How Do You Build and Safely Discharge a Capacitor Bank?

[Learnphysics]

I'm thinking of building a Capacitor bank.I'm here to confirm that i just connect the capacitors in parallel with each other? Do i put the discharge terminals in parallel too, just like any other circuit?

How would i go about adding a feature to discharge all capacitors simultaneously? (by means of a switch).

Forgive my newbie questions, I've never built one of these before, and my knowledge of Capacitors is geared towards rectification circuits rather than build banks with them.

 

[schip666!]

Yup..."bank" means put'em all in parallel. Once wired in parallel, it will be kinda hard to not discharge them all at once since all their +/- terminals (presuming that you are working with largish electrolytic caps) will be connected together.

Be careful, you can get quite a jolt of power when discharging. If you just put a switch across the bank pins you'll probably invent the one-time-operation switch. For an educational example: Start with a fairly low charge voltage and a small number of capacitors. Charge them up, disconnect the charging current, and lay the shaft of a screwdriver you don't much care about across the terminals. Then extrapolate to the voltage and capacity you were thinking of using.

It's also a good idea to put a fairly high resistance resistor across the terminals so the bank slowly discharges when disconnected. Otherwise you can get quite a shock when you casually pick them up after they have not been powered for a while.

 

[davenn]

It's also a good idea to put a fairly high resistance resistor across the terminals so the bank slowly discharges when disconnected. Otherwise you can get quite a shock when you casually pick them up after they have not been powered for a while.

awwww that was the good ol' mean trick to do to the new trainee techs in the workshop
... leave a few charged caps lying around waiting for the unsuspecting ;)

cant do it these days with OH & S etc etc taken all the fun out of the workplace ;)


but on a serious note, I would like a better explanation from Learnphysics on what he meant by using a switch to discharge the cap bank.
Did he want the switch to discharge the cap charge into a specific cct in one burst
thats ok :)
but if he was wanting to just to short out the cap bank... then as you said .. a really bad idea !

Dave

 

[Learnphysics]

awwww that was the good ol' mean trick to do to the new trainee techs in the workshop
... leave a few charged caps lying around waiting for the unsuspecting ;)

cant do it these days with OH & S etc etc taken all the fun out of the workplace ;)


but on a serious note, I would like a better explanation from Learnphysics on what he meant by using a switch to discharge the cap bank.
Did he want the switch to discharge the cap charge into a specific cct in one burst
thats ok :)
but if he was wanting to just to short out the cap bank... then as you said .. a really bad idea !

Dave

I suppose what I'm going for is similar to what a flash camera does on a larger scale. (with more caps) So a switch that discharges the cap in a burst.