Electrical System; Alternator - T T Est Alternator - Est; Battery - Test Battery - Test - Perkins 1103 Series Workshop Manual

48
Testing and Adjusting Section

Electrical System

Alternator - Test
Illustration 44
Typical wiring schematic for an alternator
(A) Terminal "B+"
(B) Terminal "D+"
(C) Terminal "W"
(D) Ground
(1) Electrical switch
(2) Dash light
(3) Ignition switch
(4) Battery
Warning Lamp Does Not Illuminate
The warning lamp for the charging system should
illuminate when the ignition switch is in the ON
position. Follow the steps below in order to test the
system.
1. Check the light bulb. Replace the light bulb if
the element is broken.
2. Use a suitable Multimeter to check the battery
voltage. Check the battery voltage with the
ignition switch OFF.
3. Check the voltage between the terminal (A) and
ground. The measured voltage should equal the
battery voltage.
4. Turn the ignition switch to the ON position. Check
the voltage between terminal (B) and ground. If
the voltage is more than 2 Volts the alternator
needs to be replaced.
i01899123
Warning Light is On When the
Engine is Running
1. Start the engine and run the engine at fast idle.
2. Measure the voltage between terminal (A) and
ground.
3. Measure the voltage between terminal (B) and
ground.
4. The measured voltage for terminal (A) and
terminal (B) should be 13 to 15 volts for a 12
volt system. The measured voltage for terminal
(A) and terminal (B) should be 26 to 30 volts for
a 24 volt system.
5. If the voltages do not match replace the
alternator.
6. Increase the engine to high idle. Turn an
electrical load ON.
7. Measure the voltage between terminal (A) and
g00931045
ground.
8. Measure the voltage between terminal (B) and
ground.
9. The measured voltage for terminal (A) and
terminal (B) should be 13 to 15 volts for a 12
volt system. The measured voltage for terminal
(A) and terminal (B) should be 26 to 30 volts for
a 24 volt system.
10. Replace the alternator if the voltage does not
match.
Battery - Test
Most of the tests of the electrical system can be
done on the engine. The wiring insulation must be
in good condition. The wire and cable connections
must be clean, and both components must be tight.
i01899136