Introduction The basics What is electricity?; Volts, amps, resistance and power; Basic laws; AC and DC electricity Tools and measuring Tools for electrical work; Safety first; The multimeter; Making measurements in-circuit; Measuring high currents; Continuity, resistance and diode testing; Fault finding in low voltage systems Batteries Battery basics; Types of batteries; Specification, testing and maintenance; Charging the batteries; How many batteries?; Increasing capacity Make the connection Wire and wire size; Connections and connectors; Connecting thin wires Power management Alternators; Care, maintenance and fault finding; Sizing and upgrading; Intelligent chargers; Wind and water; Solar panels; Installing a mains charger; Hydrogen fuel cells; DC to DC converters; Regulating multiple sources; Monitoring battery and alternator currents; Power monitoring systems; Reducing consumption The DC system Battery switches; Battery switch configurations; Fitting a voltage sensing relay; DC distribution panels; Protection; Adding new systems; Installing permanent voltmeters and ammeters; Data recording over long periods; The engine and its electrics; Engine data monitoring; Engine data monitoring - set up and calibration; Starter motors; Digital switching AC mains on board Shore power; System installation; Mains protection; The earth system; Galvanic and electrolytic corrosion; Installing a galvanic isolator; Voltage inverters; Generators Networks Marine networks - NMEA0183; Talking to each other; Multiplexers and converters; Marine networks - NMEA2000; High speed data networks; Capturing what's left; Bringing it all together Installation projects Installing an AIS unit; Radar; Navtex and SSB receivers; Hall effect ammeter; Lightning protection; Underwater lights; Upgrading mast electrics Appendices Wire size matrix; Energy consumption analysis; Battery configuration and switching; Engine electrics; NMEA sentences Glossary Index Acknowledgements.