Capacitor Tester!

Mohawk said:
The semiconductor tester doesn't identify high current SCR's .... They have specific SCR tester !
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I've got a Leader curve tracer I use for bipolars. I much prefer to look at a scope as opposed to numbers. Max collector voltage is only 100VDC but it has confirmed suspected transistor breakdown voltage a number of times on TO92 types Q1-4 on the 400/700's. I also use it to match transistors where the absolute current gain value is not important.
 
I've got a CEM DT9935 back in Aug (135USD on sale) - and very happy with features / performance - mine came with Kelvin test leads and I bought a set of Kelvin blades crocodile leads, (from other brand but fits nicely on front blades). If you live in the US, is available under a different brand (which I can't remember).
https://www.cem-instruments.com/en/product-id-1147

In US ==> REED 5001
 
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Hi Folks, I have just received my EXTECH EX623. It does not measure ESR, but it has an amazing number of features. AC and DC clamp meter, it has all the features of my Fluke, so the Fluke can stay on the bench. It also has IR thermometer with laser pointer, thermocouples (two included), frequency counter, capacitance measurement, and display illumination. It's not a Fluke but I think it was a pretty good deal for $150 Canadian!
I may eventually look for a dedicated capacitance tester with ESR. Regarding Electrolytics, does the ESR ever become an issue without affecting the capacitance measurement?
 

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Hi Peter
Can you explain further what you mean in this question? Perhaps rephrase?

Regarding Electrolytics, does the ESR ever become an issue without affecting the capacitance measurement?
 
Sure, thanks Joe. I had a feeling I was being a little vague.;
Typically, could an electrolytic cap develop a bad (high) ESR and still read perfectly for capacitance (ufd) ?

Just trying to avoid 'buyers remorse', buying a tester without ESR measurement capability
 
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Peter S said:
Hi Folks, I have just received my EXTECH EX623. It does not measure ESR, but it has an amazing number of features. AC and DC clamp meter, it has all the features of my Fluke, so the Fluke can stay on the bench. It also has IR thermometer with laser pointer, thermocouples (two included), frequency counter, capacitance measurement, and display illumination. It's not a Fluke but I think it was a pretty good deal for $150 Canadian.
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I have a lower model Extech DMM and from the get go, it's slow, auto ranging is unreliable and after two years, the function switch must be fiddled with sometimes to activate the meter.

If/when I purchase another meter, it will not be an Extech. For the time being though, it will have to do.

Maybe yours will be more satisfactory than mine.
 
Hi 62vauxhaul, I'm not too shocked to hear that. I guess there's a reason why the quality was referred to as 'mid range'. I hope to have better luck with mine, very happy so far. It is used and working perfectly at the moment but I don't think it has seen much use. I will not be subjecting it to severe work environments either. I would have gone with a Fluke but for all those features, it would have been close to $1k !
 
62vauxhall said:
I have a lower model Extech DMM and from the get go, it's slow, auto ranging is unreliable and after two years, the function switch must be fiddled with sometimes to activate the meter.

If/when I purchase another meter, it will not be an Extech. For the time being though, it will have to do.

Maybe yours will be more satisfactory than mine.
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I find my two MA445 quite reliable, use them at work for HVAC maintenance, get thrown out on the floor once a day.
Forgotten one in the rain, still works.
Even put 240V in ohm mode, this made a little spark but nothing broken.
But yes the autoranging is not that good and I've never seen the frequency mode working correctly.
Anyway I won't use it for audio measurments.
 
Peter S said:
Sure, thanks Joe. I had a feeling I was being a little vague.;
Typically, could an electrolytic cap develop a bad (high) ESR and still read perfectly for capacitance (ufd) ?

Just trying to avoid 'buyers remorse', buying a tester without ESR measurement capability
Click to expand...
From my late experience - while recapping 2 power supply boards where I found a few bad capacitors (leaking) I decided to replace all the electrolytic caps - about 30. I did compare the unsoldered caps with new ones with 3 parameters from my LCR (besides capcitance value of course). ESR, D (dissipation factor) and Q (quality factor) - not entering on tech details, they are related. I found some caps with cap value still within the 20% tolerance and even ESR not much deviated - but both D and specially Q were very different from the new ones - for me it's a no go for those. Also i cross check ESR with another cheap component tester. Some were not much deviated [ESR /D /Q] from new ones values (specially the smaller uF caps) - so that's a "maybe go" if needed in some future. It's also important at which frequency you do the measures - in most cases for electrolytic should be done @120Hz.
Normally the datasheet of cap manufacturer indicates the reference frequency.
 
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