lazeerer
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I finally de-canned the NUMB44 diode I had with a window problem today, it doesn't want to put out more than about 5.75 watts through a S1 lens, backing it down to about 4.5 amps produces about 5.5 watts out of the lens. I was trying to put it in a host today but the 5000 mA SXD driver I bought would not adjust over about 3.5 amps, then the metal top of the adjustment resistor fell off, Arg!! It's so tiny I can't see how to fix it, I probably wrecked it pushing on it too hard trying to reach higher than 3.5 A where it hit the stop, or maybe I just pushed too hard lacking the right sized tool. Would be nice if they came with a proper sized adjustment tool. Anyone have a tip for me how to rescue this driver less installing a new pot??
The output power meas. at 4.5 amps was when later running the de-canned diode off of a CC lab power supply. A peek at my small laser test setup below:
Pic
Pic
This photo is a mock-up without taped wires... During testing the driver did not get hot, the small copper heat sink probably isn't enough for a duty cycle of more than a few seconds so I kept the amount of on time to short tests..
Note: ALL driver adjustments were small & made with power OFF, then turning back on to see the new LD current level. Both diode and driver heat sinked, only running long enough each time to get a laser power output measurement and turning back off before adjusting again. Power on-off was through pushing a momentary on-off switch feeding the driver input, not turning the power supply off and on which could easily destroy the diode through power up spikes. One member advised against inserting a DMM in series with one of the laser diode leads to measure the current as he believes this can cause problems.... so maybe that isn't the way to do this. I do have a diode tester, just have to take it out of the box and use it.
Your issue is the way you where trying to set the driver and all your connections. Your DMM leads or leads you where using are way to long and the connection is not good. This is why you could not get over 3.5A
With today's drivers of High Current settings of ~5A the most easiest way to set the driver around this current is to only use a 1 ohm resistor across the LD-/+ as the load to set the driver. No diodes on your testload should be used as on most testloads that people use on this forum the load will become too high at thease currents.(Most Common Testloads that use 1ohm resistors that is..)
A 1 ohm resistor will give you ~4.5V-5V at ~5A.... So the best way to set the driver is use a 1 ohm resistor with Short leads and thats it... Its perfect for these diodes since these diodes also putout a load of 4.5V-5V.
Those leads coming off the driver (Look like 22AWG) in your image would be perfect alone. Nothing longer then that. With 22AWG wire you should not have longer then ~6-8" inches of wire going from the Driver to the diode. The shorter the better.
So if you have a High wattage 1ohm resistor just solder that only (No Laser diode connected) across the LD-/+ output of the Driver then Take your DMM and put it on 20V DC and attach your DMM leads across the 1 ohm resistor. (Make sure to not be in 10A setting.) Then Adj the pot to the current you want.
Thats all you got to do.
I like to use these:
Hot Sale Gold Electrical Chasis Mounted Aluminum Resistor 1 Ohm 5 100W WD | eBay
PM incoming about the broken Pot for replacment..