A Novel Scalable Digital Data Acquisition System for Industrial Condition Monitoring

This article introduces a novel data acquisition system aimed at condition monitoring (CM) of complex industrial machinery and plants. Current commercial solutions can be divided into two groups: 1) high resolution and 2) data rate rack systems or distributed systems usually at the price of lower performance. The proposed solution aims at filling this gap. It relies on a daisy-chain digital bus architecture, featuring a main node and a series of subordinate nodes, which have been designed to collect data from both analog and digital transducers. It follows that the system is highly scalable and easily reconfigurable: the number and the type of transducers, ranging from low-cost micro electromechanical systems to high quality piezoelectric sensors, can be optimized to match each specific measurement requirements, even after the installation of the system. The proposed technology supports up to 32 channels at 48 kS/s, and guarantees the perfect synchronization of all signals regardless of the transducer type and its position along the bus, allowing to perform advanced data analysis. The system performance is at first evaluated with laboratory tests, then in the scenario of CM of rolling bearing faults, demonstrating good sensitivity and coherence between different accelerometer types.