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how to tell which is hot or cold on a diode that is already sealed

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i bought a 200 mw green, and a 150 watt red diode, that is already inside of a heatsink.
one has a red and black wire coming out of it,and the other one has a orange and white wire coming out of it.
how do i know which one to connect the positive wire to, and which one to connect the negative wire to.
and how do i know how much power to use?
3 volts or 5 volts.
they did not come with any data.
bought them off of ebay with a set of scanpro20s.
any help would be greatly appreciated.
thanks and God bless.
 

Eudaimonium

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Sorry? Hot and cold? Might want to pick thread title more apropriately.

Anyhow, it is sure not 150 W red diode, it's maybe 150mW (miliwatt) diode.

If your diode does not havy any sort of current regulation circuit inside, you need to contruct your own in order to power it without frying it.

Can you give us a link to where you bought those, it would be of help?
 

Eudaimonium

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sorry i haven't figured out exactally how to post and reply yet. don't mean to offend anyone.but thanks for you reply and God bless you.
 

Benm

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Obviously he meant positive and negative, and there is a pretty safe way to tell using a battery or dc power supply, resistor and a multimeter:

Run a 1k resistor from the positive terminal of the battery, connect the multimeter in series on current range (suggested: 2 or 20 mA). Hook that up to one lead of the diode, and run the lead to the batteries negative terminal.

In the proper direction, some current should flow, while in the other it shouldn't conduct at all.

I'd suggest using a 5V power supply, or batteries adding up to about that voltage. 6 volts should also be okay, but keep it as low as possible as laser diodes arent rated to withstand large reverse voltage.

In the good direction it should measure in the order of 0.4mA. Obviously the laser will not light up at that current, but the difference in current draw should be very obvious between the correct and reverse polarity... provided there is no other 'stuff' in there but wires going straight to the laser diode.
 
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thanks so much for your help i will try that you don't think it will burn out my diode do you?thanks and God bless.
 




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