A custom industrial machine should be accepted against documented requirements, not a general impression that it appears to work. Factory acceptance testing (FAT) and site acceptance testing (SAT) create a structured way to verify the machine before production responsibility transfers to the owner.

This guide explains how manufacturers can define practical acceptance criteria for a custom machine design and build project. It is intended for engineering, operations, maintenance, quality, and project teams preparing to buy or commission new automation equipment.

Why acceptance criteria should be written early

Acceptance criteria are most useful when they are developed with the machine requirements—not after fabrication is complete. Early agreement gives the builder and owner the same definition of success and identifies the parts, materials, utilities, inspection methods, and personnel needed for testing.

A good acceptance plan should answer four questions:

  • What functions and performance must the machine demonstrate?
  • How will each requirement be measured?
  • What test conditions, parts, and materials will be used?
  • Who reviews the results and approves exceptions?

The criteria should be specific enough to test while allowing documented engineering changes. Requirements such as “runs well” or “easy to use” are too subjective. A measurable requirement identifies the operating condition, expected result, test method, and allowable tolerance.

FAT and SAT serve different purposes

Factory acceptance testing is completed before the machine leaves the builder’s facility. It verifies as much of the design as practical while changes are still easier to make. Site acceptance testing takes place after delivery, installation, and connection to the owner’s utilities and surrounding equipment.

FAT can normally verify machine construction, control sequences, operator interfaces, alarms, guarding, dry cycles, representative process trials, and available performance requirements. SAT confirms that the installed machine works in its actual environment and integrates with production equipment, plant services, networks, and operating procedures.

SAT should not simply repeat the FAT. The two tests should be connected, but the site plan should focus on conditions that could not be fully represented at the builder’s facility.

1. Start with an acceptance matrix

Create a matrix that traces each important project requirement to a verification step. A useful matrix includes the requirement ID, description, acceptance threshold, test method, required test equipment, responsible party, result, and approval status.

Group requirements into practical sections:

  • Mechanical construction and maintainability.
  • Electrical panels, wiring, and controls.
  • Safety functions and protective measures.
  • Automatic and manual operating sequences.
  • Cycle time, capacity, and changeover.
  • Process quality and inspection.
  • Interfaces, data, recipes, and reporting.
  • Documentation, training, spares, and support.

This structure helps connect the early requirements and feasibility analysis to design reviews, fabrication, and final commissioning.

2. Define the test conditions

Performance results are meaningful only when the conditions are controlled. Identify the approved parts or samples, material condition, operator involvement, utilities, consumables, environmental conditions, production duration, and inspection method.

For equipment that processes multiple products, define which sizes, weights, geometries, or recipes represent the operating range. Testing only an easy sample can leave important limits unverified. If production material will not be available for FAT, document the substitute and identify what must be repeated during SAT.

3. Verify mechanical construction

Mechanical inspection should compare the finished equipment with approved drawings and specifications. Review the frame, access, guarding, fixtures, tooling, motion components, fasteners, lubrication points, utility connections, lifting provisions, and service clearances.

Check that normal maintenance tasks can be completed safely and that wear components can be reached and replaced. Verify that parts load, locate, clamp, process, and unload as intended across the approved range. Record measurements when alignment, runout, position, force, travel, or clearance affects the process.

BP Automation’s manufacturing and assembly process supports the build stage after engineering requirements and design have been established.

4. Test electrical and control functions

Controls testing should cover more than a successful automatic cycle. Verify power-up, initialization, mode selection, permissives, manual functions, automatic sequence, controlled stops, restart behaviour, alarm handling, and recovery from common faults.

A practical FAT checklist may include:

  • I/O checks for sensors, valves, motors, drives, and instruments.
  • PLC sequence and interlock verification.
  • HMI navigation, status, alarms, recipes, and user access.
  • Motion limits, homing, positioning, and fault recovery.
  • Communication loss and retained-equipment interface tests.
  • Backup, restore, and final software version records.

For related capabilities, see custom machine controls and PLC automation systems.

5. Validate safety requirements

Safety validation must follow the project’s approved safety plan and applicable owner requirements. The responsible parties should be identified before testing begins.

