Sense resistor mod to KD Super Output P7 Driver

Flashlight Modding and DIY Parts
1

Question for the forum Gurus and Experts!

I have this Kaidomain driver that I use with 2 x 18650’s (8.4v) and gives around 3A to the led

I am wondering if it would be safe to solder one additional R120 resistor on top of the existing R200’s that the board currently has (3 o’clock position in the pic) and if I will get an increase in current to the led by doing this, can anyone estimate what the new current to the led would be by adding one R120 resistor?

Thanks in advance for your help!

AlexGT

2

Well, I just went ahead and did it and current did increase a bit, now using 2 18650’s is pulling 2.3a from a stock 1.8a, now my custom 2 1/4C Mag With Throwmaster reflector rivals my modded TN-31.

3

Nice work If you edit your post to include the name of the driver, then searches for this mod will find yours. I.e. Sense resistor mod to KD Super Output P7 Driver.

4

Agreed, will change it for future reference

5

Nice mod Alex. I have this driver. Were your measurements from the tailcap or at the emitter? Also, have you ever experienced the thermal cut-off feature this driver was noted for? What about low voltage warning?

6

I’ve used this driver for a few different mods, 2 bike lights and one handheld. 7x nimh for the bike lights and 6x nimh for the handheld. Both features functioned as described in Kd’s specs. A different blink for each and shift to low mode. I think lowV is two blinks and over temp is 3 blinks.

7

Current Measurements at tailcap

8

I can see me trying this, I have a couple of these drivers and like them a lot, boosting the current output is very pleasing to me.

9

Ok, I see this being used in an upcoming build, it seems 4.5a drivers are few and far between.

Just need to track down some R120 smd resistors now because a pot won’t work here :expressionless:

10

Fasttech carries smd resistors:

http://www.fasttech.com/category/1002/resistors/?smd%20resistors

http://www.fasttech.com/category/1002/resistors

http://www.fasttech.com/products/1002/10003143/1234403-0805-012r-smd-precision-resistors-100-piece

11

Cheers flow, just what I needed buddy 8)

12

Does anyone know if fitting another R120 resistor will increase the output current further?

13

I forget what resistors I added to mine, but it pulls ~3 amps at the tail

14

Adding another R120 will lower the total sense resistance, and very likely increase the output current, but the driver may or may not be able to handle it.

Edit: Has KD missed a decimal place? This thing cannot possibly cost $43.99.

15

That is for 5 pcs

16

Thanks. Didn’t notice that… :8)

17

Lightmalls has a better price.

18

Wow thanks for showing that, of all the high output drivers I have used that one has been the least troublesome.

Now I can get it cheap……

19

Thanks bdiddle, at least I know 3A at the tail is possible.

20

Anybody try this driver with an mt-g2 off 2 cells?