Tag: instrumentation
-
Electro-Pneumatic Valve Positioners: Function & Features
Valve positioners are motion-control devices that are made in such a way to actively compare valve stem position against the control signal, adjusting the actuator diaphragm or piston till the correct stem position is achieved, that is, in a nutshell … Read more
-
Instrument Grounding: General Guidelines
Specific attention must be paid to instrument grounding, especially where field instruments are connected to a computer or microprocessor based control system. Where cable screens are used, ground continuity of screens must be maintained throughout the installation with the … Read more
-
Function Generator: Features & Applications
Features of Function Generators A function generator is a signal source that can produce different types of waveforms as its output signal. The most common output waveforms are: sine waves, square waves and triangular waves. Furthermore, some function generators also … Read more
-
Selecting a Pressure Reducing Regulator: Key Parameters to Consider
A pressure reducing regulator is used in many industrial applications. In this article, we look at key parameters that must be established to help you make the appropriate selection of a pressure reducing regulator for your application. Fig: Spring-controlled Pressure … Read more
-
Valve Positioners: Function & Types
Basic Features of a Positioner Pneumatically operated valves depend on a positioner to take an input signal from the process controller and convert it to valve travel. In other words, a positioner is a motion control device made to actively … Read more
-
Directional Control Valves: Function & Principle of Operation
Directional control valves are used to regulate the flow rate of hydraulic fluid; they are also utilized in pneumatic systems for flow control. Directional control valve works by regulating the movement of the piston in the cylinder. It admits pressurized … Read more
-
Instrument Manifolds: Function & Types
An instrument manifold also referred to as a valve manifold includes manual valves to isolate and equalize pressure from the process to the transmitter (in this case the DP transmitter) or to isolate a gauge or absolute pressure transmitter for … Read more
-
Pneumatic System Components: Types & Functions
A pneumatic system utilizes air pressure to create mechanical motion. A basic pneumatic system consists of an intake filter that traps dirt before it enters the system, an air compressor that provides a source of compressed air, a dryer that … Read more
-
Pressure Regulators: Function & Types
The main function of any gas pressure regulator is to match the flow of gas through the regulator to the demand for gas placed upon the system while maintaining the system pressure within certain acceptable limits. Generally, regulators are simpler … Read more
-
Instrument Installation – Cabling Guidelines
Instrument installation with the associated cable installation/electrical signal and control wiring should be carried out by skilled personnel who are acquainted with the safety requirements and regulations for the plant site for that specific project. Generally instrument cabling is usually … Read more