Contuinity question

demogo

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Quick question.

I wired something up tonight with a 22uf "filter" cap installed in it.

Should I be able to do a 'continuity check' or do a resistance check from one side of a circuit that has this cap installed in it to the other (with the cap in the middle)?

I get no continuity with the circuit with the cap installed and with the cap bypassed I get continuity.

I went ahead and plugged it in anyway in the game and it worked with the filter cap installed in the circuit so I'm betting that the cap is interfering with the continuity check?

Thanks!
 
So my "filter cap" is filtering my DMM double checking. :)

Thanks Mod!
 
Well, not exactly. You probably would have gotten a climbing reading to infinity (as far as your meter knows) if you had the negative lead of your meter on the negative leg of the cap, and the positive lead on the other leg.

Caps shouldn't show continuity through, unless they're bad. And you have to pull them to test that, as other parts in parallel will give false readings...
 
If you're trying to check the "goodness" of your soldering, put a lead on either side of the joint (forget the capacitor). for example, put one lead on the wire coming from the capacitor, and the other on a pad on the other side of the solder joint (preferably not on the joint being tested itself).

Some DMMs have a capacitance test setting you can use for a capacitor. I have a Fluke 115 and I love it. The diode test setting is good for testing transistors as well.
 
Thanks guys.

I checked it at all of the other solder joints and everything was fine. I just got to the cap and couldn't get continuity through it.

Sounds like that's normal and the cable I made up works in the game so I'm good. :)
 
Thanks guys.

I checked it at all of the other solder joints and everything was fine. I just got to the cap and couldn't get continuity through it.

Sounds like that's normal and the cable I made up works in the game so I'm good. :)
Caps in series will block DC voltages (like your DMM) while passing AC. They show up in a lot of audio circuits that way. If you tie the cap from signal to ground, it will pass the DC and filter out the AC, like in a power supply.
 
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