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A SHUNT is a physically large, low-resistance conductor connected in parallel with the meter
terminals. It carries the majority of the load current so that only a small portion of the total current will
flow through the meter coil.
An AMMETER measures current and is always connected in series with the circuit being measured.
An ammeter should have a low resistance so that the effect of the ammeter on the circuit will be kept to a
minimum.
VOLTMETERS are used to measure voltage and are always connected in parallel with the circuit
being measured. A voltmeter should have a high resistance compared to the circuit being measured to
minimize the loading effect. Voltmeter sensitivity is expressed in ohms per volt.
OHMMETERS are used to measure resistance and to check continuity. An ohmmeter is electrically
connected in series with the resistance being measured. The ohmmeter range, which allows a midscale
deflection, should be used.
A MEGOHMMETER (MEGGER) is used to measure very high resistance, such as the insulation
of wiring.
A WATTMETER is usually an electrodynamometer and is used to measure power.
