Particulate sensor and method of operation

A particulate sensing system (10) configured to detect particulates in exhaust gas (12) from a combustion process. Particulates are detected based on electrical conductivity between a first electrode (42) and a second electrode (44). A heater element (54) is provided to heat the first electrode (42) and the second electrode (44). The first electrode (42), the second electrode (44), and the heater element (54) cooperate to form a sensor (40). The heater element (54) is operated to establish a sensor (40) temperature greater than a dew-point temperature of the exhaust gas (12) and less than a bum-off temperature of the sensor (40) to reduce thermophoretic accumulation of particulates on the sensor (40). When the exhaust temperature (52) and the sensor (40) temperature are suitable for thermophoretic accumulation and electrophoretic accumulation of particulates, a voltage is applied across the electrodes to facilitate electrophoretic accumulation of particulates, and the heater element (54) is turned off so thermophoretic accumulation occurs.