Integration and AI Glossary

39 of 39 terms

PLCProgrammable logic controllerPlant and equipment

The industrial computer that runs a machine or a process. Rugged, deterministic, and designed to do the same thing reliably for twenty years rather than to be flexible.

What it means for your budget: Its age sets your options. A controller from the last decade will usually offer an open protocol and cost days of work; one from the 1990s may need a gateway, a driver licence, or reading through the machine's own SCADA instead.

SCADASupervisory control and data acquisitionPlant and equipment

The system operators watch and act through — screens, alarms, trends — sitting above the controllers.

What it means for your budget: Frequently the cheapest place to get data, because it already talks to everything. Reading from SCADA instead of from thirty controllers can remove most of an integration budget.

HMIHuman-machine interfacePlant and equipment

The screen on or beside a machine. A local, single-machine version of SCADA.

What it means for your budget: Where a machine has an HMI and nothing else, a camera reading that screen is a genuine route to the data. Unglamorous, and cheaper than the alternatives more often than engineers admit.

HistorianPlant and equipment

A database built for time-series plant data, storing values with timestamps and quality flags at high volume for years.

What it means for your budget: If you have one, you have the operating history that makes analytics possible. If you do not, budget for a year of collection before anything can learn from patterns.

MESManufacturing execution systemPlant and equipment

The layer between the business system and the plant: what to make, in what order, on which line, and what actually happened.

What it means for your budget: The most common thing an SME is sold when what it needed was three integrations. Full MES implementations are long and expensive; scope hard against what you actually cannot do today.

OTOperational technologyPlant and equipment

Everything that touches the physical process — controllers, sensors, drives, safety systems. Distinguished from IT, which handles information.

What it means for your budget: The distinction decides who does the work. OT work needs people who will not take a line down to install a patch, and that competence is priced differently from IT support.

FieldbusPlant and equipment

A digital network connecting controllers to field devices — PROFIBUS, Modbus RTU, CANopen, DeviceNet. Mostly serial, mostly predating industrial Ethernet.

What it means for your budget: Fieldbus means a gateway, and a gateway means a site survey. Not expensive, but not something to discover after a fixed-price quote has been signed.

4–20 mA loopPlant and equipment

The analogue standard for process instruments. Current, not voltage, so it is immune to cable resistance, and 4 mA rather than 0 means a broken wire is distinguishable from a zero reading.

What it means for your budget: Readable in parallel with a cheap module, which makes it one of the least expensive retrofit routes. It carries one value per loop, so a machine with twelve things worth measuring needs twelve loops.

Dry contactVolt-free contactPlant and equipment

A relay output that simply opens or closes a circuit — running, stopped, faulted, cycle complete.

What it means for your budget: The cheapest data on any machine and the most overlooked. Counts and run time from dry contacts answer a surprising share of the questions people commission much larger projects to answer.

P-F intervalPlant and equipment

The time between a failure becoming detectable and the equipment actually failing. The number that decides whether condition monitoring is worth anything.

What it means for your budget: Months means monitoring buys planning. Hours means it buys an alarm you cannot act on, and the money is better spent on a spare. See the predictive maintenance screener.

Purdue modelPlant and equipment

The reference architecture that layers a plant from field devices at Level 0 to the enterprise at Level 4, with an industrial DMZ between plant and business at Level 3.5.

What it means for your budget: Not academic. It is the vocabulary a security review will use, and the shape of it decides where the firewalls and the money go.

IP ratingIngress protectionPlant and equipment

Two digits: solids, then water. IP66 is dust-tight and resistant to powerful jets; IP69K adds high-pressure hot water.

What it means for your budget: Under-specifying costs you the device eight months later; over-specifying costs you cooling and access. In a tropical climate the real hazard outdoors is condensation, not rain.

Industrial DMZIDMZ, Level 3.5Networks and security

A middle zone between the plant and business networks where data is handed off, so nothing crosses directly in either direction.

What it means for your budget: On an SME site this is frequently one hardened host and a firewall rule set rather than a data centre. It is the single change that improves the most findings in a segmentation review.

SegmentationNetworks and security

Dividing a network so that a problem in one part does not become a problem everywhere. In plants, keeping the control network apart from the business network.

What it means for your budget: Far cheaper before an integration than during one. During, it is a change request against a signed scope; after, it is an incident.

Air gapNetworks and security

The claim that a network has no connection to anything else. Almost always untrue by the time somebody says it out loud.

What it means for your budget: Treat as a hypothesis to be tested. The USB stick, the vendor's cellular router and the engineer's laptop are the three findings, and they are on nearly every site.

Jump hostBastion, remote access brokerNetworks and security

A controlled machine that vendors and engineers connect through, rather than reaching equipment directly. Sessions are opened on request, recorded, and closed.

What it means for your budget: Modest cost, and it is what replaces standing VPN accounts. It also produces an access record, which is what an auditor or an insurer asks for first.

Data diodeNetworks and security

Hardware that physically permits data to travel in only one direction, out of a protected network.

What it means for your budget: Expensive, and genuinely unbypassable. Justified where a regulator or a safety case requires it, and over-specified almost everywhere else — a firewall with a rule somebody owns is usually the proportionate answer.

Edge deviceEdge gatewayNetworks and security

A small computer sitting near the equipment that collects, buffers and forwards data, and can keep working when the link to anywhere else is down.

What it means for your budget: The standard shape of a modern integration. Buffering is the feature that matters: it is what makes a site with intermittent connectivity workable rather than a permanent problem.

RPARobotic process automationAI and automation

Software that drives existing applications the way a person would — clicking, typing, copying between screens.

