Glossary.
Reference definitions for the terms used across Tagsight, P&IDs, ISA 5.1, and controls engineering. Each entry is a single-paragraph definition with a link to related documents and use cases.
A
- AI, AO, DI, DO, I/O Signal TypesAI, AO, DI, and DO are the four I/O signal types every field device maps to. AI, analog input is a continuous measurement coming in, such as 4-20 mA from a tran.
- Alarm ManagementAlarm management is the discipline of designing, deploying, and maintaining the alarm system in a process plant so that operators receive only the alarms they n.
- API 610, Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas IndustriesAPI 610 is the American Petroleum Institute standard governing centrifugal pumps in petroleum, petrochemical, and natural gas service. It defines pump types by.
- API 682, Pumps, Shaft Sealing SystemsAPI 682 is the American Petroleum Institute standard governing shaft sealing systems for centrifugal and rotary pumps in petroleum, petrochemical, and natural g.
- As-built drawingAn as-built drawing is the revision of a drawing updated to reflect what was actually constructed and installed in the field, incorporating the redline markups.
- ASHRAE 62.1, Ventilation and Acceptable Indoor Air QualityASHRAE 62.1 is the American Society of Heating, Refrigerating and Air-Conditioning Engineers standard governing ventilation rates and indoor air quality in comm.
- ASME B31.3, Process PipingASME B31.3 is the American Society of Mechanical Engineers code governing pressure piping in petroleum refineries, chemical plants, pharmaceutical plants, paper.
B
- BACnet, Building Automation and Control Networks, ASHRAE 135BACnet is the open communication protocol for building automation and control networks, developed by ASHRAE and standardized as ANSI/ASHRAE Standard 135 and ISO.
- Basic Process Control System, BPCSThe basic process control system, BPCS is the regulatory control layer of a plant. The DCS or PLC holding process variables at setpoint during normal operation..
- Batch ControlBatch control is the automation of recipe-driven production where a process executes as a sequence of phases, charge, mix, react, transfer, clean rather than st.
C
- Cable ScheduleA cable schedule is the master register of every electrical and instrumentation cable installed at a facility. It records cable number, type, size and core coun.
- Cause and Effect MatrixA cause and effect matrix is a tabular document that lays out the safety-instrumented and interlock logic of a plant in a row-by-column format. Rows are causes,.
- CFIHOS, Capital Facilities Information HandOver SpecificationCFIHOS, the Capital Facilities Information HandOver Specification, is an industry standard that defines what engineering and asset information an owner-operator.
- Control LoopA control loop is the closed sequence of field devices, signal paths, and control logic that holds a process variable at a setpoint. Every loop has a measuremen.
D
- Decommissioning data packageA decommissioning data package is the consolidated set of engineering records assembled before a plant or unit is taken out of service. It documents what is ins.
- Distributed Control System, DCSA distributed control system is a process-control architecture where field I/O, controllers, and operator workstations are distributed across a plant and connec.
F
- Factory and Site Acceptance Test, FAT and SATA factory acceptance test, FAT is the structured test of equipment or a control system at the vendor's premises before shipment. A site acceptance test, SAT rep.
- Foundation FieldbusFoundation Fieldbus, FF, sometimes written as FOUNDATION fieldbus is a digital all-or-nothing communications standard for process instrumentation. Unlike HART,.
H
- HART ProtocolHART, Highway Addressable Remote Transducer is a digital communications protocol that overlays a 1200-baud frequency-shift-keyed signal on top of the analog 4-2.
- HAZOP Guide Words, No, More, Less, Reverse, As Well As, Part Of, Other ThanHAZOP guide words are the seven standard deviation modes used in a hazard and operability, HAZOP study to systematically explore how a process parameter, flow,.
- Human-Machine Interface, HMIAn HMI is the operator-facing graphical layer of a control system. The screens, faceplates, alarm summaries, and trend displays the operator looks at while runn.
I
- I/O ListAn I/O list is a structured spreadsheet enumerating every analog input, analog output, digital input, and digital output a control system reads or drives. It is.
- IEC 60079, Explosive Atmospheres, Hazardous Area EquipmentIEC 60079 is the international standard series governing electrical equipment for use in explosive atmospheres, Ex equipment. The standard defines hazardous are.
- IEC 61511IEC 61511 is the international standard for functional safety in process industries, harmonized in the US as ANSI/ISA 84. It governs the full lifecycle of safet.
- IEC 81346IEC 81346 is an international standard for structuring technical systems and assigning reference designations to their parts. Co-published as ISO/IEC 81346, it.
- Instrument DatasheetAn instrument datasheet is the per-tag specification document that records every parameter needed to procure, install, calibrate, and maintain a field instrumen.
- Instrument IndexAn instrument index is the master register of every tagged instrument across a facility, with metadata richer than what fits in an I/O list. Teams use it as the.
- ISA 18.2, Management of Alarm Systems for the Process IndustriesISA 18.2 is the international standard governing the lifecycle management of alarm systems in DCS, SCADA, and PLC platforms across the process industries. It de.
