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ESR TEST EQUIPMENT

HellasTechn

Apr 14, 2013
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Good day people !!!

Today i was working on a digital tv signal receiver that had a bad capacitor (inflated like a baloon).

So i did a little search for a device that measures capacitors (Capacitor meter) and i came across the ESR meters that are better because they also measure the resistance of the cap.

Could you suggest me a cheap ESR meter ?

I found this on Ebay but does it worth the monay ?

http://www.ebay.com/itm/All-in-1-Co...108?pt=LH_DefaultDomain_0&hash=item1c405fe6c4

THANK YOU
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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That's probably not bad for an ESR meter.

Absolute accuracy is not as important as being able to take comparative measurements (from my experience).

You're never certain what the ESR of a failing cap might have been when it was new, but you can compare it to a new one. If the suspect one is significantly higher (more than two or three times) then you could consider replacement.

Some meters have a table of acceptable values for various voltage and capacitances. Copying down one of these would be a good thing.

If you get one of these, see if it works on resistors. Does a 1 ohm resistor show as 0 uF 1 ohm? If it does then you can get a 1, 0.1, and maybe 0.01 ohm resistor to determine if your meter is within 10% or so -- and that would be fine. You will find that odd things happen at very low ESRs, so anything below about 0.05 ohms is going to depend probably more on the connection you've made than to the ESR of the cap.
 

HellasTechn

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That's probably not bad for an ESR meter..

Are you talking about the one i found on Ebay ?

Oh and by the way. Does anyone have an updated (2014?) capacitor's ESR table ?

I Googled it and found a few outdated esr tables. THANKS
 
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HellasTechn

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Anyone has an ESR table for capacitors i coulp use as reference point ? Thanks.
 

(*steve*)

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I just googled "ESR table" and got a heap of image results.

I generally accept what is on the front of my Bob Parker ESR Meter Mk:II, but in practice I tend to compare the ESR with a known good replacement.

If a cap is *really* bad you tend to see order of magnitude (or greater) changes.

If you can find datasheets you may be able to find specified values for the ESR, but in practice you often can't ID the cap that well. With luck you won't see too many 2014 caps failing for a few years yet :D
 

dude

Apr 15, 2014
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Like steve said, if a cap is bad and is effecting the operation of the circuit it will be way off the chart. It's best not to get to picky, once you have found the faulty cap it will be obvious. I am saying this from the point of making money from repairs, you have to be fast in your turn out otherwise your pile of incoming stuff will get bigger and bigger and your income smaller and smaller :D Capacitors that cause problems are usually the ones located right next to heat sinks and of small value, the bigger the cap, the less likely it is to fail. An ESR meter will not always pick out a faulty cap, so don't put all your faith in it. Here's a pic of mine, the chart on that is really all you need and after a while of using it you won't even need it, you'll be able to just judge it yourself.
 

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HellasTechn

Apr 14, 2013
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Yes i understand all you say steve and dude. I have come across lots of failing capacitors of different value (from 10uf to 2200uf) but i think that comparing the suspicious one with a known good one is the best. then i could just build my own esr table or just know by experience.

The esr i bought is a cheap cineese one. Does not have esr table. Some of them indicate OK or BAD but not this one.
http://www.ebay.com/itm/281235252022?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
 

HellasTechn

Apr 14, 2013
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I got the tester yesterday and it is really very good !

I have a question though. When i test capacitors it provides me with the following information for the capacitor:

1.Capacitance value.
2.ESR value.
3Vloss.

What is Vloss ? it is displayed in %.

THANKYOU
 

(*steve*)

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Almost certainly it has something to do with dielectric loss. But I'm also pretty sure that is frequency related (as is ESR), so expressing it as a percentage is odd.
 
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