why +ve terminal of electrolytic caps must be connected to +ve of battery?

[dexterdev]

Hi all,
I have a doubt regarding electrolytic capacitor. Why the electrolytic capacitor should be connected to higher DC potential in the circuit. What happens if the opposite happens? Also how electrolytic capacitors must be used where varying voltage comes across it?

-Devanand

 

[(*steve*)]

Why the electrolytic capacitor should be connected to higher DC potential in the circuit.

Because they're a polarised component and work properly within certain parameters, one of which is the polarity of the voltage across them.

Note that there are non-polarised electrolytics which can be connected either way around.

What happens if the opposite happens?

Something between nothing and *BOOM*.

many electrolytics can withstand a small reverse voltage without significant harm.

However when operated with the incorrect polarity, you will almost certainly have a much larger leakage and lower capacitance.

Also how electrolytic capacitors must be used where varying voltage comes across it?

As log as the voltage varies from zero to the rated voltage it's fine. Problems occur when you exceed the maximum voltage or you have a significant reverse polarity.

 

[dexterdev]

thankyou sir for the reply