A device for use in monitoring operation of a system asset includes an interface for receiving sensor data representative of an operating condition of the system asset, a memory device for storing the sensor data, and a processor coupled to the interface and to the memory device. The processor is configured to create a hierarchy of sensor data within the memory device, wherein the hierarchy comprises a first tier and a second tier, store a first level of the sensor data in the first tier, and store a second level of the sensor data in the second tier.