Analog signal conditioners get strain-gage input modules

By Control Engineering Staff January 5, 2006
Measuring only 1.11 x 1.65 x 0.4 in. (28.1 x 41.9 x 10.2 mm), the 8B signal conditioner is 80% smaller than similar products, Dataforth says; signal filtering is accomplished with a 5-pole filter optimized for time and frequency response.

Dataforth Corp . adds 8B38 strain-gage input-modules with a choice of 3 Hz or 8 kHz signal bandwidth, to the SensorLex 8B family of isolated analog signal conditioners.
Modules provide excitation to strain element-based sensors, then isolate, filter, and amplify the resulting sensor output and provide high-level analog voltage output. Available models provide excitation voltage choices of 3.333 V or 10.000 V, allowing connection to sensors with nominal impedance from 100 ohm to 10 k ohm. Constant voltage sensor excitation is standard in 8B38 modules using a voltage source that is precisely regulated to minimize changes over time, temperature, and power supply voltage.

Applications include any process requiring precise measurement of strain or pressure; situations where space is at a premium; vibration analysis in machinery health and other high frequency monitoring applications, using the 8 kHz wide bandwidth option; monitoring slow varying processes, such as conveyor belt systems, and applications where rejection of high frequency noise is important, using the 3 Hz narrow bandwidth option. As 8B38 modules have a low drift over time and temperature, they do not add significant measurement error; additionally, 8B38 modules provide signal conditioning in what’s said to be the smallest package. Signal gains of 167 V/V to 500 V/V are offered, allowing the modules to connect to industry standard sensors with output sensitivities of 2 mV/V and 3 mV/V. Other ranges are available. Operation and storage temperature range is -40 to 85 °C; relative humidity range is 0-95% noncondensing. All models meet EN61000-6-4 (radiated/conducted emissions) and EN61000-6-2 (ESD/RF/EFT immunity). For operation in hazardous environments, North American Class I, Division 2, and European Group II, Category 3, approvals are pending. Prices for 8B modules start at $89.

— Edited by Mark T. Hoske, editor-in-chief, Control Engineering ,
MHoske@cfemedia.com