Just measures current. For those of us that were interested in that sort of thing. Not necessary by any means but someday I want to fully instrument my ship and monitor and log voltages, currents, speed (maybe part of a governor circuit), gps position, pump current (maybe as part of an auto-prime/auto vapor lock fix), voltages, servo commands, number of rounds fired from each barrel, etc. we will see if I ever have time to do that.
Good luck with all of that Greg....Im still looking to get my first ship on the water. I think you may be ahead of me []
Well, I've built plenty of ships over the years... now my interests lean more decidedly towards r&d for either better reliability, better efficiency, more automation, and other things I can teach myself.