Appendix to Honeyman and Robinson: Glossary of Terms

AC (alternating current) — the kind of power that typically comes from a wall socket.

amps (ampere, amperage, A) — the amount of electricity that flows at a particular time; Amps = Watts/Volts.

amp hours (AH) — see watt hours.

blocking diode — a means of preventing backflow of electricity so that when the power source is no longer charging up the power storage, the power will not flow back into the power source.

charge regulator (also known as a charge controller) — a device that monitors the amount of electricity that flows from the solar panels to the battery, preventing the battery from overcharging, and preventing the loss of electricity through backflow into the solar panels; some charge regulators also prevent the user from overdraining the battery.

DC (direct current) — the kind of power that typically comes from a vehicle battery; this is also the kind of power utilized by many electronic devices such as laptops, which have built-in adaptors that convert AC electricity into DC.

deep cycle battery — a durable battery designed to be drained of the majority of its charge each cycle.

fuse — a small glass tube containing wires that burn out before a dangerous current reaches the device, thus preventing an electrical device from being overcharged.

inverter — a device that converts DC electricity into AC.

lead-acid battery — a standard battery, such as a car battery, that should be drained only of thirty to forty percent of its charge.

milliamps (mA) — 1 amp is equal to 1000mA.

multi-meter — a handheld device that can measure volts and amps.

parallel circuit — a circuit in which the parts are wired together in a bunch. All positives are wired together and all negatives are wired together, thus increasing the amperage of solar cells, or the available amps for batteries.

polarity — the positive (+, red) and negative (-, black) ends of a powers source.

serial circuit — a circuit in which all the parts are wired in a continuous line, negative to positive to negative to positive, thus increasing the voltage of a power source.

volts (voltage, V) — a measure of electrical potential or force. It is roughly analogous to the idea of water pressure, where the electricity is the water, and the voltage is the water pressure; Volts = Watts/Amps.

watts (W) — a measure of how much power a device uses (or produces) at any given time; Watts = amps x volts.

watt hours (Wh) — a measure of how much electricity a power reservoir has or can store. Divide by volts to convert to amp hours.