Electrical Engineering Analog Signals, Network and Measurement Virtual Laboratory Experiments

Measurement of Capacitance by Carey Foster Bridge            

Procedure


Figure 1: Circuit diagram for measurement of capacitance by Carey Foster Bridge
  • Set the voltage (V=12V) and Frequency (500Hz).
  • Choose the values of R1, L1, M and R4 from the capacitance box and the resistance box.
  • Run simulation. Observe the milivoltmeter pointer.
  • If "NULL" is achieved, click "Calculate" (on mode). At this condition, simulate again. Observe calculated values of unknown capaciatnce (C3) and unknown internal resistance (R3) of the capacitor. If better "NULL" is desired, click calculate (off mode) . Start from step 2.
  • Dissipation factor of the unknwown capacitor is defined as

$$ w * C * R \ Where, w = 2 * \pi * f $$