Junk Driver?

Okay so the title is pretty self-explanatory. I bought a driver doe my XHP70 project back in December and just got around to fooling with it last week. It's a buck driver, I think. The literature on it is vague Chinglish and doesn't give much detail. It's designed for 2S or 3S 8.4 to 12.6 volt input and 6 volt output. Rated current is 5 amps, but I had a feeling it was optimistic. Anyway, I hooked it up to a 12 volt 5 amp power brick and fired it up. The most current I saw was 3.1 amps. The modes work fine. I didn't get a voltage reading, but obviously it's 6 volts. So I think I got a dud driver. I haven't tried it on batteries yet. Would that make a difference? It gets pretty hot fast when at 100%. The seller won't respond to me. I paid like $8 after shipping/tax. Yes, I wanted to cheap out ;)

Any help is appreciated.

@Sirstinky, is it on the output side or the input side?

3,2A at 12V is almost 40W.

The current draw will go up as the voltage goes down during discharge.

That 12V is the input side. 3.1A at 6V is only 18W and the emitter isn’t even breaking a sweat. I was hoping for at least 30W. The current measurement is on the output side driver.

Should I try it on batteries? Would that help?

Thanks for replying.

Ooof. That wouldn’t change anything, but you should still try and see what happens with a battery pack.

3.1A is way too low.

Ummm, on the output side, you’ve got the LED and meter? Or just the meter?

The meter is measuring current between the driver and emitter on the driver’s negative output (that’s why the reading is negative).

Its your multimeter reading wrong to much resistance in your stock multimeter leads. Try testing with thick short wires instead.
Is the driver from Fasttech? I have a similiar driver modded doing almost 10amps.

Since that is a regulated buck driver it can be easier to measure the voltage drop at the current sense resistor than setting a multimeter with leads between emitter and driver, something which adds a lot of resistance because of leads, contacts and overall meter burden. If the sum of the previous figures is for example 0.5Ω the drop at 5A is 2.5V!

The driver doesn’t have a name brand. The listing on Aliexpress called it a “Manta Ray.”

I don’t have a lot of experience with these driver types,so it sounds like I’m not measuring the current right? I didn’t think the resistance was an issue, and my setup for testing the driver probably adds resistance too. I’ll try again a different way.

Thanks

Ah you used a multimeter.

You should switch to using a small wire with a known resistance(10mOhm) to actually measure its current.

That is a current shunt.

Great thanks for the tip. Like I had said, I am not super familiar with these drivers. How do I do that? Where is that resistor on the driver?

you may try one of my Buck drivers they can go up to 8A

2S—6V
3S—6V a bit reduced current due to more heat
and 4S—12V possiblöe

Your drivers are amazing. I considered mtn’s and yours, but didn’t want to spend that much initially since I wasn’t sure it would even work with my project. I will eventually upgrade the Chinese one once I get everything to work in my mod. My build is complicated since my host is plastic and I’m pretty much scratch building everything to fit around a cut-down Intel PC heatsink, led specific heatsink, 2, 26650s, Omten switch and all the internal connections.

you got also to consider that a Buck driver needs cooling, I can calculate on mine the losses
8A produces a lot heat like 4-5A is no problem with at least some heat path away like potting

while the Chineese tuned will likely get very hot

You are right about the heat. I expected that it would need cooling. While running it on high, the inductor gets too hot to hold my finger on it after like 7 seconds!

Lol i bought the mantra ray boost driver the 6v 5 amp driver its legit i also bought the 14 7135 the 5amp 22mm driver from them to try. The boost driver ive been using regulary its good but mode select is average.
I am sure the person who makes them is the cn/ cnc guy i think one of his shops was called that. He used to be a regular on here then went MIA. Who ever it is they have skills because the boards are designed from scratch by them.

Ill try and the person i am talking about. I don’t think hes logged in ages.

Perhaps you’re thinking of the user Ric-CN who was mentioned in this thread .

if the inductor gets too hot to touch within 7 seconds something is wrong on this driver

[qute=everydaysurvivalgear]Lol i bought the mantra ray boost driver the 6v 5 amp driver its legit i also bought the 14 7135 the 5amp 22mm driver from them to try. The boost driver ive been using regulary its good but mode select is average. I am sure the person who makes them is the cn/ cnc guy i think one of his shops was called that. He used to be a regular on here then went MIA. Who ever it is they have skills because the boards are designed from scratch by them. Ill try and the person i am talking about. I don't think hes logged in ages. [/quote]

Interesting. I got it off Aliexpress a while ago. I stick in some screen shots of who I got it from. It was one amongst many, but I chose it because it had the non-toridal inductor. Is it the same one? Maybe this seller is selling knock-offs of their design? Outside the expensive drivers there aren't many like this one that have the specified output and the flat top inductor...

I wouldn’t drive while junk , it’s against the law & very dangerous. :beer: