Equipment List:
Fluke O-Scope
HP function generator
Bread board
assorted bananas and BNC cables
one inductor and one resistor
Goal:
To measure and study the relationship between the
phase
difference in the current and voltages in AC applications.
Procedure:
1. Construct an LR series circuit. Drive the circuits with
a
sinusoidal source.
2. Vary the frequency of the function
generator (through a broad range of frequencies, but high frequencies
might be more succesful) and with the scope, measure
the phase difference between the source voltage and the current (the
phase of the current is represented as the voltage across the
resistor).
3. Take at least 20 data points. Take
more data when the phase differences change quickly as you change the
frequency and less data when the phase difference does not change so
quickly.
4. Your instructor will show you how to measure the phase
angle. On the Fluke scopes, using the cursors makes this pretty
easy.
Analysis:
Use the computers to draw the graph of the phase
angle versus the frequency.
Conclusion:
With your instructors guidance, interpret your
graph.