ENGINEERING-43
Parallel Circuits  Current Dividers
Lab-03
Lab Data Sheet – ENGR-43 Lab-03
Lab Logistics
Experimenter:
Recorder:
Date:
Equipment Used (maker, model, and serial no. if available)
Part-1 Directions – Current Dividers
1. Note that in this and ALL OTHER Laboratory Exercises ENGINEERING UNITS must
accompany ALL Data-Entries and Calculated-Quantities
2. Check out a DMM and Red/Black measurement Leads.
3. Go to the side counter collect resistors, “bread board”, and leads required to construct the
circuit shown in Figure 1.
4. Make the DMM-Measurements1 and Calculations needed to complete Table I and Table II
 Calculate the currents and resistances using the ACTUAL, or DMM, measured values
for V, I, and R.
 Calculate the Δ% for the measured value as compared to the calculated from theory for
an arbitrary quantity, Q, as
% Q 
Qcalc  Qmeas 100%

Qmeas
1
1
CAREFULLY Select the DMM range such that meter displays at least THREE (3) digits, and FOUR digits if
possible. All DMM measurements should be reported to MAXIMUM POSSIBLE number of significant figures.
© Bruce Mayer, PE • Chabot College • 282217817 • Page 1
NOTE
The Ammeter MUST be connected in series with NO potential across it; i.e.,
do NOT connect the ammeter ACROSS Vs or any R.
Figure 1 • Current Divider. Vs = 9.00 Vdc. R1 = 1.4-2.5 kΩ. R2 = 3.0-4.8 kΩ.
Table I – Current Divider V/I Measurements and Calculations

COLOR-CODED Resistor Values & Tolerances
R1 =
R2 =

Actual (DMM) Values
Vs =
R1 =
R2 =
Value Determination
IT
I1
Calculated
Measured
%

% = 100x(Icalc – Imeas)/Imeas
© Bruce Mayer, PE • Chabot College • 282217817 • Page 2
I2
Table II – Current Divider Resistance Calculations
Value Determination
RT
R1
R2
Calc by V/Imeas
DMM Measured
%

% = 100x(Rcalc – Rmeas)/Rmeas
Part-2 Directions
5. Modify the previous circuit to the configuration shown in Figure 2
6. Make the Measurement and Calculations needed to complete Table III
7. Return all lab hardware to the “as-found” condition
Figure 2 • Current “Trivider”. Vs = 9.00 Vdc. R1 = 0.6-1.6 kΩ. R2 = 1.7-2.8 kΩ. R3 = 2.94.8kΩ.
Table III – Voltage “Trivider” V/I Measurements and Calculations

COLOR-CODED Resistor Values & Tolerances
R1 =
R2 =
R3 =
© Bruce Mayer, PE • Chabot College • 282217817 • Page 3

Actual Values
Vs =
R1 =
R2 =
R3 =
Value Determination
IT
I1
I2
I3
R2
R3
Calculated
Measured
%

% = 100x(Icalc – Imeas)/Imeas
Table IV – Current “Trivider” Resistance Calculations
Value Determination
RT
R1
Calc by V/Imeas
DMM Measured
%

% = 100x(Rcalc – Rmeas)/Rmeas
Run Notes/Comments
Print Date/Time = 29-May-16/03:59
© Bruce Mayer, PE • Chabot College • 282217817 • Page 4