Hello and welcome
Took a moment to crunch some numbers, and assuming you guys are measuring tailcap current with fresh charged cells... 4.2V for 18650/26650 and 1.4V for the NiMH-C heres what I came up with:
benkie: 2x18650 => 54.6W
DRD: 4xC NiMH => 35.28W
Pok: 2x18650 => 30.24W, 3x18650 => 27.72W
oldienea: 2x26650 => 33.8W, 3x26650 => 27.9W
form: 2x18650 => 35.28W, 3x18650 => 32.76W
It looks like it draws more power at lower voltages. I have one on order, IMHO its a steal at $54 shipped. Looks like I may be using it in 3-cell configuration more than I thought.
This may sounds strange, but probably this is the reason. If you measure low amperage on single cell (direct drive) lights constantly, the dmm (or the leads) has a nice big resistance. Therefore, if you measure with this dmm on a real regulated light, the amperage will increase, because the driver will compensate the voltage loss, which appears on the dmm.
I missed this comment. I have found insufficient meter leads can cause all kinds of measurement inconsistencies. The OEM probes on my meter were driving me crazy, pulling my hair out trying to figure out whats wrong with my solder-work, wire routing or defective PCB components, when in reality it was inadequate meter probes. I bought some ~$17 probes, rated for 1000V / 15A... still affordable yet $$ WELL spent!!.. no more mystery head aches.
I tested it with good fully charged cells, i never do tail caps with any thing else. 6.5 amps is still under the 7.5 amp digital regulation. I have not been able to find my fluke since i moved house in last December, so i have brought another DMM it should be here next week.
The tr-1200 is digitally regulated at 2 amps on 2 x 18650,s and the tr-3t6 is digitally regulated at 3 amps on 2 x 18650,s.
So then one could think this about the tr-j12, since the manufacture has claimed it is regulated at 7.5 amps it would be on two cell's as the light does not work well on one cell it run is dim mode and if it was like the other tr lights i have the manufacture claimed regulation would be on 2 x 18650's.
Why would the tr-j12's regulation be one one cell as it has a dimming circuit for low voltage and it is a two cell minimum light.
I mention the regulation because this is what sets the TR lights apart from the skyray lights and so on, with the TR lights as the voltage drops the amps increase but it will not go above the digital regulation. The skyrays did not have this feature and the longer you used the light the higher the amps climbed till the lights driver failed.
Here's a graph that I made when I first got mine. This is with the head hooked up to my bench power supply (which tops out at 5A - resulting in the gaps)
It is slightly brighter on two cells than on three.
On 3 trustfire protected 26650's charged to 4.2 volt im getting 2.18 amps
Thats 27.5 watts, same as everyone else..... ? ? Strange how your 2-cell draw is so high.
Hi there,
Here are my results.
Equipment:
$15 eBay DMM -.-
intl-outdoor Panasonic NCR18650A 3100mAh (precharged two days ago; showing ~ 4.14v on DMM)
Brand new Duracell Alkaline C batteries (showing ~ 1.55v on DMM)
Duracell Rechargeable AA batteries (shows 1.2v/2000mAh on the wrapping; showing ~ 1.4v on DMM)*note: AA test done months ago*
Tailcap Readings (on High mode of course!):
2 x 18650 = 4.5A - 5.5A
3 x 18650 = 2.33A
4 x C = 2.50A - 2.75A
4 x AA = 1.8A
My readings shows that drd is correct, in that 4xC batteries is brighter then 3x18650 batteries.
Here are my amateurish pictures using iPhone below. lol
2 x 18650
3 x 18650
4 x C
4 x AA
Its a result of two things: a driver that is drawing more current as the voltage drops and a high resistance circuit.
With the 3 cell setup, a drop in voltage (due to the high resistance leads) makes very little difference in the current the driver needs. With 2 cells, the voltage is much more affected by the resistance and the problem is only compounded by the driver wanting more and more amps as the voltage drops.
If you are seeing readings over 5A, then the driver is only getting between ~4.2 and 6 volts.
On 2 trustfire protected 26650's charged to 4.2 volt each, I'm getting 6.83 amps. I does seem easy brighter on 2 cells over 3. I say all yours are just under driven since mine is still with in the manufactures claimed 7.5 max.
The light runs in dim mode only once voltage hits around 6 volt or below and is not that bright at all, but mine still is running in full brightness and you can change modes drawing 6 + amps.
Once the cells run down it will top out at 7.5 amps and will continue to run till it hits low voltage then drops out and dim,s the same as the manufacture claims.
6 volts or under the current draw drops drastically due to the dimming circuit and so does the brightness, the TR-3T6 and TR-1200 work in the same way once they are in dim mode below 6 volt. this is also about when the protected batteries cut out approx 5 to 6 volt depending on the battery.
The skyrays did not do this hence all the fried drivers with there early triples. Useless info 3.7 volt loaded the driver in mine will draw under 1.6 amps and at 2.7 volt it will draw under 0.58 amps.
So, is this light regulated on 4x ni-mh/alkaline C-cells? That would add an extra useful battery choice if it is.
informative thread thanks!!
I wonder why shopbot and benkie are pulling 42-55W at 8.4V, while it seems EVERYONE else is only at 30-35W? Sample to sample variation perhaps? I would think 8.4V is still too high for low voltage protection to be kicking in??
Hi Kramer,
Its pretty weird man. When I test the 2x18650 configuration, the reading fluctuates ALOT. There was like a range of up to 2A. I cannot pinpoint a good average whereas for all other configurations, I can get a nice somewhat consistent reading. Don't really know. Mind you my DMM was a $15 eBay one, so take it for what its worth.
I forget the current measurements, but I calculated the power at about 28 watts for any battery configuration (2 or 3 18650 and 2 26650). I only have 4 26650s, 2 of which are IMR, and two LiFePo4, so I don't want to mix chemistries/voltages to try 3 26650s.
About 4 days after I received the tr-j12, the spring behind the battery contact in the head either broke or dislodged, and now I have to use magnets as spacers for either 18650 or 26650.
Anyone know how to remove the pill from the head with breaking anything? It seems that the head is press-fit into place.
Most likely melted the spring. Mine did that, in the 26650 thread...
https://budgetlightforum.com/t/-/8886
If yours is like mine, there really is no "pill". The driver "engine compartment" comes apart, unscrews and separates the LED+reflector half from the DC-DC driver half. A pair of long wires deliver power from one section to the next. See my pics in the linked thread. The DC-DC board is pressed into the aluminum and a brass collar is threaded over it to lock it into place.
I gently stretched the spring back out and used copper braid to releve the spring of some of the current flow.
Welcome to the club, CME!
Mine doesnt have a spring at the head. It does have a spring with a cover on top. I get 3.85 V with two 26650's
Definitely viffer750 is right.
The input voltage is not higher than what 5 LEDs need and If the driver is regulated it has to boost the amps to maintain the brightness of all those 5 LEDs the multimeter+ leads will act as a voltage drop, showing high current draws, as it's already boosting the voltage. It doesn't matter matter how good the DMM (reg.Fluke) all have some burden voltage that will affect the reading in series with the flashlight on boosting circuits.
Thank-you. Glad to be here.