Caterpillar Monitoring System
The engine is equipped with a programmable Caterpillar Monitoring System. The Electronic Control Module (ECM) monitors the operating parameters of the engine. The ECM can initiate responses if a specific engine parameter exceeds an acceptable range. Three possible responses may be available for each parameter: "WARNING", "DERATE" and "SHUTDOWN". Some of the responses are not available for some of the parameters. An ET service tool is used to perform the following activities:
- Select the available responses.
- Program the level for monitoring.
- Program delay times for each response.
The default settings for the parameters are programmed at the factory. To accommodate unique applications and sites, the parameters may be reprogrammed with an ET service tool.
The screens of the ET service tool provide guidance for the programming. The following options can be programmed "ON" or "OFF": "WARNING", "DERATE" and "SHUTDOWN".
The screens of the ET service tool also provide guidance for changing setpoints. For information on programming the Caterpillar Monitoring System, use the appropriate ET service tool and see the Service Manual, "Troubleshooting" module.
The Caterpillar Monitoring System is enabled after the engine is started. When the engine rpm exceeds 50 rpm below low idle, the ECM begins checking parameters. The ECM monitors the parameters in order to determine if the parameters exceed the setpoints.
If the monitoring system initiates a warning, a deration, or a shutdown, the event is logged into the ECM. This occurs even if the parameter is programmed "OFF". If a setpoint for a parameter is exceeded, the event will be logged.
Any failure of a sensor will result in disabling the corresponding portion of the monitoring system. The failure of a sensor will cause an "ACTIVE" diagnostic code for the sensor.
The derating is cumulative. For example, a derating of five percent followed by a derating of two percent results in a total derating of seven percent. If the conditions that cause the derating are not corrected, the derating will continue.
Default Settings for the Caterpillar Monitoring System
Derate - This is a reduction of engine horsepower in response to an abnormal operating condition.
Setpoint - This is a specific value which can activate the following responses: warning, deration and shutdown. The setpoint can be a pressure, a speed, a temperature, or a voltage.
Hysteresis - This is the change in the signal from a sensor that is tolerated by the ECM. This is the difference between the setpoint that activates a response and the value that deactivates the response. For example, a warning for low voltage can activate if a value below 20 volts is detected by the ECM. The voltage must rise to 22 volts in order to clear the warning. The hysteresis is the 2 volts that are above the 20 volts.
Voltage
The ECM automatically warns the operator of low system voltage. The default settings that are programmed at the factory are listed in Table 1.
| Voltage Monitoring | |
| Parameter | Default Setting |
| Warning setpoint | 20 volts |
| Warning delay | 10 seconds |
| Hysteresis | 2 volts |
| Security level | No required password |
If the voltage is below 20 volts for 10 seconds, a warning will occur. To deactivate the warning, the voltage must rise above 22 volts.
The setpoint can be programmed to a value between 20 and 22 volts.
Engine Oil Pressure
The ECM automatically performs the following functions for low engine oil pressure:
- Warning
- Shutdown
The strategy is based on a map of the engine oil pressure versus the engine rpm. For engines that are rated up to 1300 rpm, see Illustration 1. For engines that are rated at 1301 rpm and above, see Illustration 2. The default settings that are programmed at the factory are listed in Table 2.
| Engine Oil Pressure | |
| Parameter | Default Settings |
| Upper oil pressure limit | 175 kPa (25 psi) |
| Lower oil pressure limit | 41 kPa (5.9 psi) |
| High engine speed limit | 1250 |
| Low engine speed limit | 452 |
| Hysteresis | 40 kPa (5.8 psi) |
| Activation delay | 10 seconds |
| Security level | Required password |
| Warning setpoint | Map |
| Warning delay | 4 seconds |
| Shutdown setpoint | Map |
| Shutdown delay | 9 seconds |
 | |
| Illustration 1 | g00570830 |
Map of the engine oil pressure versus the engine rpm for engines that are rated up to 1300 rpm (Y) Engine oil pressure in kPa (X) Engine rpm (1) Hysteresis (2) Minimum engine oil pressure | |
 | |
| Illustration 2 | g00592294 |
Map of the engine oil pressure versus the engine rpm for engines that are rated at 1301 rpm and above (Y) Engine oil pressure in kPa (X) Engine rpm (1) Hysteresis (2) Minimum engine oil pressure | |
If the engine oil pressure is below the minimum pressure for four seconds, a warning will occur. To deactivate the warning, the engine oil pressure must rise above the hysteresis that is set in the map.
