If you don't see the LED light up in either orientation, then keep in mind it could be IR instead of dead. You can use most digital cameras to determine this because they can see the IR light.

Identify a characteristic of LED bulbsmilady

I just happened upon this tutorial which answers the problem of sorting the colors for your clear LEDs. Use a microcontroller to switch back and forth so you don't need to worry about polarity. It won't tell you the forward voltage and current specifications, but those would be difficult to actually tell in any case. All you'll really be able to tell is when it turns on, if you go over current you'll likely only know when it's already too late for that LED. If you had known duplicates, this information would be useful, but if each one is its own sample then it's pointless.

Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Identify a characteristic ofsoft gels

Just about all LEDs can take at least 20 mA. This is almost certainly true of anything in a discrete leaded case, like T1-3/4 or T1. Some small SMD parts may be rated for less.

Identify a characteristic of LED bulbsquizlet

I have several hundred clear LED's of mixed colour and would like to sort them and determine their characteristics so I can use them. As far as my research tells me, there is no way to determine the forward current of an LED directly, and in order to determine forward voltage you need to know forward current. My question is, how do LED manufacturers determine these values, and is there any way I can do the same?

Rig up a jig to show the voltage across the LED. Since the power voltage and resistor are known, you can calculate the current from this too. This will give you one datapoint for voltage and current, which should be good enough for most purposes.

I would use a 5V supply with a 330 Ω resistor in series. You are very unlikely to have LEDs that can be damaged by this. This will put at most 10 mA through the LED if you get it in the forwards orientation, or 5 V in reverse accross it for the backwards orientation. Neither should hurt ordinary LEDs. 10 mA will be enough for even inefficient LEDs to light up visibly on the bench (assuming typical indoor conditions).