This method is not a general rule because some optocouplers or gate drive optocouplers have characteristic differ than those in video, some times the output is open circuit inside or the led has not enough light to emitting to run the base. so you should remove it and test it with two digital multimeter or make a simple circuit as recommended in the datasheet.
Thanks for showing this quick and easy method of testing optocouplers with a multimeter. As others have pointed out a more detailed test could be done which entails desoldering the chip...ugh. Cheap optocoupler testers can be bought online...someone needs to do a review of these.
Q) It the transistor is damaged/open, you would also get no reading on Pins 3+4, so wouldn't you also need to test that the emitter and collector connect when the diode/LED illuminates the photosensitive base? Thx.
I'm a total electronics moron - but why others are using some more complicated methods of testing opto-isolators eg. one guy desoldered from the board and connected all 4 pins and use a resister and battery etc. Can I test an opto isolator "your way" directly on a board? (no desoldering involved). Thanks
It gets complicated. In circuit, no soldering, you may get readings from other components in the circuit. This is a good base test to show shorts or opens on the opto. Of course a short elsewhere in the circuit will show a short on the opto.
I recommend 1st to read the marking, and internet search the number(s) you find. If you have more knowledge... Optocouplers are a non-contact way to connect 2 circuits on a PCB that may be operating at different voltages, so look at the PCB circuits and see if the device appears to be "isolating" the two circuits. The transistor side (pins 3+4) are acting like a switch for the 2nd circuit. Similar to how a "relay" works ... just using light to activate vs using mechanical means.
Hi. I Dndid the same like you. I testes the diode-OK. When I test the transistor part, I get around 1 volt. But when take it out from the board, I then get nothing. Is that OK? How should it be tested?
1000 what? there is no 1000 there unless it is mV; is it? thanks because you're testing them in circuit, do those readings depend on the circuit or not? thanks
Thank for your efforts in explaining how to test Optocouplers
So nice of you
👍Cheers from algeria
Thank you brother
This method is not a general rule because some optocouplers or gate drive optocouplers have characteristic differ than those in video, some times the output is open circuit inside or the led has not enough light to emitting to run the base. so you should remove it and test it with two digital multimeter or make a simple circuit as recommended in the datasheet.
Thanks for showing this quick and easy method of testing optocouplers with a multimeter. As others have pointed out a more detailed test could be done which entails desoldering the chip...ugh. Cheap optocoupler testers can be bought online...someone needs to do a review of these.
many many thanks ❤❤❤
Awesome explaination.Thanks brother.Pakistan
My pleasure
Thanks for the detailed explanation.
You are welcome!
Toujours aussi efficace
Q) It the transistor is damaged/open, you would also get no reading on Pins 3+4, so wouldn't you also need to test that the emitter and collector connect when the diode/LED illuminates the photosensitive base? Thx.
Genius explanation. Thanks a lot. 🇪🇹
Glad it was helpful!
Nice work, please i need a detailed video on how to use digital multimeter for a beginner
Noted!
Should 1100 come out without AC 220V power supply?
Brilliant,thank you 🙏
You're most welcome!
I'm a total electronics moron - but why others are using some more complicated methods of testing opto-isolators eg. one guy desoldered from the board and connected all 4 pins and use a resister and battery etc. Can I test an opto isolator "your way" directly on a board? (no desoldering involved). Thanks
It gets complicated. In circuit, no soldering, you may get readings from other components in the circuit. This is a good base test to show shorts or opens on the opto. Of course a short elsewhere in the circuit will show a short on the opto.
How do we know is it optocoupler or an IC by doing it visualy when it still on circuit?? Is it any sign?
I recommend 1st to read the marking, and internet search the number(s) you find. If you have more knowledge... Optocouplers are a non-contact way to connect 2 circuits on a PCB that may be operating at different voltages, so look at the PCB circuits and see if the device appears to be "isolating" the two circuits. The transistor side (pins 3+4) are acting like a switch for the 2nd circuit. Similar to how a "relay" works ... just using light to activate vs using mechanical means.
Can this be used to reset a Z80 cpu, by connecting the collector to ground and the emitter to the /RST pin?
Helpful! Thx for your video.
So welcome
Hi. I Dndid the same like you. I testes the diode-OK. When I test the transistor part, I get around 1 volt. But when take it out from the board, I then get nothing. Is that OK? How should it be tested?
Thanks
Welcome
you are very good to expain but please change your mic
Oh..Great ..Thanks you soo much ..
You are very welcome
Great!Great!Great!
1000 what? there is no 1000 there unless it is mV; is it? thanks
because you're testing them in circuit, do those readings depend on the circuit or not? thanks
Thanks
Welcome
In case I need help in one cicuit, can you help and give explanation?
You are very welcome Pierre, Join me on Patreon Page for more unique content
good
Thanks
Very nice😋👏!!! Don't miss out = "Promo sm" !!
Thank you