If the engine oil pressure is below the minimum pressure for nine seconds, a shutdown will occur.
The map cannot be reprogrammed.
High Coolant Temperature
The ECM will automatically perform the following functions for high coolant temperature:
- Warning
- Derating
- Shutdown
The default settings that are programmed at the factory are listed in Table 3.
| High Coolant Temperature | |
| Parameter | Default Setting |
| Warning setpoint | 102 °C (216 °F) |
| Warning delay | 5 seconds |
| Derate setpoint | 107 °C (225 °F) |
| Derate delay | 30 seconds |
| Maximum time of derating | 480 seconds |
| Hysteresis | 5 °C (9 °F) |
| Security level | Password required |
| Maximum derating | 25% |
| Shutdown setpoint | 107 °C (225 °F) |
| Shutdown delay | 5 seconds |
If the coolant temperature is above 102 °C (216 °F) for five seconds, a warning will occur. The coolant temperature must be below 97 °C (207 °F) in order to deactivate the warning.
If the coolant temperature is above 107 °C (225 °F) for 30 seconds, a derating will occur. A continuous 25 percent derating is reached in 480 seconds. When the coolant temperature is less than 102 °C (216 °F), the percent of the derating decreases. The percent of the derating decreases until the capability of providing full power is restored. However, if the coolant temperature rises above the setpoint again, the derating will resume.
If the coolant temperature is above 107 °C (225 °F) for five seconds, a shutdown will occur.
Note: The default setting for the delay of the derating is programmed to the maximum value of 30 seconds. The delay for the shutdown is five seconds. These settings result in a shutdown that occurs before a derating. These settings are programmed because most customers prefer a shutdown for high coolant temperature. The settings can be programmed to different values.
The setpoint can be programmed in the range of 90 to 102 °C (194 to 215 °F).
Low Coolant Temperature
The ECM will automatically warn the operator of low coolant temperature. The default settings that are programmed at the factory are listed in Table 4.
| Low Coolant Temperature | |
| Parameter | Default Setting |
| Warning setpoint | 80 °C (176 °F) |
| Warning delay | 5 seconds |
| Activation delay | 10 minutes |
| Hysteresis | 5 °C (9 °F) |
| Security level | Password required |
To activate this strategy, the engine must operate for a minimum of ten minutes at an average load of 20 percent or more. If the average load is 20 percent or more and the coolant temperature is below 80 °C (176 °F) for five seconds, a warning will occur. To deactivate the warning, one of the following conditions must occur:
- The average load for ten minutes must decrease to less than 20 percent.
- The coolant temperature must rise above 85 °C (185 °F).
The setpoint can be programmed in the range of 63 to 85 °C (145 to 185 °F).
Note: The low coolant temperature is monitored in order to detect a failure of the water temperature regulators. This feature is not intended to monitor the operation of jacket water heaters.
Overspeed
The ECM will automatically perform the following functions if an engine overspeed occurs:
- Warning
- Shutdown
Different setpoints are based on the engine application and the engine rating. The default settings that are programmed at the factory are listed in Table 5.
| Overspeed | |
| Parameter | Default Setting |
| Warning setpoint | 1.18 times the rated rpm |
| Warning delay | 0 seconds |
| Shutdown setpoint | 1.18 times the rated rpm |
| Shutdown delay | 0 seconds |
| Hysteresis | 100 rpm |
| Security level | Required password |
If the engine speed exceeds the setpoint rpm, a warning and a shutdown will occur. The fuel will be shut off and the air shutoff (if equipped) will be activated.
| NOTICE |
|---|
Failure to reset air shutoffs prior to restart may result in severe engine damage. |
The air shutoff must be reset before the engine is restarted. Ensure that both of the air shutoffs are reset.
