# HV capacitor discharge?



## FireInTheWire

Hello everyone, what is the safest way to discharge a capacitor? I have a 6200 V capacitor of unknown status from a microwave that I need to discharge for my Tesla coil. I've got little experience with capacitors as yet.

Thanks!


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## nolabama

big resistor with gloves, and safety glasses


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## erics37

Screwdriver shaft.

:whistling2:

EDIT: Okay I thought better of it. Don't use a screwdriver shaft.


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## nolabama

erics37 said:


> Screwdriver shaft.
> 
> :whistling2:
> 
> EDIT: Okay I thought better of it. Don't use a screwdriver shaft.


it will work :thumbup: only problem it will melt the tabs on top of the cap
its how i discharged em for a while 

the best/safest way would prolly be using your wiggy/analog tester to read the voltage....but 6200v i dunno i never effed with something like that cant be no bigger than a tasser pop can it?


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## joethemechanic

erics37 said:


> Screwdriver shaft.
> 
> :whistling2:
> 
> EDIT: Okay I thought better of it. Don't use a screwdriver shaft.



Real men use their finger


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## erics37

nolabama said:


> it will work :thumbup: only problem it will melt the tabs on top of the cap
> its how i discharged em for a while
> 
> the best/safest way would prolly be using your wiggy/analog tester to read the voltage....but 6200v i dunno i never effed with something like that cant be no bigger than a tasser pop can it?


I think the resistor is the best idea. Or just let it discharge naturally if there's no big hurry.


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## erics37

joethemechanic said:


> Real men use their finger


I don't need to hear about your self-stimulation methods.


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## joethemechanic

In high school we use to yell catch and toss them to a new kid. But then again, we already knew what their charge status was


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## FireInTheWire

erics37 said:


> I think the resistor is the best idea. Or just let it discharge naturally if there's no big hurry.


So should I hook the resistor onto a wire that's connected to a hot stick or something? Or I have some fiberglass glow rods...

I'm sorry, it's actually a 2300 V capacitor, not 6200. It was probably wishful thinking on my part .


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## HARRY304E

FireInTheWire said:


> So should I hook the resistor onto a wire that's connected to a hot stick or something? Or I have some fiberglass glow rods...
> 
> I'm sorry, it's actually a 2300 V capacitor, not 6200. It was probably wishful thinking on my part .


Read this...http://www.repairfaq.org/sam/captest.htm#ctsdc


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## FireInTheWire

HARRY304E said:


> Read this...http://www.repairfaq.org/sam/captest.htm#ctsdc


This was good. Thanks!


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## NWsparky

One of the building engineers I have worked with used a heat gun he said to discharge before, it also works for equalizing a UPS strings voltage before initial hook up to DC plant (just FYI)


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## Zog

FireInTheWire said:


> Hello everyone, what is the safest way to discharge a capacitor? I have a 6200 V capacitor of unknown status from a microwave that I need to discharge for my Tesla coil. I've got little experience with capacitors as yet.
> 
> Thanks!


Um, a discharge stick?

http://www.mitchellinstrument.com/s...orting-probes-capacitive-discharge-tools.html


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## nolabama

Zog said:


> Um, a discharge stick?
> 
> http://www.mitchellinstrument.com/safety-and-personal-protective-equipment-ppe/electrical-grounding/shorting-probes-capacitive-discharge-tools.html


Is a shorting probe different than a grounding means? They look like tbe same thing.


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## Zog

nolabama said:


> Is a shorting probe different than a grounding means? They look like tbe same thing.


What is a "grounding means"?


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## FireInTheWire

Zog said:


> Um, a discharge stick?
> 
> http://www.mitchellinstrument.com/safety-and-personal-protective-equipment-ppe/electrical-grounding/shorting-probes-capacitive-discharge-tools.html


Couldn't I just make my own with a hot stick, a capacitor and wire?


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## FireInTheWire

FireInTheWire said:


> Couldn't I just make my own with a hot stick, a capacitor and wire?


I mean a **resistor** and hot stick and wire. Too early for electrical discussion.


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## Zog

FireInTheWire said:


> Couldn't I just make my own with a hot stick, a capacitor and wire?


What would it be rated for?

For small caps on a bench it really does not matter, for discharging MV power systems (Cables for example) it needs to be properly rated.


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## den

I could be wrong and if I am I doubt that I will hear about it!!!! the capacitor will only be charged up to what ever voltage is applied so it might not be thousands of volts you are discharging. I thought microwave caps already had discharge resistors on them but you can solder one on and leave it there and it will automatically bleed down when it is not energized and not affect the cap when in use


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## nolabama

Zog said:


> What is a "grounding means"?


Those wires with the orange flages that the POCO puts on the wires before they work on them. I dunno what they are called, Im a dang ole inside wireman thats gotta work outside some.


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## den

nolabama said:


> Those wires with the orange flages that the POCO puts on the wires before they work on them. I dunno what they are called, Im a dang ole inside wireman thats gotta work outside some.


I don't know what you are calling flags. We had 2 different types of cables- one has large insulated clamps that are put on by hand and screw tight. This is used as a jumper to keep the line energized while working on the jumper, pole, etc. they are not to be used for grounding. the other was for actually grounding and they had clamps that had to be put on with an insulated stick so we were not real close to the wire in case of problem like trying to ground an energized line by accident. Ours were #2 fine stranded min 6 foot length up to 10 foot. It couldn't be longer than the stick we used to hook it up with.


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## Zog

nolabama said:


> Those wires with the orange flages that the POCO puts on the wires before they work on them. I dunno what they are called, Im a dang ole inside wireman thats gotta work outside some.


Sounds liek you are refering to personal protective grounds. 
http://www.salisburyconfigurators.com/grounding/

The shorting probes have resistors in them for discharging stored energy.


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