Sensors & Transducers e-Digest, Vol. 82, Issue 8, August 2007: Product News

(ISSN 1726- 5479)

LVDT Position Transmitters Operate in Hostile Environments

Pennsauken, NJ - Macro Sensors offers the HSI/R 750 Series of hermetically sealed, loop-powered 4-20mA position transmitters for a wide range of position monitoring and feedback applications. Units are specifically designed for mechanical position measurement where a hard connection can be made to a test piece. The 4-20 mA current loop input/output of these rugged and robust devices enables easy field integration with PLCs, digital indicators, host computer-based data processing, and QC data collection systems. Units can be configured for either loop-powered, two-wire or externally powered three-wire sourcing output to address different I/O requirements in various applications.

Constructed entirely of TIG welded stainless steel and hermetically sealed against hostile environments to IEC standard IP-68, HSI/R 750 Series LVDTs can be installed in hostile environments while the loop wiring connects to remote indicators and/or controllers located in environments safe from hostile conditions. Units offer precise output with a maximum linearity error of 0.25% of full range output or better using a statistically best-fit straight line derived by the least squares method. For more precision measurement the HSI/R series is also available with +/-0.10% linearity.

Available in full ranges from 0.10 inches (2.5 mm) to 20 inches (500 mm), these ¾-inch (19mm) diameter LVDTs are available as either blind bore units (HSI 750 Series) terminated in a glass-sealed axial connector that prevents the core from passing completely through the coil assembly or in a through-bore design (HSIR 750 Series) with the connector mounted radially to facilitate easy access to either end of the LVDT’s core for better mechanical support and core guidance, as well as easier cleanout in dusty or gritty environments. The radial connector also allows a shorter installed length to the sensor compared to units of the same range with axial connectors. For position sensing that requires the opposite directional sense, HSI 750 transmitters are available with reversed output slope, which gives 20 mA when the core is first inserted, decreasing to 4 mA as the core moves inward.

HSI/R 750 Series transmitters offer the frictionless operation, high resolution, excellent repeatability, and low hysteresis associated with LVDT technology, along with the convenience and simplicity of a precalibrated 4-20 mA current loop operation. The built-in electronics operate over a wide range of loop supply voltages and resistances.

LVDT Position Transmitters

Contact:

Ed Herceg

Macro Sensors

U.S. Route 130 North, Bldg. 22, Pennsauken, NJ 08110-1541

Tel: 856-662-8000, fax: 856-317-1005

E-mail: eeh@macrosensors.com