3618 Engine Caterpillar

This procedure can be performed when the engine is stopped or when the engine is running.

1. Adjust the calibration tool in order to produce a signal that simulates 112 °C (234 °F) from a type K thermocouple. Refer to the instructions that are provided with the tool.

2. Turn OFF the power for the control system.

3. Disconnect the wiring for the number one main bearing's thermocouple from the terminal strip in the engine mounted junction box. For the locations of the terminals, refer to the engine's electrical Schematic.

4. Connect the calibration tool to the terminals in the junction box for the number one main bearing's thermocouple.

5. Turn ON the power for the control system. Activate the calibration tool and send the 112 °C (234 °F) signal to the control system.

   If the control system is operating correctly, an alarm will be activated after 5 seconds and a shutdown will be activated after 30 seconds.

   If the alarm and shutdown are not activated within the time period, verify the temperature reading on the monitoring system. The signal may be weakened by the line loss. Increase the calibration tool's signal by a few degrees. If this does not produce the alarm and shutdown, make sure that the protective system is programmed with the correct setpoints.

6. Acknowledge the alarm and reset the control system.

7. Disconnect the calibration tool from the terminal strip. Reconnect the wiring from the disconnected thermocouple to the terminal strip.

8. Repeat Steps 1 through 7 for the other nine main bearings' thermocouples.