Modded: Small Sun ZY-T13 3.2 Amps or Sunwayman T40CS Clone

Op hows this flashlight going? Any issues after you modded it?

awesome mod. does it throw as far as a stl v2/v6 now?

Can someone tell us how can we solder the three legs of trimpot

You’re using it as a variable resistor, so connect the center lead to either of the other leads and just use those two connections. I’m a little weary of using a trimpot for this application though. What kind of trimpot, what power rating/current, etc… Trimpots aren’t generally made to handle much current.

Has anyone simply swapped out the driver for proper output? The side switch is nice
but i’ll throw it overboard to save the LED

OK, great instructions!
I received the light today and IMO it is a very good light for the price paid.

I ordered some 0.68Ohm resistors, I hope they are “close enough”. 2 or 3W, they were one or the other…

One question though:
Which way should I solder it, blue or red?

I looked at the board from the back using a strong light and both resistors seem to be soldered in parallel, anyway I soldered the trimpot at each side of the R200 resistor.

EDIT, PLEASE READ:

I noticed that the resistor values from your board are 150 and 200 mine were 220 and 220, IMHO your light has more amps driving the stock led than mine had in stock form, check the current at the tailcap, I think the resistor you got will overdrive the led.

CheapThrills STOP!

I just noticed that the resistor values on your board are different from mine! Please measure the current at the tailcap from the stock board and report back before you mod anything!

I think you are going to overdrive the led with that resistor!

Looking closer at the board in your light it looks different from the board in my light, mine has 2 additional electronic components near the resistors and yours does not (one look like a diode to me, the other I have no clue!) I would recommend to NOT MOD IT until someone more knowledgeable in electronics takes a look at your board and chimes in.

Hi!

Sorry, pic is just for reference from another thread. AFAIK it is not even the same driver.

I have the light at me now but I have not yet even disassembled yet since I´m still waiting for resistors.
So, no worries yet :wink:

Anyway, the way “blue” would be the preferred?
(will post pics later from actual driver)

AAAAAAAAHHH! just as this thread is resurrected,my zy-t13 died,put both batteries into protection and does so to other batteries too.Don't have time to diagnose,but this sucks I really like this light.If anyone knows of a decent 8.4v low PWM driver@3 amps or so,I'm open to suggestions.I don't really care about the side switch at this point.

Had some time so I took some measurements.
Supplied the driver from a power supply, read supply current from power supply display.
Measured LED current with a current probe connected to an oscilloscope.
There’s some wiggle-room to my results since the LED star wasn’t mounted on anything,
I only always quickly powered on, took my readings and powered off.
But the LED will have heated up a bit.

The 0.22Ohm resistors on my driver board are in parallel, resulting in a combined resistance of 0.11Ohm (=110 mOhm)
The resistors are in the input-current path of the driver.
Input power is a fairly constant ~7.5W
Output current to the LED is a fairly constant 2.05A
(2.1A at 6V VBat to 2.01A at 8.4V VBat)
Calculated efficiency is ~80%

I made some calculations for resistor values but they turned out to be a bit off, maybe because of temp influence.
I had calculated that I’d need ~370mOhm in parallel (—> 85mOhm resulting resistance) to get to 2.5A

All I had available were 1 Ohm resistors, so I soldered 2 of them in parallel (—> 500mOhm added in parallel, resulting resistance 90mOhm)
And those actually gave me 2.5A at the LED.

Then I added another 1 Ohm resistor in parallel (—> 333 mOhm added in parallel, resulting resistance 83 mOhm)
With those values I got 2.73A at the LED.

I stopped there.
Based on the measurement results I calculated that if you want ~3A through the LED you’ll need to add ~227 mOhm in parallel to the existing 2x220 mOhm resistors. The overall resistance then would be ~75 mOhm.

The 2x 220 mOhm (=0.22 Ohm = R22 listed on the components) on my driver board are 0805 SMD components,
in case you want to buy the same size for easy piggy-back.

Quick summary:
table(table#posts).
||LED current|Total R|R that needs to be added in parallel|
||[A]|Ohm|Ohm|
|original|2.05|0.11|N/A|
|tested|2.5|0.09|0.5|
|tested|2.73|0.083|0.333|
|calc.|3|0.075|0.227|

-S

I added one 0.68Ohm resistor parallel to those R22 resistors and got about 1.17A of draw.
I´m now recharging for readings with a full set of batteries.

edit: Full batteries and 1.10A draw.
Ordered some R22 SMD resistors, thanks!!

I dont want to opet a new topic about this so Ill try to get an answer here.

Well, I have 2 SMall SUn ZY-T13, and with both I have same pronlem, they are shorting out.

I dont know exactly where and thats troubling me…

Anyone other had that experience.

Driver placement in this flashlight, with that alu-ring on top of it, is littele messed up.
Probably driver is shorting out somewhere butits hard to tell where.

One is with stock driver, and the other is with ST50 (not sandwich) driver. But forget about that modded one, I wanna concentrate on this one with stock driver.

I really dont know whats happenining and where this short occurs, because, because of mnessed up driver placement, there are many possibilities, and Im not so experience to huess what would be most probable source of shorting…

Did you remove the LED centering ring?

No…

its not shorting from the reflector.
Im pretty sure that driver is shorting somewhere, maybe that retaining ring too.

Im pretty sure that this setup has design flaw somewhere, but I didnt succed oto pinpooint it yet…
Because I think there is lots of weak points and possible shorting points here…

FOr example driver (+) spring and driver retaining ring
retaining ring and bottom of the driver.
Other side of the driver with insides of the “tube” or “pill”, dont know how to call it (on the side or to the emmiter side)
Mybe I forgot something - but its not reflector…

Heh, little update.

It seems it is not shortcircuit after all.
I thought it was shortcircuit just because of sparks sometimes occur on the en of the battery-tube - weather when Im screwing on the tailcap (you can even here small crackling noivces), or when I close the circuit by some metal or scissors.

I dont know why this occurs, but it is not short-circuit (as flashligtht wouldnt shine with short circuit, as my friend explained to me - i dont know much about electricity).

SO, its basically some sparks when there is weak connection on the tailcap - its not short circuit…
When tailcap is screwed all together everything works fine.

….Also, just to tell you guys, these are somewhat good flashlights (especially that big head and reflector, but with cheap driver and internals — so output heavily varies from unit to unit.
SOme units are brighter, some are less bright. Also hotspot is not always the same…

Ive modded one unit with P7 3,0A (1,5A measured at the tailcap, 1,0A with stock driver) driver from lightmalls and Im satisfied, but it doesnt have mode memory quick as I hoped….

Dude! I just threw 500m with this thing!! Holy smokes!

Only mod was 2x(0.47ohm) to get ~1.55A. And of course, a perfect dedome.

I got back at night, and I just came across a a bird's nest building in the middle of paddy field (they're huge, and white). And since I brought my T13, I just had to try. BAM! Clear as daylight. Metaphorically of course, but you get the point.

Google Earth told me it's 500m. Sadly no pics, didn't bring camera at the time. Will try again next time I go through there.

OK….
I think I got the wrong resistors or something:
Bought these for a couple of bucks : http://www.ebay.com/itm/261113307852?var=560163266936&ssPageName=STRK:MEWNX:IT&\_trksid=p3984.m1497.l2649
R22. Now, is it 22Ohm or 0.22Ohm?? The first one would explain, why I cannot get it working properly no matter how I solder it!

They only list a 22R, which is 22Ω

What you’d need is one that says R22 or maybe also 0R22

-S