It’s not in the manual and I couldn’t Google it.
I wonder if it’s written on the back of the actual RME?
I thought electrical codes required the power consumption to be clearly marked on most appliances/devices
I recall the power supply being a 40 Watt supply but the RME would use much less than that. I would say at most 20-25 Watts. If you size for 40 Watts, you will be more than safe.