Introduction to Electrical & Electronic Devices
In this exercise, you will:
- ..learn to use digital and analog multimeters to
current, resistance, capacitance.
- ..connect several resistors together in series and
parallel to create equivalent resistors of another
- ..use the high voltage power source to produce
current with a required amount of voltage.
Record your measurements either in the tables or on
the back of these sheets.
MEASUREMENTS & CALCULATIONS:
- Measure the AC voltage generated by the digital function
generator using the digital multimeter. Set the function
generator on the first
setting (sine wave), and the multimeter on AC voltage.
The measurement range should be set on 20 V since
you will create an AC voltage of 2V, and the probe
wires should be plugged into the COM (black) and
VΩ (red) sockets. Start out with
the amplitude knob of the function generator turned
all the way to the left (0V). The
voltage can be measured by touching the meter's probes
to the metallic inner part of the red and
black sockets on the function generator. The frequency of
the AC from the generator will not strongly affect the
voltage. Set it to 900 Hz. Then adjust the amplitude
so that the voltage reads about 2V on the meter.
Record the measurement.
- Without changing the settings on the function
generator, measure the same thing using the analog multimeter.
The left knob should be set on "AC volts only," and the
range should be set on 2.5V. The probe wires should be
plugged into the COMMON (black) and + (red) sockets.
Record the measurement.
- Use the digital meter to measure the resistance across
the lengths of copper and copper-nickel wire on the coils.
Measure all the resistances in the table.
After measuring these, calculate for the first four, what each
resistance should be according to:
The resistivity of copper is 1.7 × 10-8 Ω m.
Remember that A is the cross-sectional area of the wire. The
area of a circle is πr² (and r should be in meters).
|Type Wire||Gauge||Length (m)||Resistance (Ω)||Calculated||% Diff
|Copper||22 (.644 mm diam.)||10|| || ||
|Copper||28 (.321 mm diam.)||10|| || ||
|Copper||22 (.644 mm diam.)||20|| || ||
|Copper||28 (.321 mm diam.)||20|| || ||
|Copper-Nickel||22 (.644 mm diam.)||10||
|All wires in series||------||70||
- Calculate the percent difference between the measured and calculated
- Use the digital meter to measure the resistance of
one each of the following resistors: 15Ω, 100Ω,
470Ω, 1000Ω. The range of the meter should be
set appropriately, depending upon the resistance being measured.
- Now put two of the resistors (any two of different resistance)
in parallel and measure the
resistance across them.
- Given the resistance that you measured for each of the
two resistors individually, compute what the resistance of
the two resistors should be when they're in parallel.
- Find the percent difference between the measured and
- Use the digital meter to measure the capacitance of the 4
capacitors. Refer to the instructions for the meter to find
out how to do this.
- Measure the capacitance of any two of the capacitors in
|combo|| || ||
- Calculate the theoretical capacitance of the combination.
- Find the percent difference between the measured and calculated