Abstract: Calibration of a valve in a vacuum system and providing a diagnostic indication in the vacuum system using the calibration includes measuring conductance of the valve as a function of angular valve position and generating a conductance calibration map or function for use during operation of the valve. An actual angular valve position is set based on the received set point angular valve position and a difference between the measured valve conductance and a predefined metric of conductance versus angular valve position. An actual system conductance and a difference between the actual system conductance and a reference system conductance for the system are determined. The diagnostic indication of a fault in the system is generated based on the actual angular valve position of the valve and the difference between the actual system conductance and the reference system conductance for the system.

Abstract: Calibration of a valve in a vacuum system and providing a diagnostic indication in the vacuum system using the calibration includes measuring conductance of the valve as a function of angular valve position and generating a conductance calibration map or function for use during operation of the valve. An actual angular valve position is set based on the received set point angular valve position and a difference between the measured valve conductance and a predefined metric of conductance versus angular valve position. An actual system conductance and a difference between the actual system conductance and a reference system conductance for the system are determined. The diagnostic indication of a fault in the system is generated based on the actual angular valve position of the valve and the difference between the actual system conductance and the reference system conductance for the system.

Abstract: Calibration of a valve in a vacuum system and providing a diagnostic indication in the vacuum system using the calibration includes measuring conductance of the valve as a function of angular valve position and generating a conductance calibration map or function for use during operation of the valve. An actual angular valve position is set based on the received set point angular valve position and a difference between the measured valve conductance and a predefined metric of conductance versus angular valve position. An actual system conductance and a difference between the actual system conductance and a reference system conductance for the system are determined. The diagnostic indication of a fault in the system is generated based on the actual angular valve position of the valve and the difference between the actual system conductance and the reference system conductance for the system.

Abstract: Calibration of a valve in a vacuum system and providing a diagnostic indication in the vacuum system using the calibration includes measuring conductance of the valve as a function of angular valve position and generating a conductance calibration map or function for use during operation of the valve. An actual angular valve position is set based on the received set point angular valve position and a difference between the measured valve conductance and a predefined metric of conductance versus angular valve position. An actual system conductance and a difference between the actual system conductance and a reference system conductance for the system are determined. The diagnostic indication of a fault in the system is generated based on the actual angular valve position of the valve and the difference between the actual system conductance and the reference system conductance for the system.

Abstract: A tool includes a chamber, a network, a sensor, a tool controller, and a pressure controller. The network carries messages to and from devices on the network. A header portion of a message indicates a sender of the message and at least one intended recipient of the message. The sensor measures a pressure within the chamber. The sensor, tool controller, and pressure controller are on the network. The pressure controller controls the pressure within the chamber in response to measurements provided by the sensor and in response to a set point provided by the tool controller. The pressure controller processes header portions of all messages carried on the network to determine the intended recipients of each message and processes at least part of data portions of both messages intended for the pressure controller and at least some messages not intended for the pressure controller.

Abstract: A valve assembly including a body defining a passageway having a longitudinal axis, a rotatable shaft extending into the passageway, generally perpendicular to the axis of the passageway, and a flapper secured to the shaft within the passageway and movable upon rotation of the shaft between an opened position and a closed position. The flapper includes a groove in an outer circumference, and a seal is received in the groove. The seal has an outer circumference greater than the outer circumference of the flapper so the entire outer circumference of the seal contacts a wall of the passageway when the flapper is moved to the closed position. The seal also has an inner circumference greater than an inner circumference of the groove of the flapper such that an enclosed space is defined between the seal and the groove. An aperture provides fluid communication between the enclosed space and the passageway.