Yet Another Parasitic Draw Case

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hexibot43
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Re: Yet Another Parasitic Draw Case

Post by hexibot43 »

Alright. I'm giving up on the Raspberry Pi for now. Sounded like a great idea. The footprint on my bench is small. But I just can't get the PicoScope 4423 I have working with it. Usb permissions?!? My Imac will be running the show for now. Honestly, I just plugged my scope into my Imac and everything just works. A little bit to learn still but it is logging data like a champ.

To be continued as the data accumulates in my Imac.

Running Picolog 6 to record data. What would be the easiest way to add temperature data to my logs? We've just started getting colder here, and it seems to be effecting my recordings.
Last edited by hexibot43 on Sat Aug 08, 2020 10:35 pm, edited 1 time in total.

Steve Smith
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Re: Yet Another Parasitic Draw Case

Post by Steve Smith »

Hello and thank you for the feedback

The Raspberry Pi adventure looks to be a disappointment at this stage and I want this to work for you.

I must apologize as i mentioned in my previous post I would liaise with colleagues and this completely slipped my mind. I will try for you ASAP, did you try the support line?

Regarding temperature monitoring, a thermocouple sounds like the solution but we are going to need an interface which will require a battery and here lies the problem as we want to get around the dependence upon batteries .

I guess the good news is the demand of a thermocouple on a temperature transducer battery is minimal and will suffice through your battery monitoring.

I will take a look at Pico T & M options and feedback

Take care......Steve

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Re: Yet Another Parasitic Draw Case

Post by Steve Smith »

Hello again, sorry no joy on a thermocouple adapter/interface for your scope (4223)

This has now been resolved thanks to the introduction of the 4x25A scopes, however, this does not help us here!

No doubt a quick Google search will find you a battery powered temperature interface/transducer (e.g. 1 mV/Degree C/F) in which we can connect a thermocouple and then convert the 4 mm outputs to BNC.

It sounds like a bit of a mission but it will allow you to then log temperature alongside battery voltage

I hope this helps, take care......Steve

Martyn
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Re: Yet Another Parasitic Draw Case

Post by Martyn »

For the installation on the Raspberry Pi can you try

Code: Select all

sudo apt-get purge wget
sudo apt-get install wget
wget -O - https://labs.picotech.com/debian/dists/picoscope/Release.gpg.key | sudo apt-key add -
and if it still hangs cut and paste the console output so we can take a look.
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Re: Yet Another Parasitic Draw Case

Post by Martyn »

Further to this to check versions type these three commands
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hexibot43
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Re: Yet Another Parasitic Draw Case

Post by hexibot43 »

I really want to thank you all for helping me. I am a dog with a bone. Not giving up. In the picotech forum for picolog, I got some help too.

I have my Raspberry Pi 3b+ up and running well with Picolog6 beta. I set it up as I had it set up with the Imac. Saved where I left off on the Imac. And copied the file to the picolog folder on PI. I really loved how Picolog had no problem when I paused the recording on Imac, to take some time with scope on the Pi. And then when I plugged it back in. Just un-pause it And continued logging as if nothing has changed. The Annotation (notes) feature is great too. I enjoy using picoscope6 software, but I'm really loving this picolog.

So much of the time I want to use the scope so that I don't have to sit there hoping to get a glimpse of the problem. I just want to hit record and walk away. For example, last week I had a car that would just suddenly die. And of course, I tired of waiting for it to die. Walked away. Came back to a dead car. And when I go to start it back up, it just starts. No answer because I didn't sit there waiting. Perfect place to use the picolog. When I come back to the dead car I can just rewind and look at the data. Even if it took hours to catch it. looking forward to trying my hand at that. Usually working on three cars at the same time. That is the kind of tool that can really help out.

Thanks Again Everyone,

Mab

Don't always need crazy hi resolution data. Just a slow methodical look at the problem.



I

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hexibot43
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Re: Yet Another Parasitic Draw Case

Post by hexibot43 »

So where was the issue with connecting the scope to the Pi. A file needed to be embedded in the software for the usb connection of the Scope. It was missing. And once I was able to write that file into the rules directory everything was right as rain.

From the command line
"lsusb " gave me a glimpse of all USB devices connected to the Pi. And you could see my scope show up when plugged in.

But no connection between Picolog and Scope. There was not a rule to the interface to allow the 2 to communicate. A rule was missing stopping this communication. Once in place the communication simple happens.

https://www.picotech.com/support/topic40687.html


Seems so simple now that it works. But I alone did not have the skills to figure it out.

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hexibot43
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Re: Yet Another Parasitic Draw Case

Post by hexibot43 »

Steve Smith wrote:
Tue Aug 04, 2020 11:59 am
Hello again, sorry no joy on a thermocouple adapter/interface for your scope (4223)

This has now been resolved thanks to the introduction of the 4x25A scopes, however, this does not help us here!

No doubt a quick Google search will find you a battery powered temperature interface/transducer (e.g. 1 mV/Degree C/F) in which we can connect a thermocouple and then convert the 4 mm outputs to BNC.

It sounds like a bit of a mission but it will allow you to then log temperature alongside battery voltage

I hope this helps, take care......Steve
Hopefully this is very simple solution to Temperature input. Found an Analog Devices, tmp35,36, 37 device would give me a simple voltage output that I could read in on one of the 3 channels I still have left on the Pico 4423. Do some simple math to it, and be able to log it with my other data. Ordered a couple and should see it by Wednesday. I should not have to worry about issues of power isolation. I am thinking of just using an(is that right?) USB cable cut open to power the circuit. Or run it off the rail of the Pi. There will be no physical contact to any anything other than the case of the battery. Hmmm. No need to even touch the case. Just a reading of Ambient Temperature. No special units to use.
Am I mistaken? Maybe if I only had a two channel scope that might no be a smart way to go. But I'll still have two left over channels for now.

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