Current

How do I test the current a driver is out putting?

lazer said:

How do I test the current a driver is out putting?

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If the driver is not already connected to a diode, you connect a dummy load to it and measure it with a DMM. If it is already connected to a diode, you place the DMM in series with the battery to measure it. Let us know which case is true and we will help you through it. It would also help to know what driver it is.

Peace,
dave

Its not connected to a diode but I am going to hook it to a 150mw violet diode once I find the current.  I think the diode is a phr-803 as the seller said it was capable of 200mw with heatsinking. If I put a small 12vdc brushless fan on it from radioshack would that be enough to cool it?

lazer said:

Its not connected to a diode but I am going to hook it to a 150mw violet diode once I find the current.  I think the diode is a phr-803 as the seller said it was capable of 200mw with heatsinking.  If I put a small 12vdc brushless fan on it from radioshack would that be enough to cool it?  

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OH LORD!

Who was the seller?  He has GREATLY overstated the capabilities of the PHR-803T diode.  A [highlight]VERY VERY FEW [/highlight]PHR diodes can make it to 200mW.  I have been through literally 100's of PHR-803T diodes.  I have found a less than five that could take 200mW for any length of time.  If you want your diode to last a long time, you should limit it to about 115mW.  If you are willing to limit your use of it, you can get it to 150mW.

You also need to provide it with a heat sink.  A fan is nice, but you need the metal-to-metal contact to draw the heat away from the diode quickly enough.  Before you hook up the diode to the driver, build or buy a dummy/test load and set the current to no more than 120mA.  This should give you around 110mW.  A lower current will help your laser live a longer time.  Do not worry.  You can still "burn" stuff with only 70mW of focused violet laser light.  Then short the cap.  THEN hook up your diode.

Take your time.  Double check everything along the way.  If you need to ask more questions do so.  If it takes you a week to build this (it won't) you will still have a burning violet laser at the end.  If you hurry and mess up, you have a pile of parts to begin your next build with.

Peace,
dave

Sorry: I meant 150mw for some reason I typed 200mw.  How long would it last at 150mw?  How do I make a dummy load?  I will probably set the driver to 120ma to get 110mw because I want it to last a while.  What is the duty cycle on a 110mw laser is it about 2 minutes? I found a post on the fourm that says to hook a 1ohm resistor to the driver and check the voltage accross the resistor

lazer said:

How do I test the current a driver is out putting?

Click to expand...

If you are using DDL's driver then this post will show you how to test it's output current.

If you wish to buy the dummy load to test the driver, you can get them here.

How do I wire a violet 5v diode using 120ma of current to a 5v blue led indicator light using 30ma?  Do I wire it in a paralle circuit?

Put the LED between the battery and the driver with a 180ohm limiting resistor, you should never mix loads on the output side..... especialy when one of them is an expensive LD

Regards rog8811

[edit]just noticed, you say 5v LED, that would be 150ohm resistor
Also have added a simple test load you can build.[/edit]

Thanks that helps alot ;D