Volts vs Amps -- the difference
At the risk of assuming, it may help give you a bit more ease, also, just to know what the difference is. Volts is electrical "pressure", so to speak, and amps is the flow of electricity as it is being used. An analogy is the plumbing in your house. If you put a pressure meter on the system, you will see the pressure measured in the 80 pounds per square inch range. This is like volts -- potential for flow, but not flow, itself. Now, if you go look at the city water meter by the curb, you will see that it measures cubic feet of flow, not pressure. If you open a faucet and watch the city water meter with a stopwatch, and write down how many cubic feet has flowed in a minute, then you have measured the flow rate. This is like amps -- the flow rate.If all your faucets are closed, but you still see the water meter clicking off flow, you know you have a problem with a leak somewhere, but if it is idle, then everything is OK. The same thing with your boat. With all of your electrical stuff turned off, the volts (pressure) should be at 12 volts or slightly higher, but not by much, and your amps (current flow) should be at zero. As you turn on lights and so forth, the amps will measure more and more current flow as you add more things to draw from the system.