THE DEVELOPMENT OF IN-SITU ELECTROCHEMICAL OIL-CONDITION SENSORS

The useful life of an engine oil may vary considerably; therefore, an on-board sensor would be helpful in monitoring the oil's condition con tinuously. In this work, in situ macro and micro oil-condition sensors have been developed and tested in two sets of engine-oil samples. It is found that after suppressing the high output current associated wit h fresh engine oil, the microsensor's output correlates with the total acid number (TAN) of engine oil. Because an oil's TAN will increase w ith use, this microsensor has the potential to detect the end of usefu l oil life and signal the need for an oil change.