ESR meter upgrades

[mazenkataya]

Re: ESR meter upgrades

thank u

[momaka]

Re: ESR meter upgrades

The project is always evolving: You have two firmware branches:

M-firmware by Markus (username Madires on the eevblog forum)
K-firmware by Karl-Heinz Kübbeler (username kubi48 on the Mikrocontroller forum)

Thanks!
Bookmarked for when I feel confident enough to upgrade mine some day.
Bricking it would be a major setback for me in terms of being able to check out e-caps.

Both I and STJ have posted a couple precompiled here, but then where is the fun in that?
Much better to go crazy and do it all yourself

Erm.... no. I'll probably completely mess up everything.
Digital circuits was never my specialty. And programing/firmware/compiling... I always screw up somewhere and spend hours trying to do something simple.
So I'll probably just have a look at the links you mentioned and see if there is something pre-compiled there (and hopefully with hand-holding detailed step-by-step instructions for the software-challenged, like myself. )

[stj]

Re: ESR meter upgrades

i do M builds for the TC1 with a rotary encoder and 20MHz if anybody wants it posted.

[Per Hansson]

Re: ESR meter upgrades

Also, I wonder if there's an updated version of the firmware, but for the stock 8 MHz crystal.

The project is always evolving: You have two firmware branches:

M-firmware by Markus (username Madires on the eevblog forum)
K-firmware by Karl-Heinz Kübbeler (username kubi48 on the Mikrocontroller forum)

These can be compiled with any options and crystals you choose.
Both I and STJ have posted a couple precompiled here, but then where is the fun in that?
Much better to go crazy and do it all yourself

[eccerr0r]

Re: ESR meter upgrades

Yes...well equivalent series resistance I'm considering things that you don't see at DC.

Dunno. took an even "bigger" tapped inductor (one side of a transformer) and fed one side into transistortester and it gave me two resistors. Couldn't make heads or tails of it. Actually it's pretty funny what it did, not going to post results to add to suspense

Warning: Don't go too big of an inductor, I think you might damage your transistortester, which would be the sole hint...

[momaka]

Re: ESR meter upgrades

it works a lot better if you use my firmware instead of the factory one.
it's had the esr/inductor code re-written since the chinese compiled it.
also, a 20MHz crystal increases the accuracy.
(but you need to reprogram it to recognise the crystal)

Yeah, I know really should do that, as you've suggested it to me many times now. I don't have a programmer, though... and I generally shy away from anything that has to do with programming firmware, as I never seem to do things right, thus always ending up struggling. (Programming and digital electronics have always been my weak side.)

Also, I wonder if there's an updated version of the firmware, but for the stock 8 MHz crystal.

I thought if I hook up any two wires to the tester, it will give me the expected reading; if I connect all three to the tester, it gives me two resistors...

Hmm. Maybe because the autotransformer windings are a coupled inductor, that's making the TT confused?
In any case, I still think it should be able to measure the inductance of the individual windings, one at a time. If not, then probably the inductance is too low.

ESR of inductors is important too Granted it shouldn't change...

Inductors have ESR?
I thought they only have inductance and resistance from the windings... and maybe a slight hint of stray capacitance when the windings are close to other objects in the circuit??
But I guess at very high frequencies, the skin effect will make it appear as if the windings have overall higher resistance. Perhaps that's what you mean by ESR?

[eccerr0r]

Re: ESR meter upgrades

ESR of inductors is important too Granted it shouldn't change...

[stj]

Re: ESR meter upgrades

i meant capacitors - most people only want the henry's of an inductor

[eccerr0r]

Re: ESR meter upgrades

esr of inductors is supposed to be frequency dependent, but telling inductors from resistors is different...

[stj]

Re: ESR meter upgrades

the esr is more accurate

[eccerr0r]

Re: ESR meter upgrades

i dont have one.
what the newer firmware does is take several averaged readings at different frequencies to get a better result.

If it's just that... it's still wrong

[stj]

Re: ESR meter upgrades

i dont have one.
what the newer firmware does is take several averaged readings at different frequencies to get a better result.

[eccerr0r]

Re: ESR meter upgrades

So what does your firmware report when you have an autotransformer attached?

Two inductors in series doesn't quite work for an autotransformer...

[stj]

Re: ESR meter upgrades

it works a lot better if you use my firmware instead of the factory one.
it's had the esr/inductor code re-written since the chinese compiled it.
also, a 20MHz crystal increases the accuracy.
(but you need to reprogram it to recognise the crystal)

[eccerr0r]

Re: ESR meter upgrades

Probably the inductance is too low to test??

I thought if I hook up any two wires to the tester, it will give me the expected reading; if I connect all three to the tester, it gives me two resistors...

[momaka]

Re: ESR meter upgrades

Just wondering... Ever since I got this AVRTransistorTester it's pretty much stayed in my "toy" pile and have yet to actually find a bad transistor or other device that I already knew of its status of good or bad from other tools or debugging techniques... Has anyone felt the same way?
...
Yes this sorta sounds like parade raining but just wonder how other people feel... do they use it a lot? Has it saved you effort? How so?

I use mine almost exclusively as an ESR meter / electrolytic cap tester (for testing caps out of circuit.) I know it probably sounds silly to pull caps out just to test them. At that point, many people will probably opt to just replace the cap(s) in question. But that's not always possible when testing the primary caps in a SMPS, which tend to be expensive. I do like to test them, though, because if bad, and if the PSU has APFC, chances are things will get destroyed on the primary at some point. On the other hand, if the cap(s) is good, I put it back in.

I also use my GM328 once in a while for measuring inductance on mostly larger inductors / non-SMPS transformers.

I rarely use if for anything else, though.

BTW seems that having big caps inserted on power up really slows down the power on auto self-cal it seems haha.

Yeah, I've noticed that too.
Not only that, but sometimes my GM328 will complain it hasn't been calibrated if I insert a relatively large cap (typically 4700 uF and up)... though not always. Drives me nuts when it does that, especially if it does it a few times in a row. It still works if I don't calibrate it, but the constant nagging message is annoying, so I end up calibrating it right away... until it does it again. I do wonder if the MCU memory is going bad, though. It never used to complain about the calibration probably for the first 3-4 years after I bought it and calibrated it (if not more.) Actually, it really only started doing it very often this past year.

Fail. Autotransformers show up as two resistors...

Probably the inductance is too low to test??
I know at least my GM328 can't go lower than about 20 uH, IIRC. And sometimes even slightly higher than that will still report as a short-circuit / low value resistor, but no inductance (case in point: most output inductors on PSUs.) VRM inductors from motherboards are completely out of the question here, with most nowadays being under 1 uH. I actually performed a curious test: I gathered several such VRM inductors from scrap Xbox 360 motherboards and wired them in series. I don't know what their inductance is, but based on the circuit design's age, I'd guesstimate 2.2 uH or less. Wiring 4 of them in series did not give any inductance. I think even 6 of them didn't. And at 8x series, it reported 0.1 mH (10 uH) only half the time.

So yeah, at least the GM328 is not very useful for testing low-value inductors.

[eccerr0r]

Re: ESR meter upgrades

It didn't for me... said two resistors, but that's besides the prob..l..em...
hmm. I think I figured out why it reported two resistors. aaah... circuit design.

[stj]

Re: ESR meter upgrades

shouldnt it show as an inductor?

[eccerr0r]

Re: ESR meter upgrades

hmm... thinking about it, trying to test an autotransformer (tapped transformer) might not be a great idea... but depends on how well the circuit is designed....

[stj]

Re: ESR meter upgrades

if you have the newer firmware for the opto-test it gives you the transfer value