- Liquid Level Sensor (Engine Coolant) for all engines
- Optional Temperature Sensor (Engine Oil) for all engines
- Speed Sensor (Engine) for all engines
Note: On C32 controlled engines, all of the listed sensors are connected directly to the GSC+P. On C32 engines the oil pressure sensor and coolant temperature sensor are connected to the engine ECM instead of the GSC+P. The engine ECM sends the data from these two sensors to the GSC+P display. Refer to Troubleshooting, RENR9348 for information on these two sensors.
Temperature Sensor (Engine Oil)
Note: This description applies to EUI,MUI and PEEC controlled engines.
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| Illustration 1 | g00310269 |
Engine Oil Temperature Sensor | |
The engine oil temperature sensor is optional and the sensor is an input of the GSC+P. The sensor reports the engine oil temperature to the GSC+P. The GSC+P shows the engine oil temperature on the lower display. Also, the GSC+P uses the information from the sensor in order to determine when a high oil temperature alarm exists. The engine oil temperature sensor is mounted on the outside of one of the engine oil galleries. The exact location depends on the engine model.
The engine oil temperature sensor is a pulse width modulated type of sensor. The sensor continuously generates a PWM signal. The duty cycle of the PWM signal continuously varies from 10% to 95% in proportion to the oil temperature of the engine. The GSC+P receives the PWM signal and the GSC+P measures the duty cycle in order to determine the engine oil temperature. The base frequency of the signal is constant at 455 Hz (370 to 550 Hz). The signal wire of the oil temperature sensor connects to connector contact 14 of the GSC+P. The signal wire is found at connector contact "C" of the sensor. The sensor is supplied operating power (8 DCV) at connector contact "A" from the GSC+P (connector contact 9).
There are five setpoints that are related to engine oil temperature. The five setpoints are programmed into the GSC+P. The related setpoints are P003, P004, P025, P026 and P027. Refer to Systems Operation, "Engine/Generator Programming OP5-0".
Fluid Level Sensor (Engine Coolant)
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| Illustration 2 | g00311256 |
Engine Coolant Loss Sensor | |
The engine coolant loss sensor is optional and the sensor is an input of the GSC+P. The sensor reports the loss of engine coolant to the GSC+P. The GSC+P uses the information from the sensor in order to determine when a low coolant level fault exists. The engine coolant loss sensor is usually mounted near the top of the engine radiator. The exact location depends on the engine model.
The engine coolant loss sensor sends a negative battery signal to the GSC+P. "BATT-" for a normal level. Also, the engine coolant loss sensor sends +5 DCV to the GSC+P for a low level. The signal wire (connector contact "C") of the coolant loss sensor connects to connector contact 13 of the GSC+P. The sensor is supplied operating power (8 DCV) at connector contact "A" from the GSC+P (connector contact 9).
There are three setpoints that are related to the loss of engine coolant. The setpoints are programmed into the GSC+P. The related setpoints are P004, P005 and P006. Refer to Systems Operation, "Engine/Generator Programming OP5-0".
Speed Sensor (Engine)
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| Illustration 3 | g00311291 |
Engine Magnetic Speed Sensor | |
The engine magnetic speed sensor is an input of the GSC+P. The sensor tells the engine speed to the GSC+P. The GSC+P shows the engine speed on the lower display. Also, the GSC+P uses the information from the sensor for tasks such as activating an engine overspeed shutdown and terminating engine cranking and determining the oil step speed. The engine magnetic speed sensor is mounted on the flywheel housing of the engine.
The sensor creates a sine wave signal from passing ring gear teeth at the rate of one pulse per tooth. The sensor sends a sine wave signal to the GSC+P. The frequency of the signal is directly proportional to the speed of the engine. The GSC+P receives the sine wave signal and the GSC+P measures the frequency. The frequency is measured at one pulse per gear tooth in order to determine the engine speed. The wires of the sensor connect to connector contact 1 and connector contact 2 of the GSC+P within a shielded cable. The drain wire of the shielded cable is connected to the "AUX" terminal strip.
There are four setpoints that are related to the engine speed. The setpoints are programmed into the GSC+P. The related setpoints are P009, P010, P011 and P012. Refer to Systems Operation, "Engine/Generator Programming OP5-0".