Hi. I have a passive buzzer and i need a piezoelectric one for my project so how do I know if its piezo electric? btw its from the elegoo uno r3 kits (passive one).
Does it look like this?
1 Like
If you connect it between 5v and GND (0V) and it does not beep, it’s passive.
If you measure the resistance with a DMM ( Ω meter) and the resistance is very very high it’s a piezoelectric buzzer.
1 Like
yes
i got 1500 res
It's an active buzzer, then. Does it have a (+) symbol anywhere? (see reply #2)
1 Like
yes and its passive not active thats what it said
I don't take Elegoo as an authority on anything. If it has a (+) symbol, it's to orient it correctly for the application of DC power. It's active.
Both active and passive piezo speakers are, well, piezoelectric. Try applying 5V to the (+) and ground to the other contact. What happens?
Even though they are sometimes advertised as "piezo buzzers", my experiences is that the ones like in the picture I shared are electromagnetic. I took them as advertised up to the moment I discovered a coil upon opening one up after someone here questioned me on me calling them a piezo.
I suppose polarity might be important in the case of a stereo application to avoid phase cancellation, but it's probably highly unlikely to ever see such a component used in a stereo application. Or maybe it's only so they can use the same mold for the cases of the active and passive buzzers. All of mine have this polarity marking.
1 Like
Ok I found another buzzer and this one instead of epoxy has a green circuiut board underneeth
I measured this one and I was getting somewhere in the hundreds and 40's and 20's and literaly where not. BUT it was beeping and the only time I've experienced my multimeter beeping before is when both spikes touch each other. However, when there wasn't a beeping noise, it showed a number in the hundreds.
Please reply as to the test in post 8
When I tested it, both of the buzzers didnt do anything
it didnt do anything
I also tried it with different batteries
It didnt beep. I tried with both buzzers so both buzzers are piezoelectric???????
5V?
Those generally go 'beep' if you apply 3.3VDC or higher to them.
Once more... all those speakers are piezoelectric. The passive is piezoelectric and the active is piezoelectric. The active one is a piezoelectric disc with a driver, combined in one housing.
How do you know?