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Name: Aaron
Status: other
Grade: 9-12
Location: DC 
Country: N/A
Date: 7/9/2005


Question:
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.


Replies:
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.

Ryan Belscamper



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