Double Micro (nano) Ampere meter

[korttoma]

I need this! Please publish instructions ;)

[DavidZH]

Awsome!

I'd like to compare your impressive array of measurement devices against my Agilent U1273A. Actually to decide if I need a µCurrent.... Maybe in an upcoming meetup in NL or BE this summer?

[gohan]

That looks impressive. I'll be waiting for the instructions too 😀

[Nca78]

Wow, that looks nice, I'm stucked with my multimeter and couldn't find the parts avaiable for delivery here to build a µcurrent gold.
Please publish the build instructions !
(Maybe if you could give use the BOM first, then you'll have plenty of time to publish build instruction before we get delivered ;))

[AWI]

@DavidZH Impressive only by numbers ;-) I am prepared to trade my µCurrent for the Agilent :blush:
A meetup sounds good..any specific plans yet?

[AWI]

There it is Micro (nano) ampere meter (double). I need to add a schematic drawing. Any suggestions/ questions are welcome.

[gohan]

Why all those headers are needed?

[korttoma]

Parts ordered :D

[AWI]

@gohan As mentioned in the description: I use it as a "patch panel" to distribute the power and ground to different devices. Wiring tends to get messy on my workbench...

Not mine but similar ;-)

[gohan]

Oh ok, you use it like an integrated breadboard 😀

[sundberg84]

@AWI - did you steal my image on my workbench ;) j/k.
We need to revive the old workbench topic again!

[gohan]

Are resistor needed with a tight tolerance or else?

[AWI]

@gohan No special tolerance resistors needed. The only reason for choosing metal film resistors is that their temperature coefficient is better than carbon types (typical 50ppm/°C compared to 200-500ppm/°C).
As you will be calibrating the circuit you can choose from a large range (0.1 Ohm - 100 Ohm) for the shunt. This will only influence the burden voltage / sensitivity and range (Ohm's laws).

[DavidZH]

@AWI Lemme think about that..... Uuuuuhm. no... 😈

I have no plans for a meetup. Lacking a proper venue for such a thing. Unfortunately.

[NeverDie]

If there is some interest I will try to publish a decent built instruction on Openhardware.io.

I'm interested.

[Nca78]

@NeverDie said in Double Micro (nano) Ampere meter:

I'm interested.

In case you haven't seen it, it's here :
https://forum.mysensors.org/topic/6723/micro-nano-ampere-meter-double/5

[NeverDie]

@Nca78 said in Double Micro (nano) Ampere meter:

@NeverDie said in Double Micro (nano) Ampere meter:

I'm interested.

In case you haven't seen it, it's here :
https://forum.mysensors.org/topic/6723/micro-nano-ampere-meter-double/5

Thanks! It looks a bit complicated to me. I've used one of these breakout boards (https://www.amazon.com/gp/product/B00OPVBEQO/ref=oh_aui_search_detailpage?ie=UTF8&psc=1) as a way to measure 24-bit voltage on capacitors, and it works really well. As you can perhaps tell from the photo:

the chip is fairly simple to use. What I especially liked is that there was already a demo arduino sketch for interfacing with it. That was a real time saver. If I were to build something, I might try that first, if only because it seems like it might be easier (though perhaps, in part, because I'm already comfortable with it). Would using it in conjunction with a sense resistor be all it would take to make an accurate, high resolution current sensor?

[AWI]

@NeverDie that one would work as well. Maybe harder to get and a little more pricy :moneybag:

[AWI]

@NeverDie said in Double Micro (nano) Ampere meter:

It looks a bit complicated to me

btw. Which part looks complicated? It's just a few resistors attached to an ADC board (and sketch ready) I am curious on how you can build something simpler with the ADS1220 (which seems to be a better ADC if you are able to find it somewhere ;-))

[NeverDie]

It sounds like I was mistaken then. In my quick read I thought that I had to implement the entire schematic, not just add a couple of resistors to a pre-made breakout board. I suppose if the schematic were more of a block diagram, that might be clearer for other future readers to quickly grasp, or maybe it's just me.

Why would the ADS1220 be a better ADC? I really haven't looked into doing a comparison. I bought the breakout board that I pictured above from Amazon , but I see that it's out of stock now. I believe the company which made it is in India. I seem to recall that it's open source, so there's always that I suppose. I didn't mind ringing the till for the maker: it was all pre-made, it did what I needed at the time (which was watching in real-time the voltage leakage from supercapacitors that I was testing), it was available with free Amazon Prime delivery, and I wanted something sooner rather than later. So, it fit what I needed at the time. Most of those reasons relate to rapid availability though rather than technical reasons.