My UPB2 is reporting 9.0A right now at idle. If I run the rotator and mirror focuser it peaks at 9.8A.
That's with 3 dew heater straps on the C14, as well as the camera dew heater. (I live in Seattle. Our state flower is mildew...)
This is without an OAG or OAG dew heater. That adds another 1.5A. I'm also musing putting my FocusLynx controller at the front of my scope since the Mach2GTO sadly doesn't have RJ45/CAT5 passthrough. Another 1.25A. So 12.5A so far. The UPB2 itself supports 20A - just needed to check the mount.
I don't specifically want to run 24V, but if the Mach2GTO had a low current limit (let's say 10A), I could run 24V 10A and step it down to 12V 20A with either a buck converter or transformer. I'm glad Roland confirmed this isn't needed.