Yet another ESR meter!

[gonzo0815]

Re: Yet another ESR meter!

It`s simple, cells with high ESR are bad, as their voltage will break under heavy load. Here i can buy a special battery checker, which does basically the same like an ESR tester, but it does include high current discharge readings.

[kc8adu]

Re: Yet another ESR meter!

i simply test a cell like a cap.
a good one .01-.03
bad ones are usually really bad .several ohms.
use a new cell as a reference.

[willawake]

Re: Yet another ESR meter!

thanks guys

[PCBONEZ]

Re: Yet another ESR meter!

Yes thanks.

I think maybe I'll add a second set of test lead jacks for that.
One set diode protected for caps and the other not for batts.
[Easier than jerking with diodes in leads and I don't have to keep track of 'special' leads.]

I joined this site just to learn how to fix mobo's.

~~ Now I'm a meter modder... whoo hoo!!

.

[Per Hansson]

Re: Yet another ESR meter!

Nice, please post PIC's of your modded meters for us all to drool over

[willawake]

Re: Yet another ESR meter!



got my blue esr kit last week. looks great. the case is very good, nice pcb and no skimping on the components, caps are nichicon and panasonic. full report soon.

[zandrax]

Re: Yet another ESR meter!

Willa, didn't you review another esr meter?
Anyway I'm waiting for.

Zandrax

[willawake]

Re: Yet another ESR meter!

yes but i did not build that one

[zandrax]

Re: Yet another ESR meter!

Now I understand

Zandrax

[starfury1]

Re: Yet another ESR meter!

Willa did a review on the EVB pre build version with lots and lots of nice big photos
the EVB is Bobs design with a reworked PCB from memory
(dont think there was any components changes or very few)

Thats the latest kit for Bobs design
(not sure on the changes there thought)

Yeah willa post, lots of big photos so I can turn Blue with envy

Cheers

[willawake]

Re: Yet another ESR meter!

well i managed to lift a pad which i dont understand cos i was doing so careful soldering. it still looked connected but i fail the before installation of chips test.


early photo just to indicate where the lifted pad is

With IC2 and IC3 still not installed connect the supply leads to the batteries (or a 9V DC power supply), with a milliammeter in series with one of the supply leads.

Initially, you should not see any current being drawn. Press and hold the pushbutton switch and check that the current drawn is between 3 and 5 milliamps (the current will initially pop higher as all of the capacitors charge). If it is significantly higher or lower, start looking for assembly errors (component placement errors, missed solder joints and solder splashes).

well i think this means i should have one lead on the battery + and one lead on the connection of the battery + supply lead. i get 0 and when button pushed i get briefly 0.01 milliamp

gonna do some checking tomorrow

[i4004]

Re: Yet another ESR meter!

what was the iron temp?

[willawake]

Re: Yet another ESR meter!



iron temp was 350oC

[starfury1]

Re: Yet another ESR meter!

DC Current measurement
meter alway becomes part of the circuit

so yes in series
(you effectively must brake open the circuit)

As in
multimeter on current range, positive lead to most positive point
This case, battery positive terminal
negative lead to more negative point (this case) PCB positive point
(battery connection)

So yes willa correct connection, just expended a bit on it for others

This test should be done at the second photo stage above...
before you put IC's in circuit
(but everything thing in place else if memory serves me)

I know you know what your doing with a soldering iron willa
so possibly a fault with pcb
or maybe diode was high and you put a bit of force on PCB without realizing it.

Amway I am a lot less incline to blame your skills or equipment
more so just plain bad luck

Yellow things a crystal ..interesting

Let us know what happen with the test please

(its very easy to miss read a resistor esp one on blue 1% 2%,
transistor too, easy to mix up npn and pnp in same package)
I made a boo boo or two with mine in construction

looking good willawake

[willawake]

Re: Yet another ESR meter!

DC Current measurement
meter alway becomes part of the circuit

so yes in series
(you effectively must brake open the circuit)

uuuh.....it checks out now

[i4004]

Re: Yet another ESR meter!

uh willa, but you broke the circuit open if you did it according to your description too:

"well i think this means i should have one lead on the battery + and one lead on the connection of the battery + supply lead."

this should mean you broke the circuit, right?
hehe...as otherwise it would be one weird current measurement of putting 2 probes on same spot.

to reiterate once again: to measure current, you break open the circuit and connect meter probes to 2 contacts that you've opened up this way.

[starfury1]

Re: Yet another ESR meter!

Thanks Willa ...
(another great mis typo by me that should be)
"meter always becomes"

basically the meter becomes the supply cable (battery lead)
(or part of it)
....in this case

So great it works as should be so far

looking good willawake ...looking good

Cheers

[Krankshaft]

Re: Yet another ESR meter!

We've all lifted traces at one time or another.

I don't even use a temperature controlled iron I use a 20 watt Hakko Dash and it works for my purposes.

I posted a few pics of this meter here with a little building commentary:

https://www.badcaps.net/forum/showthread.php?t=4822

I hope you have a fully variable power supply for setting the low battery indicator. Otherwise you will need to build the little discrete voltage regulator in the manual.

[severach]

Re: Yet another ESR meter!

I adjusted the voltage dropout with an el-cheap variable wall wart, no expensive power supply needed. I set it to 3v, attached the 9v lead to the ESR meter, and placed the 82 ohm across as a load. 5.45v was close enough for me. Adjust fast since the 82 ohm resistor heats up quick. Don't try that with the 5.6 ohm resistor unless you have one that can dissipate the max wattage of your transformer up to 5 watts.

I used a 30W Weller Therma boost and tin/lead solder to minimize the likelihood of burning traces. No RoHS for me.

I left my transistors with as long as leads as would fit in the case so I could keep the heat away with a reverse tweezer. I didn't think of this when soldering in the diodes.

I soldered the test resistors right into the ESR meter. One side is soldered to one test lead and the other is wrapped around the case. I can calibrate my meter any time and the resistors never get lost. You can see their little wires poking out just to the right of the 7 segment displays.

>its very easy to miss read a resistor esp one on blue

I measured all mine. No mistakes by me or the resistor factory.

>easy to mix up npn and pnp in same package

I placed all of each type at once to prevent mixups.

Here's the easy way to hook your amp meter up for the test. Polarity doesn't matter with a digital meter. I get 9ma operating and 0ma off.

[willawake]

Re: Yet another ESR meter!



i wanna build the variable power circuit but i could not get a 3904 tranny. Of course the shop only had 3903 or 3905..... are these any good?

if anyone is wondering why its taking so long to build the thing. i found out i was missing IC3. I got two pieces IC2 instead. Anatek dont mess around, i received the part via express mail EMS