Technical data

T
67
for each exercise.
When finished with the exercises, design your own circuits and have a lab partner troubleshoot them.
When designing a circuit for troubleshooting, it is common practice to insert test-points so that voltage
readings can be taken across each component in the circuit. It is also ideal for the troubleshooter to
have the ability to measure circuit current. Be sure to design the circuit in such a way that current can
be measured by simply removing the jumper wire connecting terminals 1 and 2 on the terminal block
and inserting the ammeter leads in its place as shown in Figure T-14.
When generating a fault on a lab partner’s circuit, make sure a resistance still exists in the circuit.
Failure to do this will create a dead short and possibly damage the power supply and test equipment.
he student may then begin troubleshooting the circuit using only a voltmeter or ammeter (no
ohmmeters), the connected terminal block on the testing jig, and a circuit schematic. Each step in the
troubleshooting sequence must be documented on the “Observations and Conclusions Table” provided
Complete the table below by assigning the correct colored wire to each test point.
Use a troubleshooting jig along with the illustration in Figure T-12 as a reference
Wire Color Test Point Connect to:
TP1 positive power supply output (+V)
TP2
positive supply to circuit
(ammeter connection point)
TP3 ground
TP4 voltage test point
TP5 voltage test point
TP6 voltage test point
TP7 voltage test point
TP8 voltage test point
Figure T-13
TP1 TP2
To power-
supply output
To circuit
Jumper wire
Replace jumper wire with ammeter leads
to measure circuit current.
Install jumper wire to connect circuit to
power supply for voltage measurements.
To power-
supply output
To circuit
0.00
V
A

TP1 TP2
+
–
Figure T-14