[Al Skierkiewicz]

Peggy,
What might be more understandable is that DC voltages can be added together. 12+12=24 or 8+8+8=24, or 2+6+12+4=24, etc. So if you can store 12 volts in an electronic device and then add it to the battery voltage you can have more than the battery voltage. The boost convertor that is being described performs this task. The cool part is that it can also compensate for lower battery voltages so that it always produces 24 volts even if the battery should fall to 4.5 volts simply by adding voltages in the storage device. It is sort of like having a bucket that stores water but the bucket has a hole in it. You keep putting water into the bucket until it full and then you just need to add small amounts of water to keep it full. This conversion does 'cost' something and that is a limit in the amount of current that can be produced. In the case of this circuit in the PD, 1 amp is the maximum current that can be used without affecting the output voltage. That is why the robot rules allow only the Crio and one and only one solenoid module to be connected to the 24 volt output of the PD. Anymore than that, and the 24 volts may be compromised to the point that the Crio will shutdown.