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steve9983
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How can you determine the polarity an electrolytic capacitor (if it is indeterminable from a visual inspection)
Did you discharge the cap after the first measument?berkeman said:... I just tried it in the lab and got a negative resistance with two different DVMs -- I'm not sure where the negative sign is coming from, but whatever...
Yeah, I tried that. Then tried a 2nd capacitor in the reverse polarity first. I'll have to figure this out sometime (no time now). Thanks, -Mike-dlgoff said:Did you discharge the cap after the first measument?
berkeman said:Yeah, I tried that. Then tried a 2nd capacitor in the reverse polarity first. I'll have to figure this out sometime (no time now). Thanks, -Mike-
Not always. I've seen some mislabeled electrolytics. Yikes. Always wear your safety glasses when you power up a new circuit...frogdogbb said:It is possible that it is a bi-polar cap so orientation is not important. Unless it is really old polerised electros almost always have a stripe running vertical on the case or horizontal for an axial, indicating the negative side. The positive side always has a longer lead.
Yeah, big pop/boom. I'm not sure of the mechanism, but I've been there when it happens. That's one of the reasons that electrolytic caps have scored metal tops -- to help aim the blowout.rachmaninoff said:What happens when an electrolytic cap fails? Does it explode? Does the aluminum combust or oxidize? Are there any pictures of what happens?
A capacitor is an electronic component that stores electrical energy in the form of an electric field. It is made up of two conductive plates separated by an insulating material.
Capacitor polarity refers to the direction of the electric field within the capacitor. It is important to determine polarity in order to correctly connect the capacitor in a circuit.
The polarity of a capacitor can be determined visually by looking for markings on the capacitor itself. The positive terminal is usually marked with a "+" symbol, while the negative terminal may be marked with a "-" symbol or a stripe.
If your capacitor does not have any markings, you can use a multimeter to determine polarity. Set the multimeter to measure resistance and touch the positive lead to one terminal and the negative lead to the other. If the resistance is low, the leads are correctly connected. If the resistance is high, reverse the leads and the resistance should be low, indicating the correct polarity.
Yes, there are other methods for determining capacitor polarity, such as using a diode tester or a circuit diagram. It is important to always confirm the polarity before connecting a capacitor in a circuit to avoid damaging the component or the circuit.