An apparatus for detecting wear particles in a fluid includes an inlet channel and an outlet channel. An ultrasonic transducer creating an acoustic wave that defines an acoustic focal zone is located between the inlet and outlet channels. A flow path located between the inlet and outlet channel is shaped to restrict the flow of the fluid to be within the acoustic focal zone. An inductive pulse sensorincludes a plurality of flow channels receiving the fluid and a plurality of planar coils wound around the flow channels. The inductive pulse sensor includes adetection system for the detection of wear particles passing through the flow channels based on a change in an electrical property of the planar coils. A single combined excitation signal is sent to all the planar coils at once and the detection system measures one single output measurement for the plurality of flow channels.