Here are a few of the most commonly used off-grid solar electrical system terms:

Charge controller: The charge controller feeds current into the battery bank at the required voltage. Good charge controllers draw the best performance out of the batteries and are very important for economics because they influence efficiency.

Battery bank: The battery bank is typically made up of six or more individual batteries connected with stout cables in either series or parallel arrangements.

Inverter: The inverter changes DC to AC voltages suitable for use with household equipment. An inverter is optional if you use DC loads exclusively.

DC loads controller: You may be using both DC (boat, RV, and auto appliances) and AC loads (standard household appliances). The DC loads controller maintains the proper currents and voltages into the DC loads.

AC generator: As a backup power supply, the AC generator isn't strictly necessary but is usually part of any off-grid system in order to prevent blackouts when the sun is weak for extended periods.

Transfer switch: The transfer switch alternates the power source between either the inverter output (when battery power is available) or the AC generator.

AC loads controller: This device includes appropriate fuses and switching means and maintains the voltages and currents used by the AC appliances connected to the system.