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I'm working on a project where I may need to open and repair an old device that probably contains some high-voltage capacitors. Would it be relatively safe to d

I'm working on a project where I may need to open and repair an old device that probably contains some high-voltage capacitors. Would it be relatively safe to do this if I was wearing rubber gloves + shoes, and used a multimeter to check for voltages, and a large resistor to discharge any capacitors? What kind of bleed resistor is typically used, e.g. for old TVs?

eurasiantiger 5y ago
Just short the positive side to ground to discharge them. Note: do NOT do this with thin wires and large capacitors / arrays of capacitors, or you may get a hot copper shower.
- jstanley 5y ago
  Preferably connect it to ground through a resistor.
amelius 5y ago
This might be a nice feature of a multimeter: discharge mode. Putting the leads over a capacitor, the multimeter will show the voltage and discharges the capacitor with a constant safe current. Beeps can be used to indicate when the capacitor is safe to handle or not.
- prewett 5y ago
  It kind of already has a discharge mode, just short the leads of the capacitor with one of the probes.
  - amelius 5y ago
    That is not how you properly discharge a capacitor, though. Especially big ones.
barbegal 5y ago
If it's 250V or less then that's probably overkill. Rubber gloves alone will protect against a few hundred volts. Bleed resistors depend on the capacitor size but are usually in the high kilaohms.
_fizz_buzz_ 5y ago
> a multimeter to check for voltages, and a large resistor to discharge any capacitors That's all that I use. Don't hold the resistor in your hand though, depending on the size of the capacitor they can get quite hot. I usually use some pliers to hold the resistor.