capacitor discharge

[freighty200]

Hi all again, after finding out why my welder creates the small spark when i finished welding ,( bleed resister on the output capacitor - thanks again,) i decided to first do a bit of research as to what it was and looked like and then to look in the case to see if i could id where it was.Well I'm not sure but have taken some photos to see if anyone can help, think its the small finned orange coloured thing with a wire connected to the+wire on the capacitor .whist looking at this i see the large wire + on the capacitor terminal looks a bit frayed but how do i discharge it so i can safely change the wire?

 

[xmetal]

The orange finned device is a diode assembly. The capacitor is the cylindrical device shown in the bottom photo. You don't want to short it out directly without having a resistor as capacitors don't like a full short such as a screwdriver across the terminals as this can damage them. You need to have a resistor (around 2k should do) in the shorting path.

+ pos terminal -----------------2k resistor----------------- - neg terminal

 

[freighty200]

Ok thanks, i suppose i could always put a meter on the capacitor on high dc reading i presume? To see if any charge is present.The orange diode was a guess as i didnt know what that was , initially i thought it might be on the pcb but then doubted that anything on the board would be big enough. Just out of interest how does it discharge the residual current if it hasnt got a bleed resistor fitted other than touching the torch on the work

 

[julianf]

I took apart a microwave oven yesterday. The cap was 2100vac. I was a little disappointed at its discharge rate, until i realised there was an internal 10meg resistor.

 

[freighty200]

Ok i'll post some pics . Its not that its a problem to touch to earth return its just annoying when you forget.