Question. Brought the boat home. Boat is on the trailer at the house. Doing some testing as I am going to rewire a few things and ran into this. If I test with my DVOM from the negative post on a battery to the hull I get 0volts with all the switches off. When I turn the switches on with nothing turned on in the boat I get same result. Normal and no voltage leaks. But when I start turning stuff on in the boat I start getting low voltage between the ground post of battery and hull, starts around .004 volts and climbs with the more stuff I turn on. Not sure if its normal, a lame DVOM, or a problem. It I turn on my radio and lights I will see around .010 volts from the negative of the battery and the hull. I will show .0 from a negative buss bar and the hull though. As I increase the load by turning on more stuff and turning the stereo up and increasing the draw from the batteries I will see it climb. It only reads from the battery bank supplying the power. I have got it as high as .3 volts with more stuff turned on. If isolate my house and my start banks from a positive standpoint (like they are normally) I will only see this on the bank battery supplying the voltage. If I turn on something tied to my start bank when it is isolated from the house (like the bilge or pot puller) I will start to see voltage off that bank doing the same test. If I turn off my house bank completely and bridge my start bank to my main panels I get it at the start bank and not the house, supply power from the house and I get it from the house. If I isolate the house from the boat and run something tied directly to the house with a switch (my crane winch) I see voltage when the winch motor is running. I am not sure if this is normal or if it is pointing to a problem. All my connections are real clean and all my buss bars are sprayed with battery terminal protectant and I don't see any signs of corrosion on connectors. Wondering if I am just paranoid or if thats a big deal? Like I say it is .0 with no load, when I start adding the load I see it. In fact I have 6 volt batteries in my house bank tied in parallel and series. If I go from the negative on one 12v set to the negative on the other 12v set I see the same thing as load is added. I don't see it from the other buss bars further from the bank I assume because of resistance but I am an armature trying to figure this out to prevent damage. My zincs all look like they are wearing normal. I do have some white speckles here and there on the boat but that is typical for an aluminum boat based on what I see on all the other boats. I have a few more tests to run but at this point I have bypassed 90% of the back bone wiring using jumper cables direct from the house bank to the buss bars under my dash for my main components and all the results are the same.