Villanova University
ECE 2053 Electrical Engineering I Lab
Spring 2012
C. McKeough
Overview – The Fundamentals of Electrical Engineering Lab I
This handout lists the course objectives and discusses the lab workstations, protoboard, laboratory
safety, laboratory notebook, data recording and general information.
Course Objectives
The objectives are:
1. To develop skills in using laboratory instruments for measuring dc voltage and current, ac
voltage and current, resistance, capacitance, and inductance.
2. To learn how to make signal measurements using an oscilloscope.
3. To enhance physical understanding of circuit concepts such voltage, current, Kirchhoff's
laws, and the characteristics of circuit elements.
4. To be introduced to electronic devices.
5. To be able to draw and simulate circuits using PSpice.
5. To learn how to record experimental results and keep a laboratory notebook.
6. To apply laboratory skills to the verification of design requirements.
Laboratory Workstations
Each workstation has a number tag and is equipped with two basic pieces of measuring equipment: a
digital multimeter (DMM), and an oscilloscope. Two other pieces of equipment provide signals: a dc
power supply and a signal (or function) generator. If any unit is not working, do not remove the
equipment, but rather inform the lab instructor.
Each workstation also has a circuit breadboard which is referred to as a protoboard (PB).
The Protoboard
Electrical circuits are constructed on the protoboard. It consists of a molded plastic array of holes into
which wires and device leads are inserted. A typical board is shown below in landscape orientation.
Socket
Strip
Gutter
Bus strip
The board consists of bus strips and socket strips. The bus strips are inside the red and blue horizontal
lines. All holes in the same row of the bus strip are electrically connected together. The socket strips
overview - the fundamentals of ee lab i jan 20.docx
1
have a gutter down the middle. The 5 holes in a column above a gutter are electrically connected
together, and the 5 holes in a column below a gutter are electrically connected together.
The holes will accept AWG1 No. 24 wire, and device leads up to the thickness of a ½ watt resistor.
Safety in the Laboratory
It is important to perform experimental work in an orderly and safe manner in order to avoid electrical
shock. Current is the cause of a shock’s intensity. Remember this fact: current through the body between
0.1 ampere and 0.2 ampere is lethal.
The following safety rules are very important and should be adhered to in the laboratory.
1. Never work alone in the laboratory. One other person should be there in order to aid the victim or
to obtain additional help.
2. Instruments and power tools connected to the 120-volt ac power line should be grounded through
a three-prong receptacle.
3. Before touching wiring, disconnect or shut off power and ground high-voltage points.
4. If possible, place only one hand on the circuit on which you are taking measurements.
5. Do not stand on metal surfaces or wet concrete.
6. Never use electrical equipment if your skin is wet.
7. Always place hot soldering irons in their proper holders. Disconnect the iron when not in use.
8. When cutting or stripping hookup wire, point the cut end of the wire away from a person’s face.
Laboratory Notebook
Each student is required to have a bound notebook. It should be 5 in. by 8 in. and inexpensive – see
illustration.
Use the notebook to record lab procedures, data, analyses of each experiment, and reference information
on test and measuring equipment, and electronic devices. The notebook is to be a running account of
what happened during the experiment. Document the notebook while the experiment is progressing, not
afterwards.
1
American Wire Gauge.
2
Before coming to lab, prepare the notebook with the following:
The title of the experiment
The date
The objectives
Appropriate theory and background material
During the experiment, summarize the procedures that you are using by writing a sentence or two next
to the data that you are recording. Include complete wiring diagrams and lists of equipment with their ID
number.
Data that is normally in graphical form should be plotted in the notebook as the data is being recorded.
Finally, organize your notebook in such a manner that someone with a similar background can follow
the work in your notebook and duplicate it.
Data Recording: Units and Symbols
Recorded data should include the magnitude of the quantity and its proper unit. The System
International d ‘Unites (SI) units and unit symbols are listed in Table 1.
Table 1 Electrical Units and Symbols
Quantity
Voltage
Resistance
Inductance
Unit and Symbol
volt V
ohm Ω
henry H
Quantity
Current
Conductance
Capacitance
Unit and Symbol
ampere A
siemens S
Farad F
In electrical engineering practice, most units have a decimal multiplier, e.g., current may be measured in
milliamperes (mA), or resistance may be measured in megohms (MΩ). The SI decimal multipliers are
shown in Table 2.
Table 2 Multipliers
Prefix
milli
micro
nano
pico
Magnitude and
Symbol
10-3 m
10-6 μ
10-9 n
10-12 p
Prefix
kilo
mega
giga
tera
Magnitude and
Symbol
103 k
106 M
109 G
1012 T
As an example of proper usage, a voltage reading (or calculation) of 22.8 x 10-4 volts should be
recorded as 2.28 mV. The idea is to use kilo (k), milli (m), micro (μ), etc., for all data. Think SI!
3