Search results
Results From The WOW.Com Content Network
This ensures that in case of a wire break the alarm will be triggered. If the circuit were normally open, a wire failure would go undetected, while blocking actual alarm signals. Analog sensors and modulating actuators can usually be installed and wired such that the circuit failure results in an out-of-bound reading – see current loop. For ...
valve with pneumatic diaphragm actuator and "smart" positioner which will also feed back to the controller the actual valve position Pneumatic rack and pinion actuators for valve controls of water pipes. A pneumatic actuator mainly consists of a piston or a diaphragm which develops the motive power. It keeps the air in the upper portion of the ...
"Air or control signal failure to open" – On failure of compressed air to actuator, the valve opens under spring pressure or by backup power. The modes of failure operation are requirements of the failure to safety process control specification of the plant. In the case of cooling water it may be to fail open, and the case of delivering a ...
The blue valve body is visible in-line with the pipe. The valve actuator opens or closes the butterfly disc of the valve based on electrical signals sent to the actuator. Another valve actuator is visible in the background, with windows to indicate the valve position. A valve actuator is the mechanism for opening and closing a valve. Manually ...
Failure mode and effects analysis (FMEA; often written with "failure modes" in plural) is the process of reviewing as many components, assemblies, and subsystems as possible to identify potential failure modes in a system and their causes and effects. For each component, the failure modes and their resulting effects on the rest of the system ...
Modulating control valves each with 4-20mA I to P converter linked to pneumatic a valve positioner controlling a diaphragm actuator. An air-operated valve, also known as a pneumatic valve, is a type of power-operated pipe valve that uses air pressure to perform a function similar to a solenoid. As air pressure is increased, the compressed air ...
The Circuit Breaker is a design pattern commonly used in software development to improve system resilience and fault tolerance. Circuit breaker pattern can prevent cascading failures particularly in distributed systems. [1] In distributed systems, the Circuit Breaker pattern can be used to monitor service health and can detect failures dynamically.
Control valves are normally fitted with actuators and positioners. Pneumatically-actuated globe valves and diaphragm valves are widely used for control purposes in many industries, although quarter-turn types such as (modified) ball and butterfly valves are also used. Control valves can also work with hydraulic actuators (also known as ...