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Help setting current on Rkcstr - Thank you

tommii89

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Hey everyone,

I get my test load tomorrow from modwerx.

Pretty much, I want to know the following, (if someone can draw up a little picture that would be perfect).

I have my DMM -
digital-multimeter-06.jpg

  • What setting do I set it to?
  • How do I connect the test load to the rkcstr driver?
  • And where do I connect my DMM to?
  • And how do I literally SET the current?

I'm setting the current to 365mA (open can red LPC)

Thanks in advance

Peace,
Tom
 



bobhaha

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Well assuming you have a micro-driver V3 (aka Rckstr driver)

Here is the link for all your info! http://rkcstr.googlepages.com/MD_v3_inst_rev1.pdf

In regards to the Modwerx dummy load (which i will be buying very soon!) there is an onboard resistor of 1.0ohm to allow you to measure the output current, which is equivalent to the voltage across the resistor, where 1mV is roughly equivalent to 1mA of current.

So you would have to set the DMM to DCv 2000ma simple.. in the picture it is the one on the left side. I'm not 100% sure but there are two small holes on the dummy load i think IIRC you put the probes of the DMM in to the holes and you get ur reading... other wise that PDF document will tell you how to do it from the driver and you dont need the dummy load (but it is not as accurate!).. but Modwerx is great.. you shouldn't have any problems with them!

hope that helped -Adrian
 
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tommii89

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I set the DMM to 2000m like on the top picture on the left side - measured my + and - diode connections and it doesnt go over "60" on the DMM

What does this mean?

Tom
 

tommii89

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Nevermind - It won't work properly without the test load anyway.
 
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bobhaha

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Yeah it won't work with out a dummy load.. is this the V3 or the fixed current driver.. do you have a link just to make sure?
 

bobhaha

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yep that simple.. attach the load + to +, - to - then use the DMM in series to test the current.. not sure if you put it between the - DMM - or if there are probe holes on the dummy load.. ask ndrew2505 for a print out on how to use it.. he is the owner of the modwerx website! any other problems pm me!

good luck -Adrian
 
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tommii89

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It says this on the dummy load

1. set voltage range
2. connect to driver
3 power driver << -------- WHAT DOES THIS MEAN? HOW??

Tom
 

bobhaha

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I'm guessing it just means to connect to a power source and turn it on.. (connect the driver and turn on the "laser" eg press the on button at rear of laser/complete the circuit!).
 

ndrew2505

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all the dmms ive used have a 2v setting and thats what i use to measure the ma. since you dont have one try the 2000m or 200m and see what happens. turn the pot all the way down(counter clockwise) and when you test it should be around 25-30ma..

also make sure your using 7.2+v for the rkcstr driver...
 

bobhaha

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well you are supposed to set the DMM to more then what your expected output will be.. in this case you could turn it all the way down.. then go up. Or you could go straight to the 2000m and measure from 0-2000ma ... which would be the safest way to measure it, if you dont know what your doing... just so you don't blow the fuse in you DMM.

like ndrew said.. if you had the 2v setting that would be even better.. my DMM has it.. maybe cause its not a cheapy. :D

BTW ndrew would you know what the MAX input is of a Rkcstr driver during load? if i have a LD with say a 1.5v drop.. could i hook up a 12.5v power pack?? the max input voltage IIRC is 12v but if i had a LD with 1.5v would that = 11v ??
 

ndrew2505

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max voltage for a rkcstr is ~16v if im not mistaken. my dmm is a radio shack cheapy i bought for 20$ and it has a 2v setting so cheapness isnt a factor. ive also got one from dx that cost ~10$ and it also has a 2v setting..
 

bobhaha

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oh ok.. i thought it was 12v.. kk nvm i won't have a problem then!! well the ones i used to have were $5 cheapys and they were simular to the ones shown in the pic above! i got them from ronies! LOL.. thanks for the info!
 

tommii89

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I set the current, but i assembled the laser and It's not working people. You can I send it too to fix/build it. I think I've fucked it..

Please let me know if you know someone that can do it free or cheap..

Thank you.
 

bobhaha

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well what did you do.. did you attach LD yet? what steps did you do?
 

ndrew2505

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I set the current, but i assembled the laser and It's not working people. You can I send it too to fix/build it. I think I've fucked it..

Please let me know if you know someone that can do it free or cheap..

Thank you.

pm me...
 




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