Finally the XHP70.2 emerges!

[The_Driver1 (The_Driver)]

[quote=Texas_Ace]

@djozz

Although while it may survive that high I can guess that running it above ~15A is going to be a matter of quickly diminishing returns to the point of silliness when you factor in the heat it will produce.

The 15A buck driver you developed is starting to make a lot more sense now.

[bibihang]

@Tom E

Wow! Nah, I don’t believe in limits or thin wires .

Ok, here’s some details. It’s a TA Convoy L6 triple channel using a SIR800DP, 20 AWG wires, 20 AWG spring bypass. It’s got the Simon SMO reflector.

On 2 LK 5000’s at 4.17V, I got 18.0 amps on the clamp meter.

Lumens: 8,940 start, <strong>8,090</strong> 30 secs. Throw at 5m: 186 kcd (862 meters)

There is no black hole, well under 1 foot to a white wall there is, but nothing further away than 1 foot. It’s got the usual new LED yellow around the hot spot. Could be the 3B tint, or just the nature of the LED’s with our typical reflector designs.

The thing gets hot, maybe the hottest I ever felt after 30 secs. I didn’t let it cool down much before getting the throw readings, and it was getting darn uncomfortable holding it for the 30-40 secs or so.

Is this thing usable? Well for a few moments, yes. I had two EVVA unprotected 4000K cells I tried. They were at 4.05V and I got about 11A on the clamp meter, and maybe about 6,800 lumens at start.

Surprisingly, ramping seemed to be working ok, but as has been pointed out, there’s not many steps in the ramping table at the high levels, so it jumps bright fairly quick at the end.

You flashlight mad scientist!

[Fatlight]

Meh, it came as expected . there was so many naysayers saying it wont happen but knowing Cree , getting Xhp70.2 was only a matter of time and cost.

Now i plan to pop one into a Boss with 4x26650 16v DD on a beefy 50mm thick chunky heatsink to get a whopping ~10k lumens single emitter compact thrower worthy of a flasholic envy. :+1:

This is what i call ‘Pushing on the limits of existing technology’. Doing anything less would be better off going the way of buying a production light.Why bother……

[mrheosuper]

sorry, i dont keep up with the topic
if i change all the XHP70 in my olight X7 to XHP70.2, how many lumens i will gain, and is it worth doing

[Enderman]

@mrheosuper

sorry, i dont keep up with the topic
if i change all the XHP70 in my olight X7 to XHP70.2, how many lumens i will gain, and is it worth doing

Nobody has done tests yet.
It will also depend if you’re using a CC or DD driver.
If it’s CC then you will get an efficiency increase and probably very little additional lumens, if it’s DD you will get an efficiency decrease and much higher output.

[Enderman]

@The_Driver

The 15A buck driver you developed is starting to make a lot more sense now.

Link to the driver?

[The_Driver1 (The_Driver)]

@Enderman

@The_Driver

The 15A buck driver you developed is starting to make a lot more sense now.

Link to the driver?

The Texas Buck driver series, Q8 / Skyray King 2S/4S buck driver RELEASED!

So after a bit of an on again, off again relationship with this driver I think it is finally ready for it’s first field test. This driver is a 46mm Q8/SRK sized driver capable of driving up to 15A @ 4S (16.8V) on paper. It can also be used with 4S input to 2S output and 2S input to 1S output. Ripple current should be less then 2% Thanks a ton Flintrock! He is the only reason this was completed at all, I did not remotely have the time or skills to pick through all the components to make this …

[Enderman]

[JasonWW]

Vinh at Sky Lumen got a batch of these 70.2’s in and has already made a few 20k+ lumen monsters.

[SteveMidwest]

@JasonWW

Vinh at Sky Lumen got a batch of these 70.2’s in and has already made a few 20k+ lumen monsters.

[mrheosuper]

Of course it’s CC driver
Currently it’s about 3000 lumen per xhp70, still not the maximum
I think if i change to ver 2, maybe i will reach 10k-11k lumen

[AEDe]

Could you help? I m looking for 16 mm DTP mcpcb for xhp70 for 12 V and with isolated thermal pad.

[finges]

@AEDe

Could you help? I m looking for 16 mm DTP mcpcb for xhp70 for 12 V and with isolated thermal pad.

IMO for 12V there is none. However there is one modified 16mm one for 6V only available here XHP70 6V 16mm DTP Copper MCPCB
But I think this process is not possible with the 12V pcb.

[Wieselflinkpro]

@AEDe

Could you help? I m looking for 16 mm DTP mcpcb for xhp70 for 12 V and with isolated thermal pad.

12V: http://kaidomain.com/p/S025183.16mm-Dia-x-1_5mm-T-12V-DTP-Copper-MCPCB-for-Cree-XHP70-2pcs
But what do you mean with isolated thermal pad? It is connected to the LED-Base directly.

6V is also aviable: http://kaidomain.com/p/S025182.16mm-Dia-x-1_5mm-T-6V-DTP-Copper-MCPCB-for-Cree-XHP70-2pcs

[AEDe]

I mean isolated from - and +.
In mcpcb above thermal pad connected with - (or + it doesn’t matter)
In 6v version thermal pad is isolated but not a in 12v.

[Wieselflinkpro]

@AEDe

I mean isolated from - and +.
In mcpcb above thermal pad connected with - (or + it doesn’t matter)
In 6v version thermal pad is isolated but not a in 12v.

I does not know any mcpcb where the terminal pad is connected to LED+ or LED-.
Only some LEDs like Osram Oslon black flat have a connection between terminal Pad and LED-.

With DTP (direct termial path) the terminal pad can be connected to the flashlight body, which mostly is connected to battery-.
A connection of battery+ to the flashlight-body is very rare. I have made such a connection in a Skyray King with Nichia 144 LEDs, which do not have a terminal pad.

[AEDe]

The diode contacts are not isolated from thermal pad, just look at image from kd. I want to use boost driver that require thermal pad to be isolated from driver out.

[Wieselflinkpro]

OK, now I know what your problem is.
… as it is written in the datasheet of XHP70: “Recommended PCB Solder Pad 12 V Configuration (thermal pad is connected to anode and cathode and is not electrically isolated)”

Than you need to do it yourselfs.

On the 6V Board, you can cut the traces in the middle of the + and - pads to connect the new pads among each other. That means, you will not need capton. You can use the “CREE” and “XHP70” scripting on the board to connect the new pads with a cable.

[Enderman]

@Ollie

Enderman,
I’m not picking on you, but I tried the 3s direct drive with the 12V XHP 50.2. It works, but not very well. I had an empty 3D Maglite, and got the idea to put in a 50. It worked, nice beam, but wasn’t very bright. Went in and measured current at the tailcap; .5A. Hmmm. So I stuck a handy 5200 Keepower on top (yeah, mixed batteries, but only for a second), and got 3.7A. Now that’s more like it! I also had a 4D with a showerhead LED setup, so I swapped my build into it. With 4 elderly 4200 Mah 26650s, it pulled 3.3A! Great light! At that point it seemed feasible that 2 26650s should be even more safe with a 6V 50, as it should sag even further. It did. I switched to 2 Keepower 5200s, and the current was 6.7A. It’s still under 2C, so it’s not a battery killer.

I’ve run out of copper heatsinks in that configuration, so my third 50-build will use an aluminum sink. It’s a bit longer, and I’ve run aluminum sinks in 2 quad XM-Ls I built some years ago; no sweat. I am going to switch from 16 gauge ground wire to 22, but that’s more for the convenience of greater flexibility.

As TA and others have mentioned, it’s about heat management. You fire up the light, and the sink and the head of the light are at ambient. Gradually the light heats up, but as it is doing that, the battery voltage is dropping, hence the current is reducing. At some point the heat will begin to nose over, assuming nothing melted. Now if you really wanted to blow stuff up, at that point you could put in fresh batteries. That might do it, but that is not a realistic usage of the light. If I wanted to build a S&R light, I would add some resistance, or a driver. In fact, the problem with building DD lights is usually making sure that no unintended resistances creep into your build. Yes, the light probably becomes less bright as the run goes on, but given the way the human eye responds to light, this will not be noticable for quite a while.

DD lights are fun and easy to build.
Ollie

Interesting.
Still waiting for someone to test the XHP70, 20A without burning up and still making good output sounds impressive based on the rough tests a few posts ago.
If it can do 20+ A with less than 8.4v then it will probably do more than 0.5A with 12.6v in the 12v configuration.
Only tests will tell for sure

[djozz]

I received a XHP70.2 from KD (P2 3B) yesterday and did a test with my usual method. I could not repeat the results of Tom and Kawi, the led maxed out at 12A (I measured 6600lm), above that the output slowly went down. I stopped the test at 15A. After cooling down I tried going directly to 15A and got 8000lm at start and 7000lm at 30 seconds. Considering that Tom got comparable numbers but out the front of a flashlight, so maybe 15% less compared to bare led lumens (which would be 9200lm and 8000lm), I’m on the low side of them.

I checked my reflow by unsoldering the led, and the led made good contact over the entire solder pads.

A very possible explanation for our differences could be my way of mounting. I think the (active, with a fan) cooling of my rig is good enough or at least as well as the flashlight builds of Tom and Kawiboy, but the (20mm) ledboard was not soldered on the heatsink, but screwed down tight with thin ArticSilver5 in between. With the close to 100W of heat to dissipate, this may be a limitation. When I have time I will solder the 20mm star onto a larger 3mm thick copper disc, and clamp that to my test-mount, so that the contact surface is way larger (more than 3 times). Then I will do the test again, and make a post about it.