BLF GT94 vs HID. LED has surpassed HID in my opinion.

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

Also you can see that the hottest part of the head is only 165F which is well within its temperature limits.
Haha I like a good debate.

This temperature actually means very little, The "head temperature limits" are the melting point of aluminum , Its the temperature of the LED's themselves, the Junction temperature that matters a VERY LOT. You need a very large "Delta T" between the heat sink fins and the LED's themselves (As well as a very good mechanical (physical) connection for thermal transfer) in order to have very efficient thermal transfer to pull the heat out of the LED's . Once the heat sink warms up you no longer have that "Delts T". With the heat sink fins at 165 degrees you can be assure the LED's are likely above or at least close to 100C (212 F). That's well above whats good for LED's or any circuitry for that matter for long dependable life. This is why on computer CPU's the heat sink mechanism has been directly attached to the top of the CPU and then a fan as well.
There is no way to get the heatsink directly onto the back of the LED's, they are mounted on a PCB (plastic) etc.
How many watts are being drawn from the battery in this situation ? All those watts that end up as heat must go somewhere, much of it is being trapped inside.

As "someone" politically famous (unnamed here) a few months ago said, "it was just a debate (while laughing:fail" when confronted in a video recorded interview for extreme inconsistencies of opinion and position (implying that misleading comments are normal and to be expected in a debate). ie Political "Flip - Flops" positional lies are normal.
Fortunately this debate isn't Political in the traditional sense, but is seems to have gone well beyond the scientific facts of high powered LED flashlight thermal management design. You simply can't ignore the Physics of thermal energy (heat) transfer. Ambient airflow (natural convection) and radiated IR just cant cut it, submerged in water would likely do the job or possibly cool or cold strong winds.

 

[Magio]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

The MCPCB is not plastic. It's 88mm by 3mm copper and weighs about a 1/3 of a pound. The LEDs maximum junction temp is 150c or 302f. I doubt those LED are getting that hot.

 

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

If it were "copper" the entire PCB would be a giant short. It is backed and bonded to a copper "plate" of your indicated 3mm, the plastic PCB is a thermal and electrical insulator, with the power pads to mount (solder) the LED's not connected thermally directly to the copper plate.
You better get it straight if you are gonna argue with me. I have been in LED applications development (Aviation) for 8+ years.
You are crazy if you think 150C is okay for any Diode. Maximum PCB temperature for any electronics application is about 120C, that's not considering the maximums for individual devices mounted thereon or their longevity.
Whats the Tg (glass transition temp.) of the PCB ? should always operate at least 25C below the Tg rating.

 

[Magio]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

If it were "copper" the entire PCB would be a giant short. It is backed and bonded to a copper "plate" of your indicated 3mm, the plastic PCB is a thermal and electrical insulator, with the pads to mount (solder) the LED's nt connected thermally to the copper plate.
You better get it straight if you are gonna argue with me. I have been in LED applications development (Aviation) for 8+ years.
You are crazy if you think 150C is okay for any Diode. Maximum PCB temperature for any electronics application is about 120C, that's not considering the maximums for individual devices mounted thereon or their longevity.
Whats the Tg (glass transition temp.) of the PCB ? should always operate at leas 25C below the Tg rating.

Yes this is appropriately called a copper dtp mcpcb. Trying to find something wrong with the light by calling it plastic is just silly. I think there is enough information here for others to make their own judgements.

 

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

I think there is enough information here for others to make their own judgements.
Trying to find something wrong with the light by calling it plastic is just silly.

On that statement I believe we can all agree that intelligent conclusions can be made, from these complete 25 informational posts.

Every PCB made in the world is made of some type of insulating fiber reinforced plastic, that's not a criticism, just a fact, HID is the same.

 

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

On that statement I believe we can all agree that intelligent conclusions can be made, from these complete 25 informational posts.
Every PCB made in the world is made of some type of insulating fiber reinforced plastic, that's not a criticism, just a fact, HID is the same.

I guess the debate has been "laid to rest" again for a time, until another "wack a mole" event.
Eventually it will happen but these current arguments are premature.

Who knows, perhaps my company will be the one to accomplish a comparable performing LED to a high quality "military grade" HID.
A unit with a few hours of "turbo" continuous run time without any performance or life degradation and ~10,000 Lumens, and not burn your hands or damage the LED's

 

[Magio]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

The GT94 is already quite capable of running continously at a level that exceeds HID without burning your hands or damaging the LEDs. And this is not the only light thats capable of it. Vihn's moddified Mateminco MT90 is capable of continuous 5,500 lumens at 3.3million candle power. And the heat management in that light is even better than it is in this light. This guy https://www.candlepowerforums.com/v...-COMING-SOON&p=5410198&viewfull=1#post5410198 measured only 127F after 15min and 112F with the fan. And yes you are right that there will continue to be improvements. The 2 lights that I have mentioned are big and weigh about 8lbs. I would like to see the size and weight come down to something a bit smaller and more manageable.

 

[Rasher]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

The GT94 is already quite capable of running continously at a level that exceeds HID without burning your hands or damaging the LEDs. And this is not the only light thats capable of it....

As an owner of a '94, and most of the other "super" LED, they're not in the same league as the top-o-the heap HID, certainly not for throw, runtime, or temperature limits. One need only take out a Xemax, Lemax, maxa beam, etc. to clearly see it's comparing Yugo to Ferrari. They are not toys, and are priced accordingly.

 

[idleprocess]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

Every PCB made in the world is made of some type of insulating fiber reinforced plastic, that's not a criticism, just a fact, HID is the same.

There are a wide variety of MCPCBs out there. Many are just a thin veneer of FR4-like material over an aluminum layer that use via-like constructs under the thermal slug of the LED (or other high-power component) to conduct heat to the metal core far more efficiently than vias through a conventional PCB to an outboard heatsink. Some are more exotic with towers or pillars that project through the FR4-like material for direct contact with the thermal slug and look to be made from copper rather than aluminum. A quick search turned up COFAN USA, who claims significant jumps in thermal conductivity with a pillar design vs conventional MCPCB design. A product from Cutter designed for a handful of specific Cree LED's claims similar thermal conductivity.

Who knows, perhaps my company will be the one to accomplish a comparable performing LED to a high quality "military grade" HID.
A unit with a few hours of "turbo" continuous run time without any performance or life degradation and ~10,000 Lumens, and not burn your hands or damage the LED's

With LEDs getting steadily cheaper and something akin to the replaceable-component concepts that Zhaga attempted to promulgate, perhaps the light source could be replaceable as needed - ala HID - to get around the problems of degradation when operating at extreme temperatures for long periods :shrug:.

 

[desert.snake]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

I thought HID died as soon as the LEDs appeared, too much power eat and they are afraid of falls.

Magio Why shine such powerful lanterns at your feet? They are designed for use with binoculars, to search for something over long distances. For example, look for prisoners or animals to shoot at night:



In my opinion the GT94 is ineffective, Like most other luminaires with reflectors, because a lot of light goes into side illumination. TIR and fresnel lenses will provide excellent beam without additional loss. Better to have 10-15 emitters that will give the same beam as 3-4, but will be colder.

I always remember an old funny video where they made a spotlight from a steel bowl and a fresnel lens
https://www.youtube.com/watch?v=AxTGS5i2AHY

Thanks for the thermal pictures of the flashlight, it's helpful. The lack of thermal protection for the batteries is sad. I mean an additional temperature sensor that would be located between the head of the flashlight and the batteries in order to monitor the extreme temperature and reduce the power when the batteries heat up. Once my battery wrapper from a well-known manufacturer of flashlights melted. they have not indicated anywhere that there is no thermal protection. By the way, in the video, there is a temperature sensor on the diode board, there is also a temperature sensor on Luminus CBT diodes from the luminus to monitor and protect the diodes, there is also a place for installing a thermal sensor on the diode boards from the MTN. Does the BLF GT have a similar sensor near the diodes?

 

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

The GT94 is already quite capable of running continously at a level that exceeds HID without burning your hands or damaging the LEDs. And this is not the only light thats capable of it. Vihn's moddified Mateminco MT90 is capable of continuous 5,500 lumens at 3.3million candle power. And the heat management in that light is even better than it is in this light. This guy https://www.candlepowerforums.com/v...-COMING-SOON&p=5410198&viewfull=1#post5410198 measured only 127F after 15min and 112F with the fan. And yes you are right that there will continue to be improvements. The 2 lights that I have mentioned are big and weigh about 8lbs. I would like to see the size and weight come down to something a bit smaller and more manageable.

Those temps tell you nothing of the heatsink to Junction transfer efficiency nor the Junction temperature or long term durability, Often of little concern to Chinese manufacturers.

8 lbs is a ridiculous amount of weight. 4 to 5 lbs, should really be considered a maximum including the battery.

 

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

I thought HID died as soon as the LEDs appeared, too much power eat and they are afraid of falls.

High quality HID's are not "afraid of falls", if the G's of impact are very high (hard surface like concrete), the plasma of the arc actually having mass can sometimes pull far enough away from the 2 electrodes at the moment of impact and the arc of light will extinguish.
If this happens its just a matter of restarting the light with no waiting needed, its called a hot restrike. Only cheap units or poorly designed ballasts have an issue with hot restrike.
As for power a 35 watt HID needs about 39 watts total power. A 50 watt HID needs about 55 watts, a 70 or 75 watt HID needs about 77 and 83 watts respectively.

 

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

With LEDs getting steadily cheaper and something akin to the replaceable-component concepts that Zhaga attempted to promulgate, perhaps the light source could be replaceable as needed - ala HID - to get around the problems of degradation when operating at extreme temperatures for long periods :shrug:.

With "Murphy's Law" being considered, reliability will be an issue with that approach and failure will occur at the most inopportune time.

