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Reading control voltage with arduino ADC, using accelstepper library to run the stepper. No need for feedback - just send 700 steps to high-resistance direction at startup and count steps from that position of 30ohm.
IMO a project for several evenings.
interesting but properly a real expensive product🙂
As I wrote above could maybe some sort of "higher voltage = higher resistance" thingy maybe a great solution. 1V = 1 Ohm - 10V = 10 Ohm. Du tere not exists some sort of Voltage controlled resistor contraption that could be made to do that? 🙂
As I wrote above could maybe some sort of "higher voltage = higher resistance" thingy maybe a great solution. 1V = 1 Ohm - 10V = 10 Ohm. Du tere not exists some sort of Voltage controlled resistor contraption that could be made to do that? 🙂
This is a very good question that no one have answered; well, I will, as they now are very cheap.
Yes, you can to a certain advantage use an electronic load. They come in one or two ch version.
You must check that voltages, current and resistance range is within the load´s DC capability.
You need to use a std. 15/35A bridge in between as it is only for DC loads. Also you must keep
the load "floating" vs GND. Choose "constant resistance measurement mode" The voltage will
be rectified peak values to be adjusted manually or within your terminal (USB) program.
There is a great advantage to be able to sweep the resistance load, as you will see how the
current limit, protection shutdown etc. behave using a separate OSC. Remember, many amps
have insufficent protection against low loads, whatever they say etc. use caution.
Yes, you can to a certain advantage use an electronic load. They come in one or two ch version.
You must check that voltages, current and resistance range is within the load´s DC capability.
You need to use a std. 15/35A bridge in between as it is only for DC loads. Also you must keep
the load "floating" vs GND. Choose "constant resistance measurement mode" The voltage will
be rectified peak values to be adjusted manually or within your terminal (USB) program.
There is a great advantage to be able to sweep the resistance load, as you will see how the
current limit, protection shutdown etc. behave using a separate OSC. Remember, many amps
have insufficent protection against low loads, whatever they say etc. use caution.