[EricH]

I followed it OK.

How it works: you take the ground wires (black) of the solenoid and run them back to the distribution board's power return. Then you take the other wires of the solenoid and run them to the Spike, attaching one to each of the two output connections on the Spike. Not sure how you'd program it, though--Alan would know that.

Or, the simpler option, use the Solenoid Breakout and avoid the Spike altogether.