Instrumentation

Instrumentation is the branch of science that deals with measurement and control in order to increase efficiency and safety in the workplace.

An instrument is a device placed in the field, or in the control room, to measure or manipulate flow, temperature, pressure and other variables in a process. Instruments include but are not limited to valves, transmitters, transducers, flame detectors and analyzers. Instruments send either pneumatic or electronic signals to controllers which manipulate final control elements (a valve) in order to get the process to a set point, usually decided by an operator.

Control instrumentation includes devices such as solenoids, Electrically Operated Valves,
breakers, relays, etc. These devices are able to change a field parameter, and provide remote control capabilities.

Transmitters are devices which produce an analog signal, usually in the form of a 4-20 mA electrical current signal, although many other options are possible using voltage, frequency, or pressure. This signal can be used to directly control other instruments, or sent to a PLC, DCS, SCADA system or other type of computerized controller, where it can be interpreted into readable values, or used to control other devices and processes in the system.

Instrumentation plays a significant role in both gathering information from the field and changing thefield parameters, and as such are a key part of control loops.

Measurement

Instrumentation can be used to measure certain field parameters (physical values):

These measured values include:
*pressure, either differential or static
*flow
*temperature
*level
*density
*viscosity
*radiation
*current
*voltage
*inductance
*capacitance
*frequency
*resistivity
*conductivity
*chemical composition
*chemical properties
*various physical properties
*force applied by a liquid

Control

In addition to measuring field parameters, instrumentation is also responsible for providing the ability to modify some field parameters.

Some examples include:

Instrumentation engineering

Instrumentation engineering is the engineering specialization focused on the principle and operation of measuring instruments which are used in design and configuration of automated systems in electrical, pneumatic domains etc.They typically work for industries with automated processes, such as chemical or manufacturing plants, with the goal of improving system productivity, reliability, safety, optimization and stability.To control the parameters in a process or in a particular system Microprocessors , Micro controllers ,PLC's etc are used. But their ultimate aim is to control the parameters of a system.

Instrumentation technologists and mechanics

Instrumentation technologists, technicians and mechanics specialize in troubleshooting and repairing instruments and instrumentation systems. This trade is so intertwined with electricians, pipefitters, power engineers, and engineering companies, that one can find him/herself in extremely diverse working situations. An over-arching term, "Instrument Fitter" is often used to describe people in this field, regardless of any specialisation.

ee also

* Metrology
* Measuring instrument

External links

* [http://www.isa.org Instrumentation Society of America] , see Instrument Society of America for more information.
* [http://www.engineersedge.com/instrumentation/instrumentation_table_content.htm Instrumentation and Control Devices - Engineers Edge]
* [http://openticle.com/instrumentation-and-control/ Instrumentation and Control] Free Online Article
* [http://www.pacontrol.com/index.html Free online pdf stuff]
* [http://www.hss.energy.gov/NuclearSafety/techstds/standard/hdbk1013/h1013v1.pdf Instrumentation & control Handbook] (pdf)