LAB2-2007v4_1.DOC - Curtin University

winetediousElectronics - Devices

Oct 7, 2013 (3 years and 8 months ago)

98 views

Curtin University of Technology


School of Electrical and Computer Engineering


Electrical
Systems

100 Laboratory




Expt No. 2 DC CIRCUITS



1

OBJECTIVE

To predict the performance of various electronic circuits and power networks requires
the engineer to
be

able to analyse the circuits and networks using a range

analysis
techniques.
A few of the fundamental analysis met
hods are investigated in this
l
aboratory
. This experiment introduces the basic concepts of dc circuit analysis using
Ohms and Kirchhoffs
Laws:



Ohms Law



Series Circuit



Parallel Circuit



Mesh Analysis



Nodal Analysis


2

APPARATUS


Dual DC Power Supply:

GP
C
-
3030

Digital Multimeter:


Fluke 175

Resistance:

1 x 100

,

1 x 120

,

2 x 150

,

1 x 470

,

1 x 820

,

1 x 1k

, 1 x 1.5

k

, 1 x 1
.8k

.

Br
ead Board



3

PRELIMINARY:



NOTE: You may need to consult you text,

research theory

in the library, o
r

the internet
before yo
u can complete the preliminary
. However by completing the preliminary
you will better understand the requirements of this laborator
y and be able to make
judgments on
the accuracy of

measured
results.

The preliminary is worth 25% of
your laboratory mark for each experiment.



3.1

Before coming to the laboratory neatly draw the circuit shown in Figure
2
.1
, 2.2 2.3
and 2.4 in your

log boo
k.


3.2

Calculate for Figure 2.1 the voltage acros
s each resistor,

the current through each
resistor as well as the voltage at points 1, 2, 3, & 4 with reference to ground GND.
Tabulate
the

results, leaving

space in
the

table
,

to enter the measured values
,

so

that
a comparison
can

be made between
the

theoretical and practical results


Electrical
Systems

100


Laboratory 2

__________________________________________________
____________________________


Version
4

February

200
6

2

3.3

Calculate for Figure 2.2 the vo
ltage across each resistor
, voltage across terminal
AB
,

the current through each resistor

and the total current drawn from the supply.
Tabulate th
e results, leaving

space in
the

table
,

to enter the measured values
,

so that
a comparison
can

be made between
the

t
heoretical and practical result
.


3.4

Calculate for Figure 2.3 the voltage across each resistor, voltage across terminal CE,
the current through
each resistor and the total current drawn from the supply.
Tabulate the results, leaving

space in
the

table
,

to enter the measured values
,

so that
a comparison
can

be made between
the

t
heoretical and practical result.


3.5

D
evelop the matrix equations for the
network
shown in Figure 2.4

using Kirchoff’s
Law methods of Maxwell’ Mesh Analysis and Nodal Analysis.
Analyse

the circuit
using each of the

methods
to find the voltage across each resistor, the current
through each resistor a
nd the voltage at points
A,
B, C, D and E

with respect to
ground (GND).

Tabulate the results, leaving

space in
the

table
,

to enter the
measured values
,

so that a comparison
can

be made between
the

theoretical and
practical results
.


Show all equ
ations and calculations for the

analys
is in
the

log book in a clear
and logical manner.


A logbook containing the answers to the preliminary questions will be marked by
the laboratory supervisor during the laboratory session.


4

LABORATORY:


4.1

Parallel

Circuit


4.1.1

After setting the DC power supply c
ontrol to independent, adjust the current
limit for both supply
A

&
B

to 300mA

(as in experiment 1)
.


Remember to change the position of the red
plug in lead on the

multimeter into the


400

mA socket, and to place the ammeter


in series with the
componen
t
.

(Set Ammeter to DC mode)


FIGURE 2.1


4.1.2

Connect the circuit, as shown in Figure
2
.
2
, using the dual power supply
output
A
.

Let
R
1

= 1

k

,
R
2

=
1.5 k

,
R
3

=
1.8 k

,
and

E
1

=
20 V


Electrical
Systems

100


Laboratory 2

__________________________________________________
____________________________


Version
4

February

200
6

3

4.1.3

Using

the Digital Multimeter measure the required measurement listed below.
Make sure to note the polarity of the voltage across each element and the
measured current direction.



The voltage across each re
sistor;



The current through each resistor;



The total current drawn from the supply.


4.1.4

Show
using measured results
that Kirchhoff's
C
urrent
L
aw holds for

Figure 2.1
.


4.2

Open Circuit I


FIGURE 2.
2


4.2.1

Connect the circuit, as shown in Figure
2
.
2
, using the dual p
ower supply

output
s

A

.

Let
R
1

= 1
50


,
R
2

=
150


.


4.2.2

Using the Digital Multimeter measure:



The voltage across each resistor;



The current through each resistor;



The voltage across V
AB
.


4.2.3

Show
using measured results
that Kirchhoff's
Voltage

L
aw holds for

Figure 2.2
.


Figure 2.3


4.3

Open Circuit

II

4.3.1

Connect the circuit, as shown in Figure
2
.
3
, using the dual power supply

outputs
A

.

Let
R
1

= 1
50

,
R
2

=
150


,
R
3

=
820


,

and


R
4

=
100




and
E
1

=
15

V
.


4.3.2

Using the Digital Multimeter measure:

Electrical
Systems

100


Laboratory 2

__________________________________________________
____________________________


Version
4

February

200
6

4



The voltage across each resistor;



The c
urrent through each resistor;



The voltage across V
CE
.


4.3.3

Using

Kirchhoff's
Voltage

L
aw
, shows that the result V
BE

is equal to V
CE
.




Figure 2.
4


4.4

DC
Crcuits and N
etworks

4.4.1

Connect the circuit, as shown in Figure
2
.
4
, using the dual power supply

outputs
A

.

Let
R
1

= 1
50

,
R
2

=
150


,
R
3

=
820


,


R
4

=
100


,
R
5

=
470


,
R
6

=
120


,
E
1

=
15

V

and
E
2

=
20

V.


4.4.2

Using the Digital Multimeter measure:

4.4.2.1

The voltage across each resistor;

4.4.2.2

The current through each resistor;

4.4.2.3

The vol
ta
ge at points A, B, C & D

with reference to GND.


All answers to preliminary questions and recorded experimental results should be
recorded in a logbook for inspection at the end of semester


5

R
EPORT TO INCLUDE
:


5.1

The answers to the following questions sho
uld be included in any laboratory report
discussion section.

5.1.1

C
omparison

tables

of measured and theoretical results

on a
results page
.

5.1.2

P
ossible sources of error that may exist between calculated and measured values.


A short form report
in an A4 folder must

be

handed to
the

laboratory supervisor
for marking at your next laboratory session.


End of Experiment

DISK:

CURTIN

DIR:

ELECTRICAL
SYSTEMS

100

FILE:

LAB
2
-
200
6v4
.D0C

AUTH:

N.D.KAYE

DATE:

FEBRUARY

200
6

FOR SEMESTER
1

& 2