Note: The default settings for the warning and for the shutdown are equal. Therefore, the warning and the shutdown occur simultaneously. These settings were selected in order to log both a warning and a shutdown: furthermore, an overspeed condition can occur rapidly.
The setpoints can be programmed to a value between 1200 and 2400 rpm.
Inlet Air Restriction
The ECM will automatically perform the following functions if a high inlet air restriction occurs:
- Warning
- Derating
The strategy is applied to the right side air filter and/or the left side air filter. The default settings that are programmed at the factory are listed in Table 6.
| Inlet Air Restriction | |
| Parameter | Default Setting |
| Warning setpoint | 7 kPa (1 psi) |
| Warning delay | 5 seconds |
| Derate setpoint | 7 kPa (1 psi) |
| Derate delay | 5 seconds |
| Security level | Password required |
| Derating per 1 kPa (.15 psi) |
2% |
| Maximum restriction | 25 kPa (3.6 psi) |
If the inlet air restriction is above 7 kPa (1 psi) for five seconds, both a warning and a derating will occur. The continuous schedule of the derating is two percent per 1 kPa (0.15 psi). The maximum derating is 50 percent at 25 kPa (3.6 psi).
The derating remains at the maximum level until the situation is corrected. To reset the derating to zero percent, remove power from the ECM. The ECM will reset when power is returned.
Altitude
The ECM automatically compensates for engine operation at higher elevations. The ECM derates the fuel delivery according to the barometric pressure. The barometric pressure is sensed by the atmospheric pressure sensor. The atmospheric pressure has an effect on the performance of the engine. Derating the fuel delivery maintains the temperatures of the exhaust gas within acceptable limits.
The derating of the engine starts at a specific barometric pressure. The barometric pressure is equal to the atmospheric pressure of an elevation. The atmospheric pressure is specific for the engine and for the engine rating. The default settings that are programmed at the factory are listed in Table 7.
| Altitude | |
| Parameter | Default Setting |
| Derate setpoint | 2T specification |
| Security level | Required password |
| Derating per 305 m (1000 ft) |
3% |
| Maximum derating | 35% of the rated power |
If the barometric pressure is below the setpoint, a warning and a derating will occur. The continuous schedule of the derating is three percent per 1 kPa (.15 psi) of pressure below the setpoint. The maximum derating is 35 percent.
Exhaust Temperature
The ECM will automatically perform the following functions if a high exhaust temperature occurs:
- Warning
- Derating
The strategy is applied to the right side exhaust manifold and/or the left side exhaust manifold. The default settings that are programmed at the factory are listed in Table 8.
| Exhaust Temperature | |
| Parameter | Default Setting |
| Warning setpoint | 2T specification |
| Warning delay | 5 seconds |
| Derate setpoint | 2T specification |
| Derate delay | 5 seconds |
| Delay per step | 15 seconds |
| Hysteresis | 10 °C (18 °F) |
| Security level | Required password |
| Derating per step | 2% per step |
If the exhaust temperature is above the setpoint for the warning for five seconds, a warning will occur.
If the exhaust temperature is above the setpoint for the derating for five seconds, the derating will occur.
The derating reduces the power by two percent. This is followed by a 15 second delay. If the exhaust temperature is not reduced below the setpoint after the 15 second delay, the engine is derated another two percent.
When the exhaust temperature is reduced to less than the setpoint, two percent of the power is restored for every 15 seconds. This continues until full power is restored. However, if the exhaust temperature rises above the setpoint again, the derating resumes.
Oil Filter Differential Pressure
The ECM automatically warns the operator of high oil filter differential pressure. The default settings that are programmed at the factory are listed in Table 8.
| Oil Filter Differential Pressure | |
| Parameter | Default Setting |
| Warning setpoint | 105 kPa (15 psi) |
| Warning delay | 5 seconds |
| Hysteresis | 10 kPa (1.5 psi) |
| Security level | No required password |
If the oil filter differential pressure is above 105 kPa (15 psi) for five seconds, a warning will occur. To deactivate the warning, the oil filter differential pressure must be below 95 kPa (13.5 psi).
