Need Help with a capacitor

[Smirk88]

Hi Everyone,

I'm new to this forum and I have little knowledge of how capacitors work. I am currently trying to replace what looks like a blown capacitor in my denon receiver. It's a 100uf 200V capacitor. The top of the capicitor is somewhat open and it looks like some material is sticking out through the top. I was wondering does this capacitor still need to be discharged as I really dont want to shock myself and I'm not sure how powerful a capacitor with this rating is? Is 100uf 200v lethal? If not I was thinking of buying some insulated screwdrivers to test the charge in it? Any help would be greatly appreciated. Thanks and sorry for my noob questions like this.

 

[JimB]

Is 100uf 200v lethal?

Unlikely for a healthy person.
But it will give you a "bit of a nip!"

I was wondering does this capacitor still need to be discharged

Probably not.
After a few minutes it is most likely that the cap will have discharged through the receiver circuitry.

If you had a multimeter, you could measure the voltage on the terminals, just to be sure.

In the absence of a meter, just short across the two terminals for a few seconds using a screwdriver blade.

At the risk of stating the blindingly obvious, make sure that the thing is not plugged into the mains before you do this.

JimB

 

[Smirk88]

Thanks JimB for your info I really appreciate it. I feel more confident in actually touching this thing now that I know it wont kill me I'm going to my local harbor freight to pickup some insulated 1k volt rated screwdrivers. Thanks again!

 

[unclejed613]

After a few minutes it is most likely that the cap will have discharged through the receiver circuitry.

or through itself.... it's not much of a capacitor at this point. but it's always good to check anyway. get in the habit of checking for stored voltages on caps before doing anything else. keep a 10k 5 watt resistor (it's best if you have alligator clips connected to it) on the workbench for discharging caps. i have a resistor on a dual banana plug, which fits in the banana plugs of my DMM. i plug it in across the probes and then touch the probes to the cap, so i can watch the voltage. when you get down to between 2 and 5 volts, that's usually safe enough to handle the board without worrying about getting bit.