Looking through the summaries, Pro has higher input voltage and current. S1 has a brake resistor circuit. I’m curious about any other nuances between the two products, is there anything else that warrants the two different versions and the price difference?
The ODrive Pro is our high-power offering designed for rugged industrial and high-EMI usecases. Specifically, it offers the following over S1:
Higher supply voltage - S1 is 50V max, and Pro is 58V max
Higher output current - S1 is 40A/80A continuous/peak, Pro is 80A/120A continuous/peak
SSI encoder support
Isolated encoder and hall sensor feedback (useful for high-EMI environments)
Isolated CAN
Onboard fan control
In general, S1 is designed to be a performance-per-dollar focused solution for the majority of relevant motor control use cases, while the Pro is designed for more intensive industrial use cases where things like isolation and high EMI robustness is critical. If none of the advantages of the Pro over the S1 is relevant to you, the S1 is a great choice – they both run the same firmware and algorithms, so performance will be identical.