How to set the Flex Drive's Current.

[Mohrenberg]

This video is a bit lengthy. i encountered a common problem....and a solution. I was going to leave it unedited but it was 13 minutes long and youtube's limit is 10. So the edited parts you see are just me fumbling with something or taking forever to do something....no steps are cut out.

Setting a flex drive v5 using a rkcstr test load.

 

[daguin]

Dude! Get a set of "extra hands" and a switchable PSU. You are working much too hard.

I also use the "wire jumper" method to set the current range. It is much faster and easier than bridging the resistors with just solder.

Nice instructions though

Peace,
dave

 

[ColdStl]

I haven't watched the whole video yet, but I subscribed to your videos on youtube.
Thanks for doing this. Rckstr used to have a couple of cool videos as well, but I can't find them since the switch over to the new format.

Edit: just found them on youtube too.

 

[Mohrenberg]

I use to have a set of extra hands with the clips and magnifying glass, not sure where it went.

The problem with hitting a sensitive spot on the pot where you desired current is located....i have ran into that problem before but it wasn't untill i was making this video that i realized i could change the current range and thus change the spot on the pot where the desired current was located, thus moving it out of the sensitive area.

 

[pyrotech]

I use to have a set of extra hands with the clips and magnifying glass, not sure where it went.

Helping hands on sale now at Harbor Freight. $2.99

 

[Elektrotechniker]

What power supply did you use to test the flexdrive with the test load? It may be a silly question but I want to know. Also, is it safe to use my DIY testload?

 

[MrLWJPDX]

I finaly got around to building a dummy load for testing.
Hooked everything up using 6 diodes in this instance for a BluRay.
Checked everything about 4 times, put power to it.
I got a voltage reading on the output of 4.7 volts, but a mA reading of 12.00
It is a Flex Drive V4 that was set for 215 mA I wanted to reset it for the bluray.
Am I screwing something up or do I have a toast drive?
Thanks for an help.
Larry

 

[Elektrotechniker]

I finaly got around to building a dummy load for testing.
Hooked everything up using 6 diodes in this instance for a BluRay.
Checked everything about 4 times, put power to it.
I got a voltage reading on the output of 4.7 volts, but a mA reading of 12.00
It is a Flex Drive V4 that was set for 215 mA I wanted to reset it for the bluray.
Am I screwing something up or do I have a toast drive?
Thanks for an help.
Larry

At 215 mA there should be a bridge between the 2 resistors at the right. you would be in the current range of 100-312mA most likely. What current do you want your driver to output now?

 

[MrLWJPDX]

At 215 mA there should be a bridge between the 2 resistors at the right. you would be in the current range of 100-312mA most likely. What current do you want your driver to output now?

Info from Scopeguy was I should set it at about 140-150 mA. For a tested GGW diode.
And yes there is a bridge between two right hand resistors.
What I do not understand is the reading with the dummy load astride the resistor of 12.00 mA Or am I moron and reading it wrong and it really means 120. Mondays make many of us morons so that could be it.
Thanks for the reply.

 

[Elektrotechniker]

Info from Scopeguy was I should set it at about 140-150 mA. For a tested GGW diode.
And yes there is a bridge between two right hand resistors.
What I do not understand is the reading with the dummy load astride the resistor of 12.00 mA Or am I moron and reading it wrong and it really means 120. Mondays make many of us morons so that could be it.
Thanks for the reply.

Haha Make sure you use the correct reading settings on your DMM.. I have no further info to give you, sorry.

 

[MrLWJPDX]

Thanks Silvershot.
It is an autorange DMM so that is why i am wondering why I get a 12mA reading.

 

[pyrotech]

Micro Flex Drive problem, too

MrLWJPDX :
Did you ever resolve your problem? I've got the same thing, except I'm bridging all 3 resistors. I get 25mA no matter where the pot is set. I've closely inspected the whole board with a 10x loupe for stray solder bridges and bad joints, it looks good to me. Any Dr Lava experts out there? If there is something I can try, I'd love to save the $23 to replace this brand new driver.

 

[MrLWJPDX]

pyrotech,
Nope sent an Email to the Dr. Himself back on 11/23.
So far no answer, I am assuming other things are keeping him hopping during the holidays.
Hope get an answer eventually, I have all this cool stuff and no way to play with it yet.:cryyy: Don't want to buy another driver till find out whats going on with this one.
Thanks for checkin in, and Happy New Year to All.
Hope it is better than this one.

 

[Bluefan]

Can the driver supply the voltage needed by the blu-ray diodes? If the driver is powered with 5V, the small voltage drop inside the driver will make it fall below the voltage needed by the diode, so it can't reach the set current. Try supplying the driver with a little higher voltage, say about 1V extra.

 

[pyrotech]

Can the driver supply the voltage needed by the blu-ray diodes? If the driver is powered with 5V, the small voltage drop inside the driver will make it fall below the voltage needed by the diode, so it can't reach the set current. Try supplying the driver with a little higher voltage, say about 1V extra.

Thanks for the reply, but this driver boosts the voltage to the level needed by the diode, so if there is a small difference needed it will be met by the driver. That's one of the main reasons that so many enthusiasts are quite willing to pay $23 for these little gems.

The problem here is that a couple of us are not able to set our particular drivers at the current (mA) values we expect. This could be due to our own mishandling, as they are TINY and ESD sensitive. We are hoping that some experienced guru will show us the light so we can experience full power ( without having to cough up another $23). And since I've done several of these successfully, I'm wondering if perhaps other users have had and SOLVED this issue in the past. I am looking for their input on a possible solution.

 

[MrLWJPDX]

Amen.:angel: