Motor operated valve analysis and testing system

摘要

A valve analysis and testing system includes various devices for measuring the operating characteristics of a valve and its operator and the corresponding imposed valve stem load, which devices are attached to the valve operator. These devices include a switch position indicating circuit for purposes of detecting the open and close positions of limit and torque switches within the valve operator; which circuit includes a coil wrapped with two independent current conducting wire elements, each wire element in series with a different switch; and one wire element being wrapped about the coil core more times than the other wire, wherein a coil output induced by current flowing through one wire element will be of different magnitude than the coil output induced by current flowing through the other wire element; and, preferably, wherein current flowing through both wire elements at the same time will have an additive effect on the coil output.