Looking for some parts selections as follows.
- A raspberry pi that can accept up to 3 analogue inputs and 2 digital inputs and a USB programming interface.
- A 4g + GPS Interface with suitable antenna.
The power supply available to source the pi/ system is 12Vdc. (not sure what voltages are required for the pi and 4G/GPS?
May need a voltage boost module/s?
I have located 4-20mA to 0-2.5/3.3/5/10/15v converters for the Analogue inputs I assume that the I/O Accepts any of these voltages?
Can you assist with some suitable selections.
Welcome to the forum!!
Just to confirm, did you want a full Raspberry Pi with an OS or would a microcontroller work for your project?
If its a single board computer (SBC) you are after I’d check out the following:
Would it be possible to send through some links for these products? The Pi exclusively has digital IO and no ADC onboard so an external dedicated chip is required.
Let us know if you have any questions about anything!
Thanks, and please find attached.
Essentially, we just need to be able to pump a couple of tank levels to a cloud-based server using 4G MQTT + with addition of ability to track the units location via GPS.
Hope that this assists.
4-20in voltage out converter.pdf (400 KB)
Pi application sketch.pdf (103 KB)
Just checking that you received my response with attachments yesterday.
It looks like the products I linked above should work well in the block diagram you provided!
The 4G HAT has onboard GNSS for location as well.
From ADC Pi at Raspberry Pi GPIO Pinout, and the pin usage on the 4G HAT page, there wont be any pin conflicts.
Let us know if you have any other questions!
Is the 12v voltage level ok to supply all of the kit or will we need a booster? (Believe the SHIM kit covers this off).
Also! is there a recommended dual antenna for the 4G HAT.
Reckon this will close things off…
The SHIM should happily power the Pi, since the 4G HAT is attached via the headers it will draw power through that, there might not be too much headroom with the 2A regulator onboard so a second might be necessary for the 4G HAT, you’ll have to ensure the 5V connection is not contunuous between the two.
The 4G HAT actually includes all of the necessary antennas, check out the bottom of the product page for the package contents.
One last check in with you around the Analogue inputs. We would understand that the ADC Pi will be required to interface between the 4-20mA converters (as per what I had attached) and the Pi itself. The converters can be set to output a 0-5v from the 4-20 in, but assume that the ADC Pi in this case will provide the safe (tested) galvanic Isolation for the Pi.
Would you be able to provide us with data on the Raspberry Pi that you would recommend, noticed that you hadn’t sent any details through. In addition, could you confirm the last email points around the ADC Pi and if it is required as the 4-20mA converters can create a 0-5v signal?
Something else has arisen and it seems that we will also need to input a voltage of between 0-15Vdc (Max) is there an interface to allow this to be input into the Pi?
Apologies as this has become a little protracted and should be the final queries before wrapping up.
I can see now that the ADC pi is required as it is the voltage to digital conversion, Essentially we can set the 4-20 converters to produce a 0-5v output to input into the ADC Pi.
Just need info on suitable Pi and whether you are aware of a 0-15v ADC.
Very sorry for the delay!!
Unfortunately the ADC Pi doesnt offer much in the way of protection for the inputs, typically most makers will be using this in an environment where reliability isn’t a major concern.
Which kind of data were you after about the Raspberry Pi’s? There are some extensive documents regarding the hardware, and software on their site, Raspberry Pi Documentation
You’ll likely want a wider range ADC module such as this ±24V breakout: Pimoroni ADS1015 +/-24V ADC breakout | Core Electronics Australia
No worries at all! Projects generally tend to blow out a bit at the end
You can choose SIM7000. It is a 4G module. Compatible with Raspberry PI.
Hey Thanks Liam.
I Managed to locate the info that I needed.
Thanks for this information.