Test emergency stops, access interlocks, protective devices, safe stopping behaviour, reset logic, prevention of unexpected restart, manual-mode restrictions, and fault responses. Confirm that labels, signs, guarding, and operating instructions match the final machine. Any bypasses used during commissioning should be controlled, documented, and removed before acceptance.

6. Measure performance and process quality

Cycle time should be defined carefully. State where timing starts and stops, whether loading and unloading are included, and how many consecutive cycles are required. A single successful cycle does not demonstrate sustained operation.

Depending on the application, performance criteria may include:

  • Completed parts or cycles within a defined period.
  • Position, dimension, force, temperature, weight, or process tolerance.
  • Changeover time between specified products.
  • Reject detection and handling.
  • Alarm and downtime information.
  • Operation through a representative production run.

Define who judges part quality and which gauges, test methods, or samples will be used. If the machine includes cameras, sensors, or automated checks, the test plan should cover known good parts, known defects, boundary samples, and the required response. BP Automation also provides automated inspection system integration.

7. Test interfaces and data

Custom equipment often depends on upstream conveyors, downstream machines, robots, plant networks, databases, or production systems. List every external signal and define ownership for both sides of the interface.

At FAT, simulated signals can confirm the expected handshake and fault behaviour. SAT should then verify the real connection, including loss of communication, blocked downstream equipment, unavailable material, incorrect data, and recovery after an interruption.

8. Control deficiencies and changes

Not every observation should prevent shipment, but every unresolved item should be visible. Use a deficiency log that records the issue, requirement reference, severity, owner, target date, corrective action, retest result, and approval.

Define which conditions are required before shipment, which can be completed during installation, and which require an approved deviation. Verbal agreements should be added to the project record so they do not become disputes at final acceptance.

9. Confirm documentation, training, and support

Acceptance is not limited to machine performance. Confirm delivery of the required drawings, manuals, software backups, parts lists, maintenance instructions, inspection records, and training materials. Record final hardware and software versions after all accepted changes.

Training should reflect the needs of operators, maintenance personnel, and technical administrators. The support plan should identify warranty contacts, response expectations, recommended spares, preventive maintenance, and how future software changes will be controlled. Review BP Automation’s maintenance and support services when planning lifecycle requirements.

Information to prepare before FAT

  • Approved machine requirements and latest drawings.
  • Acceptance matrix and test procedures.
  • Representative parts, materials, tooling, and consumables.
  • Approved quality standards and measuring equipment.
  • Required owner personnel and decision authority.
  • Interface simulations or connected test equipment.
  • Safety validation responsibilities and records.
  • Deficiency classification and approval process.

Custom machine acceptance planning in Alberta

BP Automation is based in Edmonton and supports custom industrial machine projects across Alberta and Western Canada. A clear FAT and SAT plan helps the owner and builder identify risks earlier, organize the correct test resources, and create an objective record of machine readiness.

The acceptance plan should match the complexity and risk of the application. It should also remain connected to the approved requirements as the design develops. BP Automation’s industrial machine design process covers the engineering stage that turns those requirements into a buildable system.

Frequently asked questions

Who should attend a factory acceptance test?

Attendance depends on the project, but may include representatives from engineering, operations, maintenance, quality, safety, and the machine builder. The owner should identify who can approve results and deviations.

How long should a FAT run?

There is no universal duration. The test should be long enough to complete the approved procedures and demonstrate the required performance under representative conditions. Complex processes or multiple product formats may require several test stages.

Can a machine ship with open deficiencies?

Only if the owner and builder agree in writing. The open items, risk, corrective action, responsibility, target date, and required retest should be documented before shipment.

What changes between FAT and SAT?

SAT adds the real installation environment: plant utilities, production material, surrounding equipment, networks, operators, and site procedures. It confirms that the delivered machine performs after transport, installation, and integration.

Should training be completed before acceptance?

Training requirements and timing should be defined in the contract or acceptance plan. Operator and maintenance training is commonly tied to installation, commissioning, and the transition to production.

Planning a custom machine project? Contact BP Automation or call (780) 448-9338 to discuss the process, requirements, and acceptance criteria.