loop diagram

Document Type Information
Details and background about this document type.
Description
A diagram showing details all elements of a control loop, from sensing element through to controlling element, and cabling and wiring details for the associated instruments. Includes junction box, marshalling cabinet and control panel terminations and power supply details.
Synonyms
  • CFIHOS ID
    CFIHOS-70000205
Equipment
Equipment that requires this document type.

An analyser intended to determine the relation between the boiling temperatures and the fraction distilled. It includes the initial boiling point and the final boiling point.

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A 'detector' for measuring the velocity, mass, charge, flight direction, and number of dust particles in space.

A detector intended to detect a leakage current to earth.

A control valve that uses a rotating disc as closing element, and with a design that causes the disc to take a slightly eccentric path during actuation.

An actuator that produces a specified movement when excited by an electric signal.

An element located in a flowstream measuring the flow using electro-magnetic forces.

A flow transmitter that is specially designed to convert the signals from an electromagnetic flow meter into a standardized electrical output signal.

A physical object that comprises a printed circuit board with electronic components intended for receive, process/transform and transmit electrical signals.

A controller that uses in-built algorithms executed by electronic circuitry to perform its function.

A valve that is assigned to act in case of emergency.

A detector that is intended to sense a flame.

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A specially designed switch with connections for inputs from multiple flame detectors. The switch has a built in logic to determine the presence of a flame based on these inputs.

An analysing instrument intended to determine the flash point of a substance.

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A detecting element that is producing a signal that is proportional to a flow rate.

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A gauge intended to indicate a liquid or gas flow.

A regulator that normally use the differential pressure principle across an orifice to control the valve trim and regulate flow.

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A functional switch that is intended to give a signal when the flow have reached a pre-set value.

A totalizer that adds up flow measurements.

A flow transmitter providing an output signal that is proportional to the flow inputs from a flow element.

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A device capable of detecting droplets of water vapour suspended in the air near the ground.

An analyser intended to determine the freezing point of a liquid.

A device that generates an electrical signal of a specified frequency.

A signal converter that is intended to convert a frequency or rotational speed input signal into a 0 - 20 mA or 4 - 20 mA current output signal.

A chromatograph where gas is injected directly into one or more separation columns.

An analyser which analyses the composition of gaseous mixture with two or more components.

Registers
Registers where this document type is included.
A collection of all instrument set points and/or alarms. Each instrument having an alarm or trip function is listed. Alarms and settings are given as percentages of transmitter range and in engineering units, together with transmitter range, location of the annunciation point, cabinet, identification and relevant P&IDs/PEFS or logic drawing.
An authoritative collection of values with a relationship to instrumentation. The columns of this collection is specified and controlled.