3606, 3608, 3612 and 3616 Engines and C280-12, C280-16, C280-6 and C280-8 Marine Engines Generator Monitoring System Caterpillar

Test Procedure

System Operation

A resistance temperature detector (RTD) measures the change in electrical resistance as a function of temperature. As the temperature increases the resistance increases. As the temperature decreases the resistance decreases. The resistance of a RTD varies linearly with temperature.

The signal is routed from the engine mounted junction box to terminals in the control panel. The RTD module converts the signal into the parameter.

The signal is used in order to trigger alarms and the signal is used in order to display the parameter.

Illustration 1	g00563641
Schematic of the RTD

Illustration 2	g00562911
Schematic of the RTD

Functional Test

Note: The 163-0096 Diagnostic and Calibration Tool can be used in order to troubleshoot this component. Refer to the "Owner's Manual" for more information.

1. Check the electrical connectors and check the wiring.

   Show/hide table

   Bodily contact with electrical potential can cause bodily injury or death. To avoid the possibility of injury or death, ensure that the main power supply has been disconnected before performing any maintenance or removing any modules.

   1. Disconnect the power supply.

   2. Check the electrical connectors and check the wiring for damage or bad connections.

   3. Verify that all modules are properly seated.

   4. Verify the status of the LED on the SLC 5/04 - 5/05.

      The results of the preceding procedure are in the following list:

      • All of the components are fully installed. All of the components are free of corrosion. All of the components are free of damage. All of the modules are properly seated. Proceed to 2.

      • The components are not fully installed. The components are not free of corrosion. The components are damaged. All of the modules are not properly seated. Repair the component. Verify that the repair resolves the problem. STOP.

2. Check the RTD.

   Show/hide table

   Bodily contact with electrical potential can cause bodily injury or death. To avoid the possibility of injury or death, ensure that the main power supply has been disconnected before performing any maintenance or removing any modules.

   1. Disconnect the RTD from the wiring harness. This is done by removing the connector head of the RTD.

   2. Measure the resistance on the sensor. Measure the resistance between the following terminals: Terminal 1 and Terminal 2.

   3. Use Table 1 for engine RTDs in order to determine if the RTD is functioning normally. Use Table 2 for generator RTDs in order to determine if the RTD is functioning normally.
      Show/hide table

      Table 1

      Engine RTD (European Curve)
      Temperature	Resistance, Ohms
      0 °C (32 °F)	100.00
      10 °C (50.0 °F)	103.90
      20 °C (68 °F)	107.79
      30 °C (86 °F)	111.67
      40 °C (104 °F)	115.54
      50 °C (122 °F)	119.40
      60 °C (140 °F)	123.24
      70 °C (158 °F)	127.08
      80 °C (176 °F)	130.90
      90 °C (194 °F)	134.71
      100 °C (212 °F)	138.51
      110 °C (230 °F)	142.29
      120 °C (248 °F)	146.07
      130 °C (266 °F)	149.83
      140 °C (284 °F)	153.58
      150 °C (302 °F)	157.70

      Show/hide table

      Table 2

      Generator RTD (American Curve)
      Temperature	Resistance, Ohms
      0 °C (32 °F)	100.00
      10 °C (50.0 °F)	103.97
      20 °C (68 °F)	107.93
      30 °C (86 °F)	111.88
      40 °C (104 °F)	115.82
      50 °C (122 °F)	119.75
      60 °C (140 °F)	123.66
      70 °C (158 °F)	127.56
      80 °C (176 °F)	131.45
      90 °C (194 °F)	135.33
      100 °C (212 °F)	139.20
      110 °C (230 °F)	143.06
      120 °C (248 °F)	146.90
      130 °C (266 °F)	150.73
      140 °C (284 °F)	154.55
      150 °C (302 °F)	158.36

      The results of the preceding procedure are in the following list:

      • The resistance is correct. The RTD is functioning normally. Proceed to 3.

      • The resistance is not correct. The RTD is not functioning normally. Replace the RTD. Stop.

3. Measure the resistance of the interconnect wiring harness.

   1. Connect the RTD to the wiring harness. This is done by connecting the connector head of the RTD.

   2. Locate the RTD terminal and locate the sense terminal. The terminals are located in the control panel. The RTD terminal is terminal 2 and the sense terminal is terminal 3.

      ReferenceSchematic, RENR2458, "3600 Diesel Generator Monitoring System Electrical System".

   3. Measure the resistance on the terminal block in the control panel. Measure the resistance between the following terminals: Terminal 2 and Terminal 3. This measures the resistance of the interconnect wiring harness.

      The results of the preceding procedure are in the following list:

      Note: A high resistance measurement indicates an open circuit. A low resistance measurement indicates a closed circuit.

      • The resistance is less than 160 ohms. The wiring is functioning normally. STOP.

      • The resistance is greater than 160 ohms. The wiring is not functioning normally. Repair the wiring. Verify that the repair resolves the problem. STOP.