I have a project here at work that needs a load cell and I'm thinking of using an Arduino and one of these analog output load cells - iLoad Analog, Load Cell. I know they are kind of pricey, but I have some budget to work with.
Here's my question: The load cel is powered normally by its USB connection, but I'm not plugging it into a computer. Is the Arduinos 5 volt output regulated enough that I can use it to power the load cell? I guess what I'm asking is if it can substitute for USB power. Thanks. ~ bob
Nice looking product and probably a little pricey for hobbyist to play with I would think the +5vdc regulated output of the Arduino would be good enough to function. Perhaps there is a data sheet available to confirm it's voltage tolerance requirements. Otherwise a call to one of their application engineers would probably answer that.
which cell are you looking at? the iload mini communicates through an external interface. one of these interface allows for external 5V and provides an anlog output instead of USB power and output.
If you are plannng on using the other two they communicate through a usb interface and are designed to go to a computer (I don't know how they have an analog output, all I see is the USB serial port. They probably send the analog output in a string over USB). You could communicate to the arduino but you'd need to use the FT232 chip to bring the USB Serial down to a TTL Serial
I was looking at the iLoad analog because I think I will be above the load capacity of the mini. I see your point about the analog to usb direct translation issue. I will contact their apps guy and see what they have to say. I very much appreciate your input! Thanks.
Just to close this out cleanly... I spoke with an apps guy at Loadstar and the iLoad pro analog comes with stripped wire connections and outputs a .5 to 4.5 DC voltage that varies linearly with the load. There is a comparator in the load cel that cleans up small voltage fluctuations. Over time there is a drift in the calibration but the signal is supposedly very linear so it is simple to tare the cell in the microcontroller code. Apps guy thought that it should work very nicely with an Arduino. Thanks for all of your interest and support. ~ bob
I got the load cell and wired things up. The loadcell is not a cheap solution, but it is very accurate and works really well, even with my admittedly rookie programming abilities.
The system is basically a hand press that needs to exert a specified amount of force on some parts undergoing compression test. The system is a 250 lb capacity analog output loadcell into the analog input of the arduino. At no load a yellow LED lights up indicating more force is required. When the load is close to the required force the yellow led flashes and when it hits the required force a green led lights up. If the required force is exceeded a red led flashes and if it is greatly exceeded the red led goes solid and a piezo beeper sounds.
I'm thrilled that the system works and that the cost came in way under what a commercial system, or one contracted out, would have cost. Thanks for everyone's support! ~ bob
I would think the +5vdc regulated output of the Arduino would be good enough to function. Perhaps there is a data sheet available to confirm it's voltage tolerance requirements. Otherwise a call to one of their application engineers would probably answer that.