Throughout this site we use many technical terms, and given the breadth of readership our site enjoys, sometimes we are remiss and incorrectly assume everyone knows what we are referring to. For those that do not, here are some explanations of the technical terms use.
An instrument for measuring electrical current and hence the electrical output of the alternator. Instrument indicating the charge being put into the battery by the generator, also measuring the current being used by accessories, eg lights, heater, radio. Usually reads from + 30 through zero to -30 amps. A positive reading shows the battery being charged, a negative reading shows the battery draining.