Cotty180 wrote:I have never used a multimeter, do they come with instructions and are they easy to use.
Get one and have a play with it - it's the best way to learn.
Think the analogy with water pipes - Voltage(volts) = pressure (potential), current(amps) = speed (flow).
A diode = a one way valve.
A voltage regulator = a water pressure regulator.
Too much current makes wires hot and fuses blow, too much voltage makes sparks. Stay away from anything over 50v.
Measuring a car battery with the V (voltage) scale should be 13.8 or thereabouts for a happy battery - in theory about 12V.
Measuring a car battery with the A (current) scale will fry the multimeter and smoke your leads, or blow a fuse in the unit.
Car batteries are high power items. They are low on volts (12) but high on current (600+). Power(watts) = volts x amps. Therefore a 24W lamp will use A = P / V = 2 Amps.
Another useful equation is: resistance(ohms) = volts / amps. Not everything has linear resistance - hence electronics are born...
Easy - see

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