 

[desert.snake]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

High quality HID's are not "afraid of falls", if the G's of impact are very high (hard surface like concrete), the plasma of the arc actually having mass can sometimes pull far enough away from the 2 electrodes at the moment of impact and the arc of light will extinguish.
If this happens its just a matter of restarting the light with no waiting needed, its called a hot restrike. Only cheap units or poorly designed ballasts have an issue with hot restrike.
As for power a 35 watt HID needs about 39 watts total power. A 50 watt HID needs about 55 watts, a 70 or 75 watt HID needs about 77 and 83 watts respectively.

This is cool, of course, but HID expects death or half-life awaits, like silver fruit knives with the advent of stainless steel. Price question for the ordinary flashlight lover. Sure HID will exist if only for some very special purpose (if heat removal is impossible for some reason) or someone who has a lot of money, some government structure.

 

[Chicken Drumstick]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

If it were "copper" the entire PCB would be a giant short. It is backed and bonded to a copper "plate" of your indicated 3mm, the plastic PCB is a thermal and electrical insulator, with the power pads to mount (solder) the LED's not connected thermally directly to the copper plate.
You better get it straight if you are gonna argue with me. I have been in LED applications development (Aviation) for 8+ years.
You are crazy if you think 150C is okay for any Diode. Maximum PCB temperature for any electronics application is about 120C, that's not considering the maximums for individual devices mounted thereon or their longevity.
Whats the Tg (glass transition temp.) of the PCB ? should always operate at least 25C below the Tg rating.

A shame you are ruining a good thread with constant scorn and negative views. Maybe you'd be better served going off and building a light to better this and proving how it is done if it bothers you so much.

 

[idleprocess]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

With "Murphy's Law" being considered, reliability will be an issue with that approach and failure will occur at the most inopportune time.

Don't know about your - nor comparably-priced - gear, but in the automotive world HID bulbs and ballasts have a tendency to do just that on timescales somewhat in excess of the factory warranty. I imagine that replacing items on a schedule all but eliminates unpleasant surprises. Of course, one has to perform surgery then diagnostics to repair most tightly-integrated automotive LED headlamps - but to the automakers who make good margins on parts this is likely a feature not a bug.

I got a decade out of a first-generation i5 desktop (i5-750) built from parts to a cost limit and only replaced it because it was beginning to show subtle signs of possible failure after the heatsink separated from the CPU a second time (hooray for thermal throttling). If a socketed 95W TDP CPU that doesn't want to much exceed 72°C can be made to last a decade in a consumer application with middling airflow spending its first ~5 years running 24/7, I suspect that in markets with more margins than residential/consumer gear a fixture or searchlight's high-power LED can be made field-interchangeable ala something akin to a socket that interfaces power and thermal management.

 

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

A shame you are ruining a good thread with constant scorn and negative views. Maybe you'd be better served going off and building a light to better this and proving how it is done if it bothers you so much.

My comments give out plenty of hints.

If you can't handle reality then maybe you should stay out of any debates.

Any technology or product that can't stand up on its own merits deserves confrontation.

 

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

Don't know about your - nor comparably-priced - gear, but in the automotive world HID bulbs and ballasts have a tendency to do just that on timescales somewhat in excess of the factory warranty. I imagine that replacing items on a schedule all but eliminates unpleasant surprises.

Our ballasts (any well made HID ballast) usually last many thousands of hours, you won't likely ever get there with a handheld.
As for the HID bulbs they usually last about 2000-3000 hours before total failure and almost without exception give plenty of warning (many hours).
They usually start to gradually turning pink or purple (the light beam) a few hours before absolute failure). The bulbs should really be changed out in 700 to 1000 hours for better output anyway.
The ultimate failure is due to the arc gap (gap between electrodes) getting too large due to erosion over time. The ballast has programmed voltage limits during steady state (warmed up).
Once a maximum voltage (typically around 100 VAC or so) is reached, the ballast will shut down automatically. This usually happens after maybe 10 to 30 seconds of run time.
Normal operating voltage is 85 VAC for a new bulb. In order to maintain a constant wattage to the bulb over its useful life, the ballast will reduce the amps as the volts AC needed rise.

 

[richbuff]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

This thread has caused my popcorn consumption to sharply increase. Reading this thread is both so exciting and so informative, but I had to drastically cut back on my usual diet of grains and beans (plain oatmeal and plain tofu), so as to not gain weight from the recent massive popcorn intake that has resulted from keeping up with this thread.

More throw or more power. More heat or less heat. More weight versus less weight. More runtime or less runtime. More durability or less durability. No final determination for me, except lots more popcorn calories.

 

[XeRay]

Re: BLF GT94 vs HID. LED has finallly surpassed HID in my opinion.

Will the new Supreme Court overturn HID v. LED?

Only if the LED favoring Dems. are able to "Pack the Court". This is after all a very "Hot Potato" political issue, its a form of systemic photonic racism.
HID is trying to hold LED down in a subservient role.