Capacitor Mod on Astro pocket turbo 130

[bunkclimber]

Originally Posted by Hobweld

I don't like having a charged capacitor in there... I mean I know enough not to touch it but it's the someone else factor.
Ken

Ken, a simple blob of silicone RTV on top of the capacitor terminals will keep any errant fingers off the terminals..easy to remove if you need to work on it.I'd be more worried about the open wiring chafing on that hole in the case with no grommet or bushing..

[GWIZ]

Originally Posted by Hobweld

The resistor remained in one piece this time and drained the capacitor in a reasonable amount of time. Welding pics to come this weekend.

Ken

False sense of security.

You are using a 100,000 uf capacitor and a 10k resistor if you use the RC calculator below you will find out that the cap will take 1000 seconds to discharge 63% of its capacity and around 5000 seconds to discharge to 99%, that would be 84 minutes.

If its discharging any faster, then I would assume there is other loads in the circuit contributing to the discharge rate.

If something goes wrong and you lose the other load the 10k resistor may not discharge the cap as quickly as you assumed.

RC time Calculator (this link is temperamental for some reason).
http://www.cvs1.uklinux.net/cgi-bin/...time_const.cgi


The ohms Calculator below can help you establish the wattage of the resistor.
Enter the resistance and the voltage, hit the tab and the wattage will be calculated.

The calculations is the wattage of the circuit so the resistor has to be rated above that, usually the next largest value sold.

Note, that the gold heatsink styles are meant to be mounted so the heat is pulled away by a secondary heatsink something.


Ohms law Calculator.
http://www.angelfire.com/pa/baconbacon/page2.html