Finally built the Bob Parker "Blue" ESR Meter

[stj]

Re: Finally built the Bob Parker "Blue" ESR Meter

Those look pretty neat especially for the price. Do you use this seller specifically?

i do because they are consistant
they have silicone ones too.

[megaraider]

Re: Finally built the Bob Parker "Blue" ESR Meter

huge probes!
i have several of these - i get a pair for every meter!
https://www.aliexpress.com/item/32848907433.html

Those look pretty neat especially for the price. Do you use this seller specifically?

Not a ton of options when you need modular ones that will accept 4mm banana plugs.

Agree with @stj.
Plus those banana plugs are completely useless. Cut the probe wires if needed, and replace.

[jayjr1105]

Re: Finally built the Bob Parker "Blue" ESR Meter

I'm still tossing the idea around in my head to convert it to banana jacks like the MESR-100 meter. They give you an extra top plate, just need to find jacks like these somewhere.

[stj]

Re: Finally built the Bob Parker "Blue" ESR Meter

you would be better using the shielded type like on multimeters.
you can still use 4mm banana jacks, but you can also then use comercial probes and cables.

[eccerr0r]

Re: Finally built the Bob Parker "Blue" ESR Meter

Incidentally, where does one get shrouded banana jacks?

--

Ah, looks like ponoma makes some and distributed by the usual newark, mouser, digikey, etc...

Sigh. Wonder if I should convert my old DMMs to shrouded type jacks so I can use my probes from dead DMMs...

[stj]

Re: Finally built the Bob Parker "Blue" ESR Meter

they are everywhere - you need to look for "test connectors" or similar descriptions.
https://www.rapidonline.com/4mm-single-pole-connectors

[eccerr0r]

Re: Finally built the Bob Parker "Blue" ESR Meter

Question if it's easier to replace the old DMMs' connectors, or is it time to get the probes circumcised...

[stj]

Re: Finally built the Bob Parker "Blue" ESR Meter

that depends on the meter.
i have drilled out the molded crap on a couple and fitted ones with locking rings, but it depends on clearance.

[megaraider]

Re: Finally built the Bob Parker "Blue" ESR Meter

Question if it's easier to replace the old DMMs' connectors, or is it time to get the probes circumcised...

Well the answer is quite obvious:

1. Once circumcised... you are stuck (in fact, not you but the probes... )
2. Change the sockets and you're free to swap probes (see @stj remark about clearance)
   Even free to attach alligator clips when handy

[volkswagenvan]

Re: Finally built the Bob Parker "Blue" ESR Meter

I built the Bob Parker Blue ESR meter kit a few years back and i still love it today.
All except the graph on the face,... I had to make a chart to replace it with!

[redwire]

Re: Finally built the Bob Parker "Blue" ESR Meter

What ESR chart did you go with?

I've heard measuring battery ESR can also be done if you add a series DC blocking capacitor. Good for many testing different batteries, LiIon and car batteries with the Blue ESR meter.

[volkswagenvan]

Re: Finally built the Bob Parker "Blue" ESR Meter

I kinda made one from the old Bob Parker meter.

[volkswagenvan]

Re: Finally built the Bob Parker "Blue" ESR Meter

Printed it to sticker paper and after applied I put clear laminate over it!
I made a bunch in case i messed up. lol
Worked fine on the first one.

[jayjr1105]

Re: Finally built the Bob Parker "Blue" ESR Meter

Did the included sticker give you trouble removing it? I agree it's a bit too vague. Need a simple chart. Plus I put mine on a little too high so you can't quite see the decimal positions if it's slanted too much.

[volkswagenvan]

Re: Finally built the Bob Parker "Blue" ESR Meter

I can`t recall but i bet there was some hot air involved.

[volkswagenvan]

Re: Finally built the Bob Parker "Blue" ESR Meter

Hey redwire
You can measure battery ESR with the Blue as is. No need to add anything.
This is only if you did not do any diode mod to your meter!
(back to back diodes on the input)

[redwire]

Re: Finally built the Bob Parker "Blue" ESR Meter

Hey I looked at the schematic and it's already got a 22uF BP cap to block DC and not damage the ESR meter
It must be other shitty ESR meters I've built like the 5-transistor special that need a cap.

Tried a bad 12V 7Ah gel-cell and its ESR 2.3 ohms, a good one is 0.1-0.2 ohms.

[volkswagenvan]

Re: Finally built the Bob Parker "Blue" ESR Meter

Cool,... You got a new toy!

[stj]

Re: Finally built the Bob Parker "Blue" ESR Meter

doesnt esr on batteries vary with charge?

i know on 18650's i salvage that they look a lot better after a full cycle

[jayjr1105]

Re: Finally built the Bob Parker "Blue" ESR Meter

Did a few more minor upgrades. New thicker and longer cables, better banana plugs, cut off the massive finger guards on the probes, and 3d printed a case that holds the meter upright.