A method of detecting electrical failure in a refrigeration system is provided. The method includes determining whether a present superheat of the refrigeration system is between a maximum superheat and a minimum superheat for the refrigeration system, the maximum superheat and the minimum superheat defining a normal operating range. The method also includes detecting an electrical property of an expansion valve assembly of the refrigeration system responsive to the superheat being outside the normal operating range. The method further includes determining whether the expansion valve assembly as experienced an electrical failure based on at least the electrical property. A signal indicating that the expansion valve has experienced an electrical failure is generated based on a determination that the expansion valve assembly has experienced the electrical failure.

A method of detecting electrical failure in a refrigeration system is provided. The method includes determining whether a present superheat of the refrigeration system is between a maximum superheat and a minimum superheat for the refrigeration system, the maximum superheat and the minimum superheat defining a normal operating range. The method also includes detecting an electrical property of an expansion valve assembly of the refrigeration system responsive to the superheat being outside the normal operating range. The method further includes determining whether the expansion valve assembly as experienced an electrical failure based on at least the electrical property. A signal indicating that the expansion valve has experienced an electrical failure is generated based on a determination that the expansion valve assembly has experienced the electrical failure.

An apparatus is provided to test valves. The apparatus includes a sensor and a driving mechanism. The driving mechanism is configured to control an external camshaft that is coupled to a valve train of an engine head. The apparatus controls the driving mechanism to control a rotation of the external camshaft that further controls an activation of each valve of the valve train associated with the engine head. The apparatus further controls the sensor to acquire information associated with the activation of each valve of the valve train based on the rotation of the external camshaft. The apparatus further compares the acquired information with pre-stored information, to determine an abnormality in each valve of the valve train, and generates a notification based on the comparison.

A method of using a computer processor for grouping prosthetic valve leaflets of an aggregate of prosthetic valve leaflets is provided. For each leaflet of the aggregate, in response to an image parameter of the leaflet, a leaflet-flexibility value is derived. At least some of the leaflets of the aggregate are designated into leaflet groups, based on similarity between the respective leaflet-flexibility value of each leaflet of the aggregate. For each of the designated leaflet groups, the flexibility value of each leaflet in the designated leaflet group is within the intra-group tolerance with respect to the leaflet-flexibility value of each other leaflet in the designated leaflet group. An indication of the designated leaflet groups is outputted. Other embodiments are also described.

Automatic testing for control valves is provided for diagnosing of actuators, including actuators not equipped with analog or discrete position transmitters. A valve controller confirms steady-state conditions for a turbo-compressor system that includes a control valve in a first position and sends, to an actuator for the control valve, a signal to initiate a partial valve stroke to move the control valve away from the first position. The valve controller receives feedback signals from sensors in the turbo-compressor system and monitors the feedback signals for a change from the steady-state conditions. When the monitoring detects a change from the steady-state conditions within a defined time period, the valve controller sends, to the actuator, a signal to return the control valve to the first position. When the monitoring does not detect a change from the steady-state conditions within the defined time period, the valve controller generates an alarm signal.

Automatic testing for control valves is provided for diagnosing of actuators, including actuators not equipped with analog or discrete position transmitters. A valve controller confirms steady-state conditions for a turbo-compressor system that includes a control valve in a first position and sends, to an actuator for the control valve, a signal to initiate a partial valve stroke to move the control valve away from the first position. The valve controller receives feedback signals from sensors in the turbo-compressor system and monitors the feedback signals for a change from the steady-state conditions. When the monitoring detects a change from the steady-state conditions within a defined time period, the valve controller sends, to the actuator, a signal to return the control valve to the first position. When the monitoring does not detect a change from the steady-state conditions within the defined time period, the valve controller generates an alarm signal.

Described techniques provide direct measurement of shaft torque in control valve assemblies. The measured torque can be utilized to analyze the performance or health of the control valve. The described techniques utilize a direct measurement of shaft torque, providing a more accurate and precise measurement than an indirect or proxy measurement.

An apparatus is provided to test valves. The apparatus includes a base and an actuation mechanism with an actuator having a first end coupled to the base and a second end retractably extends from the base. The apparatus further includes a common platform with a first surface and a second surface. The first surface coupled to the second end of the actuator and moves from the base, based on an extension of the actuator. The apparatus further includes a plurality of engagement members each of which includes a first portion coupled to the first surface and a second portion coupled to the second surface. The apparatus further includes a plurality of sensors coupled to the plurality of engagement members such that each sensor of the plurality of sensors is coupled to corresponding member of the plurality of engagement members and coupled with a valve associated with a machine.

A testing device characterizes a damper/valve in situ in a HVAC system. It comprises a controller including a processor and a memory and circuitry. The testing device is mounted on a damper assembly having a control shaft and a damper rotatably coupled to the control shaft such that the control shaft is activated by the circuitry of the testing device. The testing device further comprises computer-readable logic code to: open and close the damper by actuating the control shaft, detect a rotational position of the damper and a torque required to move the damper to the rotational position, characterize a plurality of torques required to drive the damper to a plurality of pre-determined rotational positions of the damper when subjected to a fluid flow to generate damper rotational position data vs. torque data, and store the damper rotational position data vs. torque data to produce damper characteristic graphs.

A testing device characterizes a damper/valve in situ in a HVAC system. It comprises a controller including a processor and a memory and circuitry. The testing device is mounted on a damper assembly having a control shaft and a damper rotatably coupled to the control shaft such that the control shaft is activated by the circuitry of the testing device. The testing device further comprises computer-readable logic code to: open and close the damper by actuating the control shaft, detect a rotational position of the damper and a torque required to move the damper to the rotational position, characterize a plurality of torques required to drive the damper to a plurality of pre-determined rotational positions of the damper when subjected to a fluid flow to generate damper rotational position data vs. torque data, and store the damper rotational position data vs. torque data to produce damper characteristic graphs.