I wish to analyze the current waveform through my stepper windings using a Rigol oscilloscope which I will be receiving shortly. I have no experience with an oscilloscope, and am looking for guidance.
The stepper is driven by a Pololu A4988 motor driver with voltage regulators, configured at 16 uSteps/full step;
The stepper’s specs:
- Stepper rated voltage: 12V
- Stepper rated current: 0.33A
- Supply voltage: 18VDC
- f= 10Hz (ie 10 full cycles of 16uSteps per full step per second)
I do not have a current probe, so plan to use a shunt resistor in series.
For shunt resistor value, my calcs so far if I am correct point to a 1 ohm resistance.
The only technique I have found on the internet involves the use the A -B differential method described here to measure voltage difference between two probes.
Is there another way to see the current waveform using this scope?
Thanks in advance for your responses!