Wireless system and method for measuring an operative condition of a machine

A system comprising:

• a sensor sized to be disposed within a reservoir of a machine having moving parts that are lubricated by a liquid in the reservoir, the sensor configured to obtain a measurement of the liquid that is representative of at least one of a quantity or quality of the liquid in the reservoir;
• and
• a device body operably coupled to the sensor, the device body including a processing unit and a transmitter, the processing unit configured to communicate a query to the sensor requesting the sensor to obtain the measurement of the liquid responsive to receiving an interrogation signal from a remote reader, the processing unit further configured to generate a data signal representative of the measurement of the liquid obtained by the sensor, the transmitter configured to wirelessly communicate the data signal to the remote reader.