Hello Malda,
State Machine r2.X and r2+ use the Infineon ISO1H815G chip to drive valves. The terminals on the port breakout board are connected to the ISO1H815G's OUTNN and GNDBB pins (where NN is the channel number). The chip drives the valve while electrically isolating the high current switching circuit from the digital control interface. It also has several important features for robustness (e.g. thermal shutdown, reverse voltage protection, ESD protection, inductive load management).
The ISO1H815G is specified to work with supplies between 11V and 35V. The state machine's barrel jack is only used for valve driving, so you can attach a DC wall adapter within this range to set the valve voltage (12V or 24V solenoids are common). Unfortunately, the chip goes into under-voltage shutdown below 7V, so usage with 5V valves is not possible.
The weak 10V signal you're seeing is probably used by the chip for load detection. You'll see the correct voltage when a valve is connected.
Please follow up if you have any additional questions about the integrated valve driver!
Thanks,
Josh
