Abstract: 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.

Abstract: 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 provide for statically calibrating the operator relative to the imposed valve load and provide recording traces of the imposed load and associated parameters during dynamic conditions as related to the operation of the operator and valve combined. The System provides initial dynamic traces after initial assembly, maintenance and/or periodic testing of the operator and valve. The System is then used to provide diagnostic dynamic traces at any specified time in the future for the operator and valve. These further traces are used to compare with earlier traces to verify correct performance and most importantly to detect induced or impending damage, malfunctions, or maintenance requirements for the operator and valve.

Abstract: 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 provide for statically calibrating the operator relative to the imposed valve load and provide recording traces of the imposed load and associated parameters during dynamic conditions as related to the operation of the operator and valve combined. The system provides initial dynamic traces after initial assembly, maintenance and/or periodic testing of the operator and valve. The system is then used to provide diagnostic dynamic traces at any specified time in the future for the operator and valve. These future traces are used to compare with earlier traces to verify correct performance and most importantly to detect induced or impending damage, malfunctions, or maintenance requirements for the operator and valve.

Abstract: A means of measuring the operating characteristics of a valve and its operator (16) and the corresponding imposed valve stem load is attached to the valve operator. The device provides a means of statically calibrating the operator relative to the imposed valve load and provides the means for recording traces of the imposed load and associated parameters and during dynamic conditions as related to the operation of the operator and valve combined. The device provides initial dynamic traces after initial assembly, maintenance and/or periodic testing of the operator and valve. The device is then used to provide diagnostic dynamic traces at any specified time in the future for the operator and valve. These future traces are used to compare with earlier traces to verify correct performance and most importantly to detect induced or impending damage, malfunctions, or maintenance requirements for the operator and valve.