Moving Coil Galvanometer, Ammeter & Voltmeter
An electromechanical instrument that measures small currents using magnetic torque on a pivoted coil, converted to an ammeter or voltmeter using shunts or series resistors.
Governing formula
τ = N I A B = k θ; Ammeter: S = I_g G / (I - I_g); Voltmeter: R_s = (V / I_g) - G
SI unit
A (Current), V (Voltage)
In depth
Connecting a low shunt resistor S in parallel converts a galvanometer into an ammeter. Connecting a high resistor R_s in series converts it into a voltmeter.
Examples in the real world
Analog panel meters measuring current and voltage on industrial electrical test benches.