my wimpy fan running with a very conservative PWM ratio from the temp sensor, the thing is running around 33C. With the fan on full, it does not have any temperature rise. It may not need any heatsink with a more aggressive fan control profile.
Personally I'm all for heatsinks that are just large enough to prevent instant component death if the fan should fail without warning. 
Well, some kind of heat sink is definitely needed... I tried the 50W Chinese LED with just a screaming meanie little 40 mm fan blowing on the back of it. It hits 160F in around 1 minute. I have a couple of small heatsinks that fit the back of the LED perfectly that I can try... if I can get the LED mounted to them. One has some thermal tape so that could be easy (but thermal tape sucks)
Well, with a small (2 x 2 x 0.375 inch) heatsink and a lot of airflow you can cool these things down to manageable levels... barely... borderline impractical. At 60 watts in to the Chinese LED and using the tiny 40mm screamin' meanie fan (REALLY obnoxious) it reaches thermal equilibrium about 90F above ambient.
I think a cut down CPU cooler heatsink should work quite well. That little one that I tried is barely anything, but does work. I'm trying to reduce the form factor of the LED head to something less than bull-lantern size. The reflector is 70mm in diameter, so the ideal heatsink would fit into a 70mm or so tube.
I think a cut down CPU cooler heatsink should work quite well. That little one that I tried is barely anything, but does work. I'm trying to reduce the form factor of the LED head to something less than bull-lantern size. The reflector is 70mm in diameter, so the ideal heatsink would fit into a 70mm or so tube.
I chopped down a AMD processor heatsink so that it would fit in a 3" diameter tube (to match the reflector and standard high powered model rocket sized body tube sizes). The 70 mA fan does keep it cool enough. Faster fans work a lot better. One issue may be feeding air in and out of a compact light head. I may go with 18650 A123 cells for a real compact version. Would only run 20 minutes or so out full beam power. A big honkin' bull lantern with 12 or 16 Ah Headway cells is another possibility. Those would run 6-8 hours at full brightness (or 3 months on dim)
Just when you thought it was safe to go out in the dark... it looks like Bridgelux may have obsoleted that 5000 lumen C4500 array. It does not show up in their latest data sheet. What does show up though is the C8000... and 8800 lumen beastie. Plus a few other arrays.
These new LEDs don't have a voltage rating that is quite as well matched to LiFePO cells as the older ones. The C800 might be a little underpowered at 9S and over powered with a fully charged 10S pack. My LED driver does back off the PWM duty cycle at higher voltages, so it should be fine. Once the pack drops to 3.4V per cell, it is in spec. It only takes a couple of minutes for a fully charged pack to drop to its 3.3V nominal per-cell rating. Once nice thing about running a 10S pack is that you can use a stock DeWalt pack.
I built up a light head with the C4500 array, a cut down Athlon heatsink, and a 50mm 24V fan. Works very well. It will totally illuminate my large-ish 2 story house and yard.
These new LEDs don't have a voltage rating that is quite as well matched to LiFePO cells as the older ones. The C800 might be a little underpowered at 9S and over powered with a fully charged 10S pack. My LED driver does back off the PWM duty cycle at higher voltages, so it should be fine. Once the pack drops to 3.4V per cell, it is in spec. It only takes a couple of minutes for a fully charged pack to drop to its 3.3V nominal per-cell rating. Once nice thing about running a 10S pack is that you can use a stock DeWalt pack.
I built up a light head with the C4500 array, a cut down Athlon heatsink, and a 50mm 24V fan. Works very well. It will totally illuminate my large-ish 2 story house and yard.
Well, I just about have the house fully converted to LED bulbs. Instead of costing $12,000+ it looks like the total will be under $3000. I got some REALLY good deals on "used" PAR30 and PAR38 bulbs off of Ebay. They were very high quality all made-in-USA units. Were probably store/utility company returns. Retail was around $70 a bulb and my costs were around $10 a bulb (less than 3 times the cost of incandecents that only last a few months around here).
Also got some PAR20 bulbs from the same source for doing the outside bulbs on the house trim (they were too dim for use inside where I had to spring for a bunch of $20 bulbs). Heck, I even have LED bulbs in the garage door openers, closets, basement, and attics.
About half the total cost is replacing the 32 MR16 50 watt/900 lumen 12 volt halogen bulbs. These are in recessed "eyeball" fixtures that shine down onto artwork on the walls. The brightest MR16 LED bulbs in the US are less than 350 lumens. Philips sells a 400 lumen bulb in Europe... it has a fan in it that is rumored to be rather audible. The MR16 fixtures are the only source of light in a couple of rooms so need to be bright.
So I am building my own luminaries using a 1000 lumen Bridgelux array ($18 ea - I can push the LED to over 1500 lumens), Ledil reflector ($4), a Nuventix heat sink ($8), my own LED driver ($8 - a sweet, simple, serendipitous analog design), CCTV camera mount ($4), maybe a camera lens UV filter for LED protection ($2). The whole unit will be around 3 inches in diameter and a little over 2 inches long. They will hang down from the current eyeball cans on the CCTV mounts like track light fixtures.
