Wiring up a filter copasitor?

For my Cold Fusion Project I was told to use a filter copacitor with the isolating transformer and the bridge rectifier.  I have had some trouble understanding this.  The mains AC runs through the isolating transformer and right after that I need to hook up the filter copacitior.  How do I know which is positive and negative.  I know AC alternates between + and - but when I need to hook it up to the rectifier I need to find + and -.  How do I do that?

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Bear in mind that the voltage and capacitance combination is quite capable of killing you at this point.
Capacitors don't kill people, people kill people. Or something like that.
If capacitors are outlawed, only outlaws will have capacitors.

You can have my capacitor when you pry it from my cold dead hand.
Re-design7 years ago
The filter CAPACITOR goes after the bridge rect. It is to filter out some of the ripple of the a/c turned into d/c by the rect.

You find the + by looking at the marking of the rect. or by using a volt meter.
Kalrag (author)  Re-design7 years ago
So is it maditory or is it optional that I use it?
If you want smooth DC, its mandatory.
Right. It depends on what you're doing with the dc. Since no one's actually gotten cold fusion to work, I don't know if you need pure dc or if you can use it raw.
orksecurity7 years ago
The bridge rectifier will have four connections. Two, the AC input, go to the output of the transformer. The other two are pulsed DC output; one positive relative to the other. If you're using a preconstructed rectifier, those pins are probably labelled pretty clearly; if not, you look at the specs for that component. If you're building your own bridge rectifier out of diodes, then if you understand diodes the proper connections should be moderately obvious. (And if you don't, you aren't ready to tackle this project.) Remember to that the capacitor continues to hold a charge after you unplug and turn off the device. That can be quite enough power to weld metal or kill you. if you or anything else happens to touch the wrong wires. Believe me, you do *not* want to win a Darwin Award for creatively removing yourself from the gene pool... and some of your questions suggest you're headed in that direction.
lemonie7 years ago

Who told you that? I'm interested as to what you're working from.