Brandon_K
Member
Hey guys. I'm looking for an inexpensive way to integrate 4 load cells into a project. Right now, the project is using an Arduino with a HX711 amplifier / converter and it has been having numerous issues.
My load cells are 50kg, though I'm going to change them out for 10kg beams. Excitation voltage is 10-15v, I suspect I'll send it ~14v through a good regulator. Output is 2mV/V.
This is my first real step into load cells, so as I understand the specs above, if I send it 14v, I would get 28mV on the output.
I'm looking at using a Automation Direct Click for this project with a 16bit C0-04THM module. The module has a 0-39.xx mV range. If I'm understanding this correctly;
16 bit = 65536 \ 39mV range = 1680 units per mV. 1680 * 28 = a usable range of 47051. 10000g \ 47051 = .21g resolution? This would be with a 10kg cell. With a 50kg cell, it looks like I'll get a 1.05g per unit resolution.
Are there going to be any issues with this method? I'm not after big accuracy. The weights to be placed on the scale will vary in 15g increments and are known values.
My concern is I don't know what is going on internally with the thermocouple module. I assume I can scale this to whatever I want, though I'm not sure if the load cell (and the thermocouple module) are linear or non-linear. Linear scaling is easy, non-linear I'll have to learn how to do with the Click. I've been pampered and have had a non-linear scaling instruction available to me with the Productivity line.
Thoughts?
My load cells are 50kg, though I'm going to change them out for 10kg beams. Excitation voltage is 10-15v, I suspect I'll send it ~14v through a good regulator. Output is 2mV/V.
This is my first real step into load cells, so as I understand the specs above, if I send it 14v, I would get 28mV on the output.
I'm looking at using a Automation Direct Click for this project with a 16bit C0-04THM module. The module has a 0-39.xx mV range. If I'm understanding this correctly;
16 bit = 65536 \ 39mV range = 1680 units per mV. 1680 * 28 = a usable range of 47051. 10000g \ 47051 = .21g resolution? This would be with a 10kg cell. With a 50kg cell, it looks like I'll get a 1.05g per unit resolution.
Are there going to be any issues with this method? I'm not after big accuracy. The weights to be placed on the scale will vary in 15g increments and are known values.
My concern is I don't know what is going on internally with the thermocouple module. I assume I can scale this to whatever I want, though I'm not sure if the load cell (and the thermocouple module) are linear or non-linear. Linear scaling is easy, non-linear I'll have to learn how to do with the Click. I've been pampered and have had a non-linear scaling instruction available to me with the Productivity line.
Thoughts?