Nuventix claims the heat sink has around 1.3 degree C per watt temp rise. I'll be pushing less than 15 watts into it, so should have less than 20C rise. Nuventix sells some really neat "synthetic jet" cooler modules that bolt onto the heat sink. They are basically "semi-no moving parts" coolers with 100,000+ hour lifetimes. They can boost the heat sink to handle over 30 watts, but their design guide says I don't need to use them for my load... we'll see... I have parts for 6 prototypes on order.
Also got some PAR20 bulbs from the same source for doing the outside bulbs on the house trim (they were too dim for use inside where I had to spring for a bunch of $20 bulbs). Heck, I even have LED bulbs in the garage door openers, closets, basement, and attics.
About half the total cost is replacing the 32 MR16 50 watt/900 lumen 12 volt halogen bulbs. These are in recessed "eyeball" fixtures that shine down onto artwork on the walls. The brightest MR16 LED bulbs in the US are less than 350 lumens. Philips sells a 400 lumen bulb in Europe... it has a fan in it that is rumored to be rather audible. The MR16 fixtures are the only source of light in a couple of rooms so need to be bright.
So I am building my own luminaries using a 1000 lumen Bridgelux array ($18 ea - I can push the LED to over 1500 lumens), Ledil reflector ($4), a Nuventix heat sink ($8), my own LED driver ($8 - a sweet, simple, serendipitous analog design), CCTV camera mount ($4), maybe a camera lens UV filter for LED protection ($2). The whole unit will be around 3 inches in diameter and a little over 2 inches long. They will hang down from the current eyeball cans on the CCTV mounts like track light fixtures.
Nuventix claims the heat sink has around 1.3 degree C per watt temp rise. I'll be pushing less than 15 watts into it, so should have less than 20C rise. Nuventix sells some really neat "synthetic jet" cooler modules that bolt onto the heat sink. They are basically "semi-no moving parts" coolers with 100,000+ hour lifetimes. They can boost the heat sink to handle over 30 watts, but their design guide says I don't need to use them for my load... we'll see... I have parts for 6 prototypes on order.
For those who asked for pics of the Big Bad Bridgelux Beam Blaster:
The 5000+ lumen array mounted on a P4 CPU heatsink:
The flashlight arrangement: LED array mounted on cut-down heatsink with 50mm fan, 28 degree reflector, LED controller board, 8S1P A123 pack.
Beam shot down 100+ foot driveway. Pitch dark otherwise. It's rainin' photons:
The 5000+ lumen array mounted on a P4 CPU heatsink:
The flashlight arrangement: LED array mounted on cut-down heatsink with 50mm fan, 28 degree reflector, LED controller board, 8S1P A123 pack.
Beam shot down 100+ foot driveway. Pitch dark otherwise. It's rainin' photons:
yopappamon
10 kW
Yay, pictures!
Alan B
100 GW
Nice clean photon flood.
Yeah, that Ledil reflector makes a perfectly clean beam. No hot spot, no fringes, no color cooties. That one is 28 degree beam width at half intensity. They have a wider one. Without the reflector it is 110 degrees.
The 8S1P A123 26650 pack drives it for an hour at full blast. 10 days or so at minimum.
I got in some Nuventix heatsinks ($7) for the luminaries that I am building for the house. Really nice. About 3 inches diam/2.5 long. I am using a 1000 lumen/13 watt array. I have laid out a driver board that mounts on the back end and am having them fabbed.
The thing runs a bit hotter than I expected (68C vs 55C) but is well within spec. I think their heatsink thermal resistance spec was with their synthetic jet cooler module attached. The LED can run at 150C junction temperature. Those 50 watt halogen bulbs run at 800 degrees.
I am using the glass from a 58mm UV camera lens filter for my front glass. Fully anti-reflection coated. Only 2 bucks, shipped. Total cost is around $45 each. I need 31 of them...
Front view with LED/reflector/front glass
Side view
The 8S1P A123 26650 pack drives it for an hour at full blast. 10 days or so at minimum.
I got in some Nuventix heatsinks ($7) for the luminaries that I am building for the house. Really nice. About 3 inches diam/2.5 long. I am using a 1000 lumen/13 watt array. I have laid out a driver board that mounts on the back end and am having them fabbed.
The thing runs a bit hotter than I expected (68C vs 55C) but is well within spec. I think their heatsink thermal resistance spec was with their synthetic jet cooler module attached. The LED can run at 150C junction temperature. Those 50 watt halogen bulbs run at 800 degrees.
I am using the glass from a 58mm UV camera lens filter for my front glass. Fully anti-reflection coated. Only 2 bucks, shipped. Total cost is around $45 each. I need 31 of them...
Front view with LED/reflector/front glass
Side view
I got to test my Bridgelux LEDs last night on an integrating sphere light meter. Their raw output is spot on to the specs (try that with a Chinese LED). Unfortunately, you lose about 25% of the light in the beam forming reflector and front glass once you mount them in a fixture.
Paul_G
10 kW
100's of lights tested, some are bike lights tested in sewers, country roads, snow to u name it....a lot of work there.
http://fonarevka.ru/indexen.html
Paul G
http://fonarevka.ru/indexen.html
Paul G
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