Strain-gage data acquisition system uses Ethernet

Micro Measurements has rolled out the System 9000 StrainSmart strain-gage data-acquisition system that accepts up to twelve strain-gage channels, each using a standard RJ-45 connector. It has four user-configurable inputs where you can connect higher-level voltages from an assortment of sensors, plus inputs for thermocouples (types J, K, T, E, N, R, S, B), or piezoelectric transducers. Each channel has a dedicated ADC, which lets the System 9000 simultaneously sample all channels, detailed the company.

The System 9000 accepts full, half, or quarter-bridge inputs of 120Ω, 350Ω and 1kΩ. Channels can be sampled at rates of 50,000, 25,000, 10,000 and 5,000 samples/s. All channels are oversampled and then digital finite-impulse response (FIR) filters reduce noise and stabilise measurements. Each bridge input can be driven with excitation voltages up to 10V and with up to 150mA.

The system communicates over Ethernet and, using a router and dynamic IP addresses, you can configure a system with up to 48 channels (36 strain gage plus 12 for other inputs). The additional four channels use optional input cards. The systems have Sync In and Sync Out connections to assure time synchronisation of measurements across two or more systems.

Each System 9000 comes with software that lets you configure measurements and capture data. At the present time, Micro Measurements does not provide a programming interface nor drivers that let you develop custom applications.

The base price of the System 9000 is at $9,600.

- Martin Rowe
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