I was able to use it to drive vintage military electronics
I bought this used in as-is condition. The fan was noisy, but the unit worked. I was able to find a manual online and set the parameters, and there are lots of them - making this a versatile unit, and set it up to power a 3 phase 400Hz WWII aviation gyroscope. It did this very well and the gyro spun up very nicely. Having variable frequency, I could run it at different speeds too. This unit is capable of up to 500Hz