Thanks for the answer. On the current measurement side is it the pass device of the current sensor that is the limiting factor? Also can take offline.

Thanks for the response. Please contact me directly to discuss details and arrange for shipment.

Thanks for the presentation. Can you point me to the application note on the J2121A, as I am only finding the 2 page brochure and manual? Since my initial post I have been able to work on the setup and measure several inductors. The setup is working, but I have ran into a couple challenges: The PFC inductors are in the range of 100uH to 1000uH, which is much larger than you typically demonstrate. At impedances above 50-100 Ohms it looks the measured current drops to the noise floor. Measuring a lower value 40uH inductor looks similar but with the measurement noise coming in at a higher frequency. Turning the drive level up seems to help, but this is limited as increasing it too far the test signal starts to intersect 0V which brings about other challenges. The setup is using 3 P9610A in parallel as described, in the manual to deliver the required current. When in constant current mode the supplies are not stable testing inductors of this value range. Moving back to constant voltage mode is stable and the static sharing is pretty good. Dynamically there is some imbalance (trace 1 is the voltage into the P2121A and traces 2-4 is the current being delivered by each supply). No problems have been noted yet from this, but I have not investigated the sharing yet at 20A currents. Is there an alternate compensation network option for these supply to improve their operation in this configuration and these loads?