Graph 20.2 now can be used as a calibration chart for the shunt circuit of Fig. 20.4.
Now set the O-IO-kll potentiomet~r (Rx) to three random values and record the
resulting value of 1Min column one of Ta
Calculate the currents fRI' fR2' and fR3
using the measured voltage and resistor values
and insert in Table 14.3 as the measuredvalues. Be sure to include a minus sign if the current direction is opposite to that defined by the pola
NORTON'S THEOREM AND CURRENT SOURCES
Vary the supply voltage until the DMM indicates the value IN from part 2(b). Record
the values of E and IN in Fig. 13.6(b). Next remove the DMM and, using it as an ohmmeter, set the
Do the results verify the source conversion theory?
~So\"T.e, ~ ~c. fCl.rCAMT
For thenetworkof Fig. ~
(a) Find INby determining the reading of an ammeterplaced betweenpoints a and b.
EXPERIMENT dc 13
(k) Does the plot of Graph ~reveal
IL is fairly constant for the range of chosen
tr"'" , ~
yo ~ .
(I) Wouldyou consider networkof Fig. l~a
figurationof Fig. ~? Makea
R71J .2.'4~.n., E71J 3$.~ tJ
(c) Is the power determined in part (b) the maximum power that could be delivered to a reo
sistor betweenterminals a andb? If not, what is the maximum power?
How do the calculated and measured values compare?
E ~ cc.R.e~
"P().;t.~.AQt.) .R/L 4 '\fa.c .L
(d) Now plot PL and VLversus RLto confirm once more that the condition
Referring to the plot of Graph 12.1, what value of RL resulted in maximum power
transfer to RL? Record in Table 12.5.
THEVENIN'S THEOREM AND MAXIMUM
How do the theoretical measured
THEVENIN'S THEOREM AND MAXIMUM
(d) Turn on the 12-V supplyof Fig. 12.2, measure voltage VL,and record in
Table12.3.Using the measured
calculate currentIL andrecordin Table12.3.
EXPERIMENT dc 12
Manufacturer and Model No.
Through the use of Thevenin's theorem, a complex two-terminal, linear, multisource dc network
can be replaced by one having a single sourc
1. For the network of Fig. trf:F;:' J 1, g
FIG.J.9=& J 1.:&
(a) By inspection (meaning no calculations whatsoever) using the superposition
theorem, which source (II' Ib or E) would appear to have the most impact on the
El (part(a Calculated
If .37 v 1.lJo.34- 17 v
If .37 V I't.lCf v
12.fI~ V a'3v
EXPERIMENT dc 11
Turn on the supply 2 and measure the currents 1\, 12,and 13' Check your measure"rve!lts by noting whether Kirchhoff's current law (13= 1\ + 12)is satisfied. Record the results in
How do the calculated and measured values of
POWER RATINGS OF RESISTORS
6. What percentage was that power of R1s rated power? Given the results to questions 4 and
5, is it safe to operate this circuit?
7. In Fig.10.3, the voltage Vsource had to be rais
EXPERIMENT dc 10
Slowly increase the power supply voltage, Vsource, until Vload reads its calculated maximum value. It may not be possible to obtain exactly the above calculated voltage of Vload. Get as
1. Calculate the time constantof a seriesR-C circuit.
2. Calculate the circuit current and the capacitor voltage for various R-C
circuits after five time constants.This in effect def
(e) Disconnect supplyandmeasure voltageacross disconnected
Is therea reading?
C " QY~ IS sfor-e.c,(
; 1.'1Th -e. C~ pac,(
l/1o+-e:. V ~ ~/ c.
(f) Shortthe capacitor
Imeter movement (mA)
f r II! I ! IIIII I,II I,IIII ! I
11 , t I ~ f,
I , I , ~I
Draw a meterscale for your ohmmete
Construct circuit of Fig. 20.2.
Connect the probes points PI and P 2 together and adjust the power supply until the
meter movement reads I rnA. Hold the probes apart (open-circuit
EXPERIMENT dc 19
How does this level of the current I compare with the calculated and measured values of the
1:1",'(;3 \Co): 1"7, ~ A
f'","T "3<.e.) 1~,lomrA
2. Referringto Fig. 19.1,if Rl and R
WHEATSTONE BRIDGE AND Il-Y CONVERSIONS
(b) Calculate the source current I and the voltage Vab
using any method other than a
~- Y conversion (that is, mesh analysis, nodal analysis, and so on). Record the results in column
one of Table 19.4. Use RA = R
1. Becomefamiliar with the construction and terminal characteristics of the
2. Usea commercialWheatstonebridge to measurean unknown resistance.
3. Apply a ~- Y conver
(a) Construct networkof Fig. 19.3.Insertthe measured
setthe potentiometer the maximumresistance
Whatconclusions you draw from the preceding
(a) Construct circuit of Fig. 18.6.
~k.a + R2measured
What is the theoretical valu~ .oftbe voltage V2? Use measured
DESIGN OF A dc AMMETER AND VOLTMETER AND METER LOADING
Testing the Designed Voltmeter:
(b) Connectyour newly constructedvoltmeter in parallel with a voltage,source
and the DMM as shown in Fig. 18.4. Set the variable resistorto Rswith your DMM
EXPERIMENT dc 18
The basic metermovement a current-sensitive
device.Its constructionconsistsof a coil suspendedin a ma