Peak ESR Meter wrong values HELP

[Shodan486]

Hi

Link

This one is a big shit... I've bought this quite spectacular ESR meter, really didn't bother about the quality cause I trust english products, but maybe I am mistaken - It just simply shows strange values or doesn't even bother to detect some. Example: I am measuring a IN-CIRCUIT 16v 1000uF cap, and I get ESR 0.41 ohms and C is 6050uF ?!?!? Now what the hell? another story - I get a In Circuit / Leaky message, which means it can't measure the capacitance (still can't see the reason) or the cap is leaking...wel,l I don't think it's true when I KNOW the board is good and runs...I tested this item I am having in my hands for only few hours on quite a number of mobos and it acts the same... I only measured a 100uF cap with quite precise results (106.82uF) but the ESR was only 0.41 ohms...The very problem is the capacitance - Am I missing something or let's face it - It's broken.

BUT! It quite correctly works on OUT-OF-CIRCUIT state. I have bunch of rubycons 3300uf and 1800uf and those show their nominal state, some of them actually +/- 200uf, which I assume is still OK. Just any experiences would help, tomorrow I'll contact the seller and ask him the same thing here.

[stj]

Re: Peak ESR Meter wrong values HELP

you cant meter esr in circuit usually because there are other things in the circuit that mess with the readings.
specially with motherboards & psu's

for example, your 1000uf cap - was there 6 of them in the same area?
they are probably all connected together!

[seanc]

Re: Peak ESR Meter wrong values HELP

What STJ says.

You've accurately described mine, it works fine thank you very much.

[Shodan486]

Re: Peak ESR Meter wrong values HELP

that's quite a good idea, it seems, that you're right, I can easily measure a row of 4 caps of the same type, BUT - How come I cannost measure just a random 1500uF cap for, let's say a DIMM subsystem? That's just an example, VRMs can be measured, the little tiny ones are almost totally accurate, but unable to measure just a random cap for the AGP, that's another example...Share your knowledge anybody please, me desperate

[stj]

Re: Peak ESR Meter wrong values HELP

because your metering more than the cap, your also metering the chips!!
and probably some ceramic caps too.

[Shodan486]

Re: Peak ESR Meter wrong values HELP

So I keep measuring various stuff and something bothers me: Is it possible to always get 0.40 -0.45 ohms on ALL caps I've tested, doesn't matter if they're in or out the mobo, doesn't matter it's Rubycon or Jackcon, I always get numbers ONLY within this gap?...Now what the heck?

[370forlife]

Re: Peak ESR Meter wrong values HELP

Measure out of circuit.

[Shodan486]

Re: Peak ESR Meter wrong values HELP

As I said - no difference...a brand new Rubycon out of mobo shows the same value as a stupid Jackcon soldered on a mobo...

[seanc]

Re: Peak ESR Meter wrong values HELP

What does the Jackon show off of the mobo? Is it bulging?

[Shodan486]

Re: Peak ESR Meter wrong values HELP

Both are in a good shape, can't tell the age, but as for those rubies, I bought them about 3 months ago, but again, I can't possibly know when they were manufactured. The Jackasscon board is a Athlon XP (can't remember because I was even tryin' to use his one to get some other data, it was his board), but it matters not because it is quite impossible to get such very close readings, not to mention numerous identical ones, on many boards from variojus vendors (I got plenty, trust me)...I really don't quite know, but I have discovered a calleague who too is in possession of a ESR meter, so we're gonna compare. Still feel free to add anything...

[stj]

Re: Peak ESR Meter wrong values HELP

are they the same voltage & uf?

[Shodan486]

Re: Peak ESR Meter wrong values HELP

nope....Rubycon Ultra Low ESR 3300uF 6.3v and Jackcon 3300uF 10v

[Toasty]

Re: Peak ESR Meter wrong values HELP

Try measuring a resistor. Try a 10Ω and a 0.1Ω. Do they read correctly (or close)?

Did you do the "Probe Compensation" step? Page 10 of User Manual.

[barry wilkins]

Re: Peak ESR Meter wrong values HELP

Very strange ?
Glad I designed and built my own ESR meter .
One of the problems is with the applied ac waveform ,it has to be kept low around 100mV to stop the circuit reading anything else in the circuit

Barry Wilkins

[Toasty]

Re: Peak ESR Meter wrong values HELP

Shodan486 - Was this ever resolved?

[Shodan486]

Re: Peak ESR Meter wrong values HELP

because your metering more than the cap, your also metering the chips!!
and probably some ceramic caps too.

I know this is a bit old, just browsing history ...but what did you mean by ''chips'' ?

[Per Hansson]

Re: Peak ESR Meter wrong values HELP

He means anything else in the same circuit as the capacitor
When you measure in circuit you measure not only the capacitors, but resistors and ceramic capacitors in the same circuit aswell

[PCBONEZ]

Re: Peak ESR Meter wrong values HELP

I know the ads say these meters can check caps 'in circuit' but that only works if there are no resistors, diodes or other caps in parallel.

ESR meter works the same as a regular ohm meter but instead of a DC test signal it uses a small sine or square wave at approx 100kHz.
The voltage is too small 'to turn' on any IC chips and they's where they come off saying it's okay to use in circuit.

As toasty said you can use a resistor to check an ESR meter because resistance is the same be it DC or 100kHz.

Not a bad idea to keep a few values of +/-1% tolerance resistors around to spot check the ESR meter [and your ohm meter too.]

.

[Shodan486]

Re: Peak ESR Meter wrong values HELP

I know the ads say these meters can check caps 'in circuit' but that only works if there are no resistors, diodes or other caps in parallel.

ESR meter works the same as a regular ohm meter but instead of a DC test signal it uses a small sine or square wave at approx 100kHz.
The voltage is too small 'to turn' on any IC chips and they's where they come off saying it's okay to use in circuit.

As toasty said you can use a resistor to check an ESR meter because resistance is the same be it DC or 100kHz.

Not a bad idea to keep a few values of +/-1% tolerance resistors around to spot check the ESR meter [and your ohm meter too.]

.

Thanks BONEZ, you even answered my repetitive question of damaging something on the board when using the meter inappropriately. And one more annoying question : I happened to obtain another of these PEAK stuff and this one acts weird - it is waiting for me to put the probes on the desired target...so when I put them on the spots, it measures the cap correctly...but sometimes nothing happens, it's waiting for the ''measured component'' while probes on it. This definitely points to a meter malfunction of some sort, I'm not questioning that (probe compensation done numerous times), I'm questioning if this kind of malfunction of the meter can damage the measured PCB motherboard? Because when I saw it first time, I said to myself ''Nah, that can't be, let's try it again'' - can this ''let's try it again'' kill something?

Anyways, what's gonna happen when I try measure the CMOS battery itself? Still socketed on the mobo?

[PCBONEZ]

Re: Peak ESR Meter wrong values HELP

It think maybe the no reading is oxidation on probe tips or on the device leads or solder pad.

No, trying again won't hurt anything.

Use a DC volt meter to check the CMOS battery.

CMOS batteries aren't rechargeable except on some really old stuff and occasionally in laptops.
.