When checking the details of an electrical system, it is necessary to have an understanding of the basic electrical terms: voltage, current and resistance.
Voltage is measured in volts (B or V), current strength - in amperes (A), resistance is in ohms (Ohm). Vehicle voltage generally refers to the voltage of the battery (AB), i.e. a constant voltage of about 12 V. The battery voltage depends on its charged and on the outside temperature and varies from 10 to 13 V. The voltage is supplied to the electrical equipment system, in addition, from the generator, and it is about 14V at medium speeds.
concept «current» or «current strength» rarely used in auto electrics. The amperage is usually marked on the fuses and corresponds to the maximum current that can pass through the fuse without blowing it.
Wherever an electric current flows, it experiences electrical resistance. It depends on many factors, the cross section of the wire, its material, temperature, etc. The amount of resistance, in particular, has a great influence on the operation of the ignition system.