Answer to Question #97861 in Electrical Engineering for Mosaku John

Question

Explain the function of the following bridge circuits:
a) Inductance Bridge
b) Wheatstone Bridge
c) Capacitance Bridge
d) Wein Bridge

Answer 1

a) Inductance Bridge (or Maxwell bridge) It consists of four resistors, capacitor, and a coil and usually is used to measure the unknown inductance (with quality factor from 1 to 10) with high accuracy.

b) Wheatstone Bridge. It consists of four resistors and allows performing difference measurements. Three resistances are known and the 4-th is unknown. So after balancing the bridge one can find that unknown resistance. This type of bridges is widely applied in the transducers of nonelectrical values, such as optical, thermal, pressure etc. sensors. This bridge can provide extreme precision of measurements.

c) Capacitance Bridge. It is a modification of the Wheatstone Bridge with all resistance replaced with capacitors. By adjusting one of the capacitors and keep two constant one can measure the 4-th, unknown capacity. Also it can be used as pseudo galvanic isolation.

d) Wein Bridge. It consists of four resistors and two capacitors. In the balance state it allows to perform the measurements of it's parameters (capacity and resistance) with very high accuracy. Also it can be used as a generator with predefined frequency.