While the first applications of wireless technology were limited to simply monitoring processes, now WirelessHART can be integrated into the regulating process for controlling ball valves, fans and other mechanical devices. The discrete WirelessHART I/O field device (photo) can capture digital input signals and switch digital outputs up to Zone 1. Namur sensors or mechanical switches are used to determine the direction of rotation and monitor the frequency of an engine or the fill level of a tank using limit value switches. It is also possible to intelligently monitor the position of valves by measuring the breakaway time and runtime of each opening and closing process that the valve performs. In this way, blocked valves can be detected simply by measuring time. Depending on the version of the four wireless-field devices, equipment such as valve position controllers, low-power piezo valves, motor switches, and pumps can be switched on or off via the outputs. — Pepperl+Fuchs GmbH, Mannhein, Germany
Control in the field with WirelessHART
| By Chemical Engineering