What it means for your budget: Fast to build and brittle by nature, because it depends on screens not changing. Right where no API exists and the process is stable; wrong as a permanent substitute for integration.

Agentic workflowAI and automation

An automation where a language model decides the sequence of steps rather than following a fixed one, calling tools as it goes.

What it means for your budget: Genuinely useful where the work varies case by case, and genuinely harder to test than a rule. Budget for the supervision and the audit trail, not only the build.

Computer visionAI and automation

Getting information from images — reading a gauge, counting units, checking a label, spotting a defect, recognising a container number.

What it means for your budget: The camera is the cheap part. Lighting, mounting and the handling of the cases it gets wrong are the project, and they are where the cost sits.

Predictive maintenancePdM, condition monitoringAI and automation

Using measured condition to predict failure before it happens. Works only where degradation is measurable and there is time to act on it.

What it means for your budget: The term is applied to things it cannot do. Against random electronic failure there is nothing to detect; against consumable wear, counting is cheaper and more reliable. Ask which failure mode before anyone quotes.

Digital twinAI and automation

A live model of a physical asset or process, updated from real data, used to simulate or predict.

What it means for your budget: The most over-claimed term on this list. A dashboard is not a twin. Real ones are expensive, need a validated model, and are justified on high-value continuous processes rather than on a packing line.

Model driftAI and automation

The gradual decline in a model's accuracy as the world stops resembling the data it learned from.

What it means for your budget: The reason an AI system needs an operating budget rather than only a build budget. Something has to notice the decline, and somebody has to be responsible for retraining.

Human in the loopAI and automation

A design where a person reviews or approves the automation's output before it takes effect.

What it means for your budget: Reduces risk and reduces the saving, and both have to be in the business case. Automation that is 90% accurate with review is frequently worth more than one that is 95% accurate without it.

Exception pathAI and automation

What happens to the cases the automation cannot handle. Every automation has one, whether or not it was designed.

What it means for your budget: Where automation business cases go wrong. If 20% of cases go down the exception path and nobody planned it, most of the promised saving is still being done by hand.

Retrieval-augmented generationRAGAI and automation

Giving a language model access to your own documents at the moment of answering, rather than training it on them.

What it means for your budget: The usual answer for anything involving your manuals, procedures or records. Cheaper and more controllable than fine-tuning, and the answer can be traced to a source — which is what makes it defensible.

Discovery phasePaid discovery, survey phaseCommercial

A short paid engagement that establishes what is actually on site and produces the specification the build is quoted from.

What it means for your budget: The cheapest money on an integration project. It costs a fraction of the build and it is what makes a fixed price meaningful rather than a contingency you are paying for.

As-built documentationCommercial

Drawings and schedules reflecting what was actually installed, as opposed to what was designed.

What it means for your budget: Its absence is a cost driver on every project. The survey to reconstruct it happens either before the quote or during the build, and it is much cheaper before.

Tag listPoint list, I/O scheduleCommercial

The itemised list of every value to be read or written, with its address, type, units and range.

What it means for your budget: The single most useful document you can produce before going to market. Vendors quoting without one are quoting a guess, and the variation later will not be a guess.

Vendor lock-inCommercial

Being unable to change supplier without replacing the system, because the data, the interfaces or the licences belong to them.

What it means for your budget: Priced in the fifth year, not the first. Ask what happens to your data if you leave, and get the answer in the contract rather than in the meeting.

Total cost of ownershipTCOCommercial

Build, plus licences, support, hosting, and the hours somebody spends on it each month, over the life of the system.

What it means for your budget: Running cost typically lands between 15% and 22% of the build each year. A business case that omits it is not a business case.

HandoverCommercial

The point at which the system becomes yours to run — with documentation, credentials, source, and somebody trained to use them.

What it means for your budget: Specify what handover includes before signing. Source code, credentials and the right to engage another integrator are all things people discover they do not have at the worst moment.

ISO/IEC 42001Assurance and compliance

The management system standard for artificial intelligence, published in 2023. Certifiable, and structured like ISO 27001 with AI-specific requirements added.

What it means for your budget: Increasingly asked for in tenders. The distinctive requirement is the AI system impact assessment — the effect on people affected by the system — which has no ISO 27001 equivalent and is where most organisations find their gap.

Statement of ApplicabilitySoAAssurance and compliance

The document recording which standard controls apply, which are implemented, and why any are excluded.

What it means for your budget: An auditor asks for it early. Writing it honestly is a week; reconstructing it under audit is considerably worse.

NonconformityMajor, minor, findingAssurance and compliance

A failure to meet a requirement, raised at audit. A major stops certification; a minor delays it.

What it means for your budget: The distinction is what makes gap analysis worth doing beforehand. Majors cluster in leadership, risk assessment and evidence that the system is actually operating.

TraceabilityAssurance and compliance

Being able to show, after the fact, what a system did and why — inputs, decisions, versions, who changed what.

What it means for your budget: Cheap to design in and expensive to add. Where a regulator, a certifier or a customer audit is in the picture, treat it as a requirement rather than a feature.

ValidationAssurance and compliance

Demonstrating that a system does what it is required to do, with evidence, under a defined protocol.

What it means for your budget: Typically a fifth of project effort where it applies, and it applies more often than people expect once a certifying body or a class society is involved.

Functional safetySIL, IEC 61508, IEC 61511Assurance and compliance

The discipline covering systems whose failure could hurt somebody — interlocks, emergency stops, protective functions.

What it means for your budget: A different project with a different review and different competence requirements. If an integration touches a safety function, independent review is not optional and cannot be compressed.