Offering full-scale measurement ranges from 2 to 100", Measurement Specialties has introduced an absolute linear position sensor. The cable-actuated PT420 position sensor is capable of providing high accuracy and fine resolution without perfect parallel alignment, enabling easy implementation.
The sensor provides output signals of 4-20mA (2-wire) or 0-20mA (3-wire), which offer feedback signal linearly proportional to the position of the sensor’s extension cable. The sensor is suitable for industrial automation and testing applications, such as accurately measuring the position on hydraulic cylinders found in factories and utilities, proper gate position in fresh water or wastewater distribution systems and valve opening for process-related applications.
Featuring multiple cable tension and electrical connection options, as well as large full stroke ranges, the sensors provide designers with flexibility and high accuracy. Using a potentiometer that provides an essentially infinite output resolution, the PT420 operates over a temperature range from -40 to +90°C and withstands 10g of vibration to 2,000Hz maximum. Repeatability is ±0.05% full stroke with an accuracy of ±0.15% full stroke for most ranges.
The internal signal board has a simple dip-switch setting which enables output signal direction to be reversed at any time. Users can then adjust the zero and span trimpots to ensure signal values match the beginning and end stroke points. The PT420 is encased in an IP50 NEMA 1 rated anodised aluminium housing and weighs less than 2lbs.