Macro Sensors, Pennsauken, NJ, offers the HSI/R 750 Series of hermetically sealed, loop-powered 4–20 mA LVDTs. Designed for mechanical position measurement where you can make a hard connection to a test piece, the sensors are constructed of TIG-welded SS and hermetically sealed to IP68. Measurement ranges are from 2.5–500 mm with max. linearity error of 0.25% of full range output. HSI 750 Series devices are blind-bore units terminated in a glass-sealed axial connector. The HSIR 750 Series are through-bore devices with a radially mounted connector. Units can be configured for either loop-powered, 2-wire or externally powered 3-wire sourcing output.