- ISA 5.1ISA 5.1 is the North American standard defining instrument symbols and tag identification on P&IDs. The current revision is ANSI/ISA 5.1-2024. Every tag carries.
- ISA-88ISA-88, also IEC 61512 is the international standard for batch control. It defines a hierarchy of physical equipment, recipes, and procedural elements that lets.
- ISA-95ISA-95, also published as IEC 62264 is the international standard for integrating enterprise, ERP, business and control, DCS, PLC, SCADA systems. It defines a l.
- ISO 15926, process-plant lifecycle dataISO 15926 is the international standard for representing and integrating process-plant lifecycle information. It provides a common data model and a library of r.
L
- Ladder LogicLadder logic, LD is a PLC programming language that represents control logic as rungs of a virtual ladder, with input contacts on the left and output coils on t.
- Line ListA line list is the master register of every numbered process pipe in a facility, with metadata including line number, size, pipe spec, service, design temperatu.
- Loop DiagramA loop diagram, loop sheet is the drawing that shows one complete instrument loop at the wiring level. The field sensor, every junction box and terminal block,.
- Loop FolderA loop folder is the physical or electronic dossier of every document associated with a single control loop. The relevant P&ID page, the loop diagram, the instr.
- LOPA, Layer of Protection AnalysisLOPA, Layer of Protection Analysis is the semi-quantitative process safety technique used to determine whether the existing layers of protection adequately redu.
M
- Manufacturing Execution System, MESA manufacturing execution system is the software layer that sits between the BPCS and the ERP, executing production orders, tracking work-in-progress, recording.
- Marshalling CabinetA marshalling cabinet is the physical interface between the field cabling and the control-system I/O cards. Field cables terminate on terminal blocks in the mar.
- Mechanical Completion, MC and RFSUMechanical completion, MC is the milestone at which a system has been installed and inspected in line with the drawings and specifications, with construction pu.
- ModbusModbus is a simple master-slave communications protocol originally developed by Modicon in 1979. Its longevity is remarkable. Modbus RTU, over RS-485 serial and.
O
- Off-page connectorAn off-page connector is a P&ID symbol that hands a process line or instrument signal off to another drawing page. Drawn as a pentagon-shaped arrow with the des.
- OPC UAOPC UA, OPC Unified Architecture is a platform-independent, service-oriented architecture for industrial data exchange. It is the standardized way to connect co.
- Overall Equipment Effectiveness, OEEOEE is a composite metric of how productively a piece of manufacturing equipment is operating. It multiplies three factors. Availability, fraction of scheduled.
P
- P&ID vs PFDA process flow diagram, PFD sketches process intent. Major equipment, principal streams, mass and energy balance. A piping and instrumentation diagram, P&ID is.
- PFDavg, Average Probability of Failure on DemandPFDavg is the average probability that a safety instrumented function, SIF will fail to perform its safety action when demanded. It is the central metric of SIL.
- Piping and Instrumentation Diagram, P&IDA piping and instrumentation diagram, P&ID is the master process drawing of an industrial plant. It shows every piece of equipment, every pipe and pipe spec, ev.
- ProfibusProfibus, Process Field Bus is a digital fieldbus standard with two principal flavours. Profibus DP for fast device-level communications, drives, remote I/O, MC.
- ProfinetProfinet is the Siemens-originated industrial Ethernet protocol that succeeded Profibus DP for deterministic communication between PLC or DCS and field devices..
- Programmable Logic Controller, PLCA programmable logic controller, PLC is a ruggedized industrial computer that scans inputs, executes user logic, and updates outputs on a fixed deterministic cy.
S
- Safety Instrumented System, SISA safety instrumented system is a separate control system whose only job is to take a process to a defined safe state when a measurement crosses a trip threshol.
- Safety Integrity Level, SILSafety integrity level, SIL is a quantified bracket of how reliable a safety function must be. Per IEC 61511, ISA 84, every safety instrumented function gets a.
- SCADASCADA stands for Supervisory Control And Data Acquisition. It is the architecture for monitoring and controlling geographically dispersed assets like pipelines,.
- Scope freezeA scope freeze is the point in a turnaround or project schedule after which no new work may be added to the agreed scope without passing through formal change c.
- Sequential Function Chart, SFCSequential function chart is one of the five IEC 61131-3 PLC programming languages, designed for representing sequential and concurrent control logic graphicall.
- Spare I/OSpare I/O is the proportion of input and output channels and cabinet capacity deliberately left unused when a control system is sized, so future instruments can.
T
- Technical Bid Evaluation, TBEA technical bid evaluation, TBE is the structured comparison of vendor and contractor proposals against a project's technical requirements, scoring each bid on.
- TEMA, Tubular Exchanger Manufacturers Association StandardsTEMA is the trade association standard for shell-and-tube heat exchangers, defining the three-letter type designation that identifies the front head, shell, and.
- Tie-inA tie-in is the physical connection point where new piping, equipment, or instrumentation is joined to an existing operating system, typically during a revamp,.
- Trip ClassTrip class is a designation on a P&ID or interlock document that flags how a safety instrumented function, SIF responds to a measured deviation. Which hardware.
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