Fuel Filter Differential Pressure
The ECM automatically warns the operator of high fuel filter differential pressure. The default settings that are programmed at the factory are listed in Table 10.
| Fuel Filter Differential Pressure | |
| Parameter | Default Setting |
| Warning setpoint | 105 kPa (15 psi) |
| Warning delay | 5 seconds |
| Hysteresis | 10 kPa (1.5 psi) |
| Security level | No required password |
If the fuel filter differential pressure is above 70 kPa (10 psi) for five seconds, a warning will occur. To deactivate the warning, the fuel filter differential pressure must be below 60 kPa (8.7 psi).
Crankcase Pressure
The ECM will automatically perform the following functions if high crankcase pressure occurs:
- Warning
- Derating
- Shut down
The default settings that are programmed at the factory are listed in Table 11.
| Crankcase Pressure | |
| Parameter | Default Setting |
| Warning setpoint | 2 kPa (.3 psi) |
| Warning delay | 3 seconds |
| Derate setpoint | 6 kPa (.9 psi) |
| Derate delay | 10 seconds |
| Maximum time of derating | 480 seconds |
| Hysteresis | 0.25 kPa (.036 psi) |
| Security level | Required password |
| Maximum derating | 25% |
| Shutdown setpoint | 3.5 kPa (.51 psi) |
| Shutdown delay | 3 seconds |
If the crankcase pressure is above 2 kPa (.3 psi) for three seconds, a warning will occur. To deactivate the warning, the crankcase pressure must be below 1.75 kPa (.254 psi).
If the crankcase pressure is above 6 kPa (.9 psi) for 10 seconds, a derating will occur. The continuous schedule of the derating will reach 15 percent in 480 seconds.
When the crankcase pressure is less than 5.75 kPa (.39 psi), the percent of the derating is decreased until full power is restored. However, if the crankcase pressure rises above the setpoint again, the derating resumes.
If the crankcase pressure is above 3.5 kPa (.51 psi) for three seconds, a shutdown will occur.
Note: The default settings result in a shutdown that occurs before a derating. These settings were selected for the reason that high crankcase pressure can occur rapidly. The settings can be reprogrammed.
Aftercooler Coolant Temperature
Note: The following information concerns engines with separate circuit aftercooling. For engines with jacket water aftercooling, monitoring of the aftercooler coolant temperature is disabled. However, the jacket water coolant temperature is monitored for all engines.
The ECM will automatically perform the following functions when high aftercooler coolant temperature occurs:
- Warning
- Derating
- Shut down
The default settings that are programmed at the factory are listed in Table 12.
| Aftercooler Coolant Temperature | |
| Parameter | Default Setting |
| Generator set warning setpoint | 102 °C (215 °F) |
| Marine auxiliary warning setpoint | 50 °C (122 °F) |
| Warning delay | 5 seconds |
| Derate setpoint | 107 °C (225 °F) |
| Derate delay | 5 seconds |
| Maximum time of derating | 480 seconds |
| Hysteresis | 3 °C (5.4 °F) |
| Security level | Password required |
| Maximum derating | 25% |
| Shutdown setpoint | 107 °C (225 °F) |
| Shutdown delay | 5 seconds |
If the aftercooler coolant temperature is above 102 °C (215 °F) for five seconds, a warning will occur. To deactivate the warning, the aftercooler coolant temperature must be below 99 °C (210 °F).
If the aftercooler coolant temperature is above 107 °C (225 °F) for five seconds, a derating will occur. The continuous schedule of the derating will reach 25 percent in 480 seconds.
When the aftercooler coolant temperature is less than 104 °C (220 °F), the percent of the derating is decreased until full power is restored. However, if the aftercooler coolant temperature rises above the setpoint again, the derating resumes.
If the aftercooler coolant temperature is above 107 °C (225 °F) for five seconds, a shutdown will occur.