Discharging Capacitors for Disposal
I would like to know what is the best way to discharge a
capacitor, when recycling televisions and monitors. I was told just
cutting the wire leading from the CRT tube to the capacitor will work.
Also where can I find further information on this matter.
Capacitor discharging is usually done with a grounding rod. (imagine a
plastic rod with a stout conductive piece of metal at the end) Once the rod
is in contact with both leads on the capacitor, it is known to be
discharged. (assuming you're bright enough to have disconnected it from
whatever the original charging source was in the first place) Next, a wire
is connected between the leads of the capacitor, to prevent it from
charging. The trouble is, normal background RF (radio signals and such) as
well as static electricity CAN in some cases begin charging capacitors,
slowly, over a great deal of time. A shorting wire prevents this.
Since you mentioned the CRT tube as well, I think it is worthwhile to point
out that these also need to be safed for disposal. At the back of the CRT
is a small plastic plug, or in some cases a sealed glass tube. Removing
this plug or breaking the tube allows the CRT to fill with air, thus
preventing it from imploding if shattered. Depending on the type of tube,
other precautions may apply, due to possibly hazardous materials used in the
electron gun and screen.
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Update: June 2012