Current discharge re capacitors

[Robin Hooper]

Hello everyone, I know this may be a very elementary question but I'm not an EE or have access to one other that this forum.

I've been reading up on capacitors and so far I'm not able to decipher if a cap will discharge only if the capacitor has reached its maximum capacity. I would think that it would discharge when the two leads are connected in one form or another regardless of its capacity. To connect the two leads can be is very dangerous, hence this post. I can only find that a cap will discharge very quickly and only discharge a percentage of the stored energy. What I'm trying to do is charge up a cap by inducing a coil with a spinning permanent magnet within the coil. This would then load the cap to its maximum voltage and then have it discharge only when it has reached its maximum capacity. A resistor and diode will also be located before the cap to prevent over loading and ensure direction of current flow. Note: Do correct me if I don't understand the safe/proper circuit involved.

Thanks again everyone that have responded to previous posts and this one as well.

 

[Robin Hooper]

After posting the previous question I was redirected to the forums capacitor page to find that DC current will only charge the capacitor to its maximum and effectivly close the circuit letting the DC current flow through. To clarify the magnet essembly is mounted inside the coil on a shaft that is so designed to be the commutator, turning the DC current on and off as the rotor turns.

 

[Studiot]

Within the voltage rating of a capacitor, the voltage it charges to is dictated by the charging voltage and circuit, rather than by the capacitor.
So long as the circuit can supply enough charge, capacitors of different values (capacities) will be charged to the same voltage by the same circuit.

And yes a capacitor can be discharged again at any degreee of charge.
Also it may only be partially discharged.
Also the charging can stop and start as can the discharging. Capacitors perform like this in many working circuits.

hope this helps