ENGINEERING-43
Thevenin Equivalents
Lab-10
Lab Data Sheet – ENGR-43 Lab-10
Lab Logistics
Experimenter:
Recorder:
Date:
Equipment Used (maker, model, and serial no. if available)
Directions
1. Check out a DMM and Power/Probe Leads for the Power-Supply and DMM
2. Go to the side counter, collect resistors, “bread board”, and leads required to construct the
circuit shown in Figure 1.
3. Make the Measurements and Calculations needed to complete Table I
 Deactivate a voltage supply by removing its leads and replacing the supply with a short
to GND
 Calculate Vth, Isc, and Rth using the “Actual Values” for Vs, R1, R2 and R3
 Compute the third column of Table I (Vth/Isc) as at the Quotient of columns 1 & 2.
4. Return all lab hardware to the “as-found” condition
© Bruce Mayer, PE • Chabot College • 282217449 • Page 1
Figure 1 • Thevenin Equivalent Circuit. Vs = 9.00 Vdc. R1 = 2.5-4.9 kΩ. R2 = 5.5-8.5 kΩ.
R3 = 0.8-1.8 kΩ.
 Actual Values Measured by DMM
Vs =
R1 =
R2 =
R3 =
Table I – DMM Measurements for V & I
Value
Determination
VTH
ISC
VTH/ISC
RTH
RTH %
Calculated
Measured
%


n/a
RTH % = 100x(RTH – V/I)/(V/I)
%J = 100x(XJ,calc – XJ,meas)/XJ,meas
 Where Xj  one of:
o VTH
o ISC
o VTH/ISC
o RTH
Run Notes/Comments
© Bruce Mayer, PE • Chabot College • 282217449 • Page 2