Valve positioner having bypass component and control valve comprised thereof
AssigneeDresser, Inc.
InventorSandro Esposito
Life of this patent
Estimating the term…
Abstract
A valve positioner that can maintain operation of the control valve despite failures in one or more components. The valve positioner may reduce downtime by allowing in-situ repair to occur on the valve positioner. The valve positioner may incorporate a by-pass component, which can utilize control input signals (e.g., a 4-20 mA signal) to energize one or more components (e.g., a current-to-pressure converter) to cause the control valve to modulate fluid flow without the digital microprocessor and/or related components.
Claims20
A valve positioner, comprising.
- a signal switching component having a first input, a second input, and an output, the signal switching component having a first operating state that couples the first input with the output and a second operating state that couples the second input to the output;
- a processing component coupled with one of the first input and the second input and forming an operating loop with the signal switching component,
- wherein the operating loop conducts an operating signal that instructs the signal switching component to change from the first operating state to the second operating state.
A circuit for use in a valve positioner to control operation of a valve, the circuit comprising:
- a processor;
- a switch coupled with the processor;
- and
- a current-to-pressure converter coupled to the switch,
- wherein the processor is operative to:
- receive a feedback signal having a value that defines an operating parameter for the valve, and
- generate an operating signal having a level corresponding to the value of the feedback signal,
- wherein the switch is operative to change between a first state and a second state in response to the level of the operating signal so as to conduct different input signals to the current-to-pressure converter.
A method for operating a valve positioner to position components on a valve, said method comprising:
- receiving a pair of input signals at a switch, the pair of input signals having properties to operate a current-to-pressure converter, at least one of which originates from a processor configured to maintain operation of a valve;
- and
- operating the switch in one of a first state or a second state to conduct one of the pair of input signals to the current-to-pressure converter,
- wherein one of the first state and the second state permits the processor be removed without disrupting operation of the valve.
Dependencies are inferred from the claim text.