Help! Load Cell with Leobodnar board

[Bitacaia]

Hi,
I have recently made a DIY Hydraulic Handbrake, but unfortunately it stop working (need to make an autopsy). So i decided to attach a load cell (the same used in the Fanatec CSP V1) to the Handbrake using the Leobodnar board "BU0836-LC".

Example of the loadcell:
https://www.aliexpress.com/item/FRE...lgo_pvid=4ec473f6-c5ee-4aca-8e33-a879bd92ad54

But unfortunately I cannot have any reaction in Windows when I connect the board. I tried to connect in the normal analog ports, no result... I tried to connect to the Loadcell amplifer port, no result...
NOTE: the board is working, just the analog axis doesn't move, although it detects something connected.
To check if the loadcells are working, I attach them to the my pedals, and they work...
I even played with the wires position, inverting in all combination possible, with no result...
I have no idea what can i do next...

So, the question:
With this specific Loadcell, is mandatory to have a Amplifier? Or, i can connect directly to the analog ports?
So, please help me with this problem!!!

Tiago Viana

 

[winet]

Your Fanatec load cell is not compatible with the Bodnar board . You would need to use a standard load cell with 4 wires.

 

[Bitacaia]

So, update about the problem.

I will use basic language because i don't understand much about electronics.

The problem is: The load cell from Fanatec or "toilet scale" only uses 3 wires. But the load cell amplifier requires a 4 wires connection. (called Half Bridge)
So, is require to connect something between to transform it 3 to 4. Leo Bodnar offers a PCB with this function. But it will cost me 20€ to have it at my door.

I found on the internet some alternatives to the LB board.
One requires a setup with 2 LC (already tried and it works, but i need to have a extra LC hanging around, doing nothing).
The other, some how, i connect 2 1k Ohm resistor. Unfortunately i could find a good tutorial with this setup. I found 2 setups, but it didn't work.

I will keep posting my challenges!

Tiago Viana

 

[3ller]

i think you can use the load cells stacked in parallel and you will have 2 times the capacity so a 100 kg load cell, give it a try.

 

[Bitacaia]

Hi!
So, good news. I solve all the problems. In one forum i read that i needed to use 1k ohm resistor, but didn't work.
So, luckily i had some 10k ohm resistor around, and it worked. So, no need to have two LC connected. I will make a schematic of this, for people with interest on this subject.

Note: my knowledge of electronics, don't allow me to explain why 1k isn't good and 10k is... so, don't expect me to answer any complex question...

 

[fux]

Hi!
So, good news. I solve all the problems. In one forum i read that i needed to use 1k ohm resistor, but didn't work.
So, luckily i had some 10k ohm resistor around, and it worked. So, no need to have two LC connected. I will make a schematic of this, for people with interest on this subject.

Note: my knowledge of electronics, don't allow me to explain why 1k isn't good and 10k is... so, don't expect me to answer any complex question...

Hi can you please show the schematic of 10k ohm resistor connection ? Thanks

 

[Bitacaia]

Hi can you please show the schematic of 10k ohm resistor connection ? Thanks

Hi all the information i needed, i have found here:

https://forum.arduino.cc/index.php?topic=386749.0

Hope this helps. (In the mean time, i have reply to your private message.)