When equipment fails, boat owners often say they don’t know anything about electricity. They won’t touch any of the wiring. This is unfortunate because a majority of the time, faults are caused by loose connections, corroded wiring or blown fuses—all things that are simple to troubleshoot.
The trick is being able to “see” why the electricity is not flowing. You have to know where to look. Adding a multimeter to an onboard toolkit is key to understanding what’s happening.
A LOOK AT ELECTRONS
Electricity requires a source of power. This source can be a battery charged with direct-current energy from an alternator, solar panel or charger; or the source can be alternating current from a generator or inverter.
DC energy, unless it’s intended for propulsion, is generally low voltage: less than 24 volts. If it’s less than 50 volts, DC is considered non-lethal, although it can cause welding-level sparks and heat if wires are shorted (if a bare positive wire touches a bare negative wire or other grounded component).
AC, on the other hand, is high voltage, at 120 or 240 volts. The threat of electrocution is much more present, in addition to
