HOSE-AIR 3937682 - Caterpillar

Table 1
Fault Conditions And Possible Causes
Current At Start-up The Voltage Is Below Specifications After 10 Minutes. The Voltage Is Within Specifications After 10 Minutes. The Voltage Is Above Specifications After 10 Minutes.
Less than the specifications Replace the alternator. Check the circuit of the ignition switch. Turn on all accessories. If the voltage decreases below the specifications, replace the alternator. -
Decreases after matching specifications Replace the alternator. The alternator and the battery match the specifications. Turn on all accessories in order to verify that the voltage stays within specifications. Replace the alternator.
The voltage consistently exceeds specifications. Test the battery. Test the alternator again. The alternator operates within the specifications. Test the battery. Replace the alternator. Inspect the battery for damage.
After approximately ten minutes of operating the engine at full throttle, the output voltage of the alternator should be 14.0 0.5 volts for a 12 volt system and 28.0 1 volts for a 24 volt system. Refer to the Fault Conditions And Possible Causes in Table 1.
After ten minutes of engine operation, the charging current should decrease to approximately 10 amperes. The actual length of time for the decrease to 10 amperes depends on the following conditions:
The battery charge
The ambient temperature
The speed of the engineRefer to the Fault Conditions And Possible Causes in Table 1.