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Electronics => Beginners => Topic started by: Hextejas on March 08, 2018, 11:01:19 am

Title: Continuity test on a LED bulb ?
Post by: Hextejas on March 08, 2018, 11:01:19 am
Can I do this as a test to see if they are any good ? That is what I do with an incadescent bulb.
Title: Re: Continuity test on a LED bulb ?
Post by: Nusa on March 08, 2018, 11:19:58 am
Can I do this as a test to see if they are any good ? That is what I do with an incadescent bulb.

I'd say no, that's not a useful test for LED assemblies, as a rule. Plug them into their designed environment if you want to see if they work.

Even if you only want to test an individual LED component, remember that it's a diode and should only pass current in one direction.
Title: Re: Continuity test on a LED bulb ?
Post by: Audioguru on March 08, 2018, 11:32:16 am
I use the "diode test" function of my multimeter to test an LED. Most LEDs but not white, blue and bright green show the forward voltage and light up at the fairly low current in the test.
Title: Re: Continuity test on a LED bulb ?
Post by: Chris-IP5 on March 08, 2018, 05:42:12 pm
I use the diode test function on my digital meter.

Red probe connects to anode and display reads forward voltage, also lights the LED.

I just tried the continuity function. It did light the LED (red probe to anode). The display read OL and there was no beep. So still useful to identity which lead is which but more info from using the diode test function.
Title: Re: Continuity test on a LED bulb ?
Post by: ebastler on March 08, 2018, 10:28:23 pm
I use the "diode test" function of my multimeter to test an LED. Most LEDs but not white, blue and bright green show the forward voltage and light up at the fairly low current in the test.

I think the OP is not asking about an individual LED, but an LED-based bulb for use at mains voltages. For these, neither continuity nor diode test mode of your multimeter will tell you much. As Nusa said, screw it into a socket and see if it turns on.