- Pressure Sensor (Engine Oil) for MUI and PEEC engines
- Temperature Sensor (Engine Coolant) for MUI and PEEC engines
- Liquid Level Sensor (Engine Coolant) for all engines
- Temperature Sensor (Engine Oil) for all engines
- Speed Sensor (Engine) for all engines
Note: On MUI engines and PEEC engines, all of the listed sensors are connected directly to the GSC+. The oil pressure sensor and the coolant temperature sensor are connected to the engine ECM on EUI engines. The sensors are not connected to the GSC+. The engine ECM sends the data from the two sensors to the GSC+. The data is sent to the GSC+ for display. Refer to Troubleshooting, RENR2227, "3406E and 3456 Generator Set Engines"for information on these two sensors.
Pressure Sensor (Engine Oil)
Note: MUI engines and PEEC engines
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| Illustration 1 | g00311286 |
Engine Oil Pressure Sensor | |
The engine oil pressure sensor is an input of the GSC+. The sensor tells the GSC+ the current engine oil pressure. The GSC+ shows the engine oil pressure on the lower display and the GSC+ also uses the sensor information to determine when a low engine oil pressure fault exists. The engine oil pressure sensor is mounted on the outside of one of the engine oil galleries. The engine model determines the exact location of the engine oil pressure sensor.
The engine oil pressure sensor is a pulse width modulated sensor. This sensor continuously generates a PWM signal. The duty cycle of the PWM signal varies from 10 to 90%. The duty cycle varies proportionally to the oil pressure of the engine. The GSC+ receives the PWM signal. The GSC+ measures the duty cycle in order to determine the oil pressure of the engine. The base frequency of the signal is constant at 500 ± 150 Hz. The signal wire of the oil pressure sensor connects to connector contact 8 of the GSC+. The signal wire of the oil pressure sensor is found on connector contact "C". The sensor is supplied operating power (8 DCV) at connector contact "A" from the GSC+ (connector contact 9).
There are five setpoints that are related to engine oil pressure. The setpoints that are programmed into the GSC+ are P003, P004, P012, P013 and P014. See Systems Operation, "Engine Generator Programming OP5-0".
Temperature Sensor (Engine Coolant)
Note: MUI engines and PEEC engines
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| Illustration 2 | g00310269 |
Engine Coolant Temperature Sensor | |
The engine coolant temperature sensor is an input of the GSC+. The engine coolant temperature sensor tells the GSC+ the engine coolant temperature. The GSC+ shows the engine coolant temperature on the lower display. Also, the GSC+ uses the information from the sensor in order to determine when a high coolant temperature fault exists or a low coolant temperature fault exists. The engine coolant temperature sensor is mounted in the water jacket. The sensor is usually mounted toward the front of the engine. The exact location depends on the engine model.
The engine coolant temperature sensor is a pulse width modulated sensor (PWM). This sensor continuously generates a PWM signal. The duty cycle of the signal varies from 10 to 95% in proportion to the coolant temperature of the engine. The GSC+ receives the PWM signal and the GSC+ measures the duty cycle in order to determine the coolant temperature of the engine. The base frequency of the signal is constant at 455 Hz (370 to 550 Hz). The signal wire of the coolant temperature sensor connects to connector contact 7 of the GSC+. The signal wire is found at connector contact "C" of the sensor. The sensor is supplied operating power (8 DCV) at connector contact "A". The operating power comes from connector contact 9 of the GSC+.
There are four setpoints that are related to the engine coolant temperature. These setpoints are programmed into the GSC+. The related setpoints are P003, P004, P015 and P016. See Systems Operation, "Engine/Generator Programming OP5-0".
Temperature Sensor (Engine Oil)
Note: EUI engines, MUI engines and PEEC engines
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| Illustration 3 | g00310269 |
Engine Oil Temperature Sensor | |
The engine oil temperature sensor is optional and the sensor is an input of the GSC+. The sensor reports the engine oil temperature to the GSC+. The GSC+ shows the engine oil temperature on the lower display. Also, the GSC+ 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+ receives the PWM signal and the GSC+ 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+. 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+ (connector contact 9).
There are five setpoints that are related to engine oil temperature. The five setpoints are programmed into the GSC+. The related setpoints are P003, P004, P025, P026 and P027. See Systems Operation, "Engine/Generator Programming OP5-0".
Fluid Level Sensor (Engine Coolant)
Note: EUI engines, MUI engines and PEEC engines
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| Illustration 4 | g00311256 |
Engine Coolant Loss Sensor | |
The engine coolant loss sensor is optional and the sensor is an input of the GSC+. The sensor reports the loss of engine coolant to the GSC+. The GSC+ 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+. "B-" for a normal level. Also, the engine coolant loss sensor sends +5 DCV to the GSC+ for a low level. The signal wire (connector contact "C") of the coolant loss sensor connects to connector contact 13 of the GSC+. The sensor is supplied operating power (8 DCV) at connector contact "A" from the GSC+ (connector contact 9).
There are three setpoints that are related to the loss of engine coolant. The setpoints are programmed into the GSC+. The related setpoints are P004, P005 and P006. See Systems Operation, "Engine/Generator Programming OP5-0".
Speed Sensor (Engine)
Note: EUI engines, MUI engines and PEEC engines
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| Illustration 5 | g00311291 |
Engine Magnetic Speed Sensor | |
The engine magnetic speed sensor is an input of the GSC+. The sensor tells the engine speed to the GSC+. The GSC+ shows the engine speed on the lower display. Also, the GSC+ 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+. The frequency of the signal is directly proportional to the speed of the engine. The GSC+ receives the sine wave signal and the GSC+ 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+ within a shielded cable. The drain wire of the shielded cable is connected to the "GND2" terminal strip for 3412 and 3456 engines.
There are four setpoints that are related to the engine speed. The setpoints are programmed into the GSC+. The related setpoints are P009, P010, P011 and P012. See Systems Operation, "Engine/Generator Programming OP5-0".