SCADA FAT Procedure: A Step-by-Step Practical Guide

The objective of Factory Acceptance Testing (FAT) is to verify the SCADA system’s hardware quality, system setup, and specification compliance before delivering to the project location.

In short, it guarantees that the SCADA system functions properly and meets customer needs.

During the FAT, tests are carried out to ensure that the complete system’s design, including the 

• HMI, 
• Network infrastructure, 
• Controllers, and all associated applications

has been correctly implemented.

SCADA (Supervisory Control and Data Acquisition) systems are essential for the real-time monitoring & control of the industrial processes in the power, water, oil and gas, and manufacturing industries.

Before the SCADA system is installed on-site, a Factory Acceptance Test (FAT) assures that all 

• Hardware, 
• Software, 
• Logic, and 
• Communications 

fulfill the client’s technical and functional specifications. 

The FAT process assesses performance, reliability & system integration in a controlled industrial environment.

What is the SCADA FAT?

SCADA Factory Acceptance Testing (FAT) is a pre-installation test performed at the vendor or integrator’s location. It simulates actual plant operating conditions to:

• Detect system faults,
• Confirm I/O mapping accuracy,
• Verify the HMI graphics and alerts,
• Test PLC/RTU connectivity and
• Ensure overall operation.

Step-by-Step SCADA FAT Procedure

The following is an in-depth explanation of every step that is involved in the SCADA FAT procedure. 

For the purpose of integrating them into manuals, training materials (or) FAT protocols, each point has been explained elaborately in detail by us.

Step-1). Pre-FAT Preparation

It is the responsibility of the Pre-FAT stage to ensure that all of the foundational components are in place so that the Factory Acceptance Test may be carried out successfully. 

It is recommended that the team start by doing an in-depth assessment of the control concept document that has been finalized. 

This document outlines the way in which the SCADA system will communicate with the various plant components. 

In the following step, it is necessary to check out and give approval to all of the 

• PLC, 
• HMI and 
• SCADA architecture drawings. 

These drawings serve as the blueprint for the 

• Wiring, logic development & 
• System integration procedures.

 In addition, it is of the highest priority to ensure that all of the necessary software licenses, such as those for the 

• SCADA platform, 
• Historian, 
• OPC servers, 
• Engineering tools, and so on

are valid and operating in order to prevent licensing problems during testing. 

Be certain that all of the control panels have been thoroughly wired and terminated in accordance with the schematics, with the appropriate tagging and cable dressing, before the FAT.

It is necessary to perform a thorough inspection and power up all of the hardware, including 

• Communication modules, 
• RTUs, 
• PLCs and 
• Instruments 

in order to confirm that they are functioning properly. 

By completing these steps, the probability of experiencing delays and problems during the FAT is decreased.

Step-2). FAT Setup

The purpose of this phase is to create a controlled test environment that is designed to simulate the characteristics of the actual site as accurately as feasible. 

Make sure that the appropriate communication channels are configured and tested before starting the process of connecting the PLCs to SCADA/HMI workstations. In conditions where field devices are not available, it is possible to replicate analog & digital input/output signals by utilizing I/O simulators (or) test benches. 

Because of this, the engineering team is able to check field responses without dispatching personnel to the location. 

It is therefore necessary to configure the SCADA network by establishing communication links through the utilization of suitable media such as 

• Ethernet, 
• RS-485, 
• Fiber optics (or) serial cables, 

depending on the design of the system.

In case that it is necessary, this also involves the configuration of switches, routers, and firewalls. 

The 

• SCADA server, 
• Historian, 
• Engineering station, & 
• Backup systems 

must all be installed and completely configured. 

This will ensure that all of the subsystems, such as 

• Redundancy, 
• Alarm recording, and 
• Data archiving

are functioning as they were designed. 

Before the simulation starts, a proper FAT setup assures that all of the gear and software will be integrated without any problems.

Step-3). SCADA System Verification

After the system has been put into operation, the priority will shift to verifying the functioning and usefulness of the SCADA interface. 

Commence with the HMI screen verification process, which involves examining the graphical user interface to determine whether (or) not it is consistent with licensed mimic diagrams. 

Each graphical element, such as valves, pumps, and motors, ought to be appropriately color-coded, clearly labeled, and dynamically updated in real time based on the input signals (or) simulations. 

After that, carry out testing for alarms and events. In order to ensure that alerts are logged, categorized

Ex: Critical, Major (or) Minor

& displayed with the appropriate visual and sounds signals, alarms should be triggered at various different thresholds. 

Check to see that the operations of the alarm acknowledgment & reset are functioning as planned. 

Log sample data for both the real-time & the historical views, making sure that the data is logged with the appropriate time stamps and displayed using tools that are easy to use for zooming, panning, and scaling. 

This is especially important for testing trends and historians. 

Additionally, it is necessary to test the levels of user access as well as the cybersecurity. 

In order to restrict access appropriately, users should be categorized according to their roles 

Ex: Operator, Supervisor (or) Administrator.

Verify the policies about the strength of passwords and the audit trail logging for each and every user action. 

On account of this, the SCADA system is guaranteed to be user-friendly, safe, and completely operational.

Step-4). PLC & RTU Functionality Check

Validating the basic control logic & field communication that is currently being controlled by PLCs and RTUs is the primary priority of this step. 

To start, using test kits, execute an input/output simulation on the programmable logic controller (PLC) in order to verify each input/output point against the tag list & wiring design. 

It is imperative that the SCADA system reliably reads both digital & analog values and reflects such readings. 

The next step is to assess the logic of the PLC programming, which may be

• Ladder logic, 
• Function block diagrams (or) 
• Structured text. 

This is done by simulating real-world process conditions, such as a motor overload (or) a valve position failure. 

Redundancy checks should be performed by manually removing one controller in order to verify that the system will automatically switch over to backup units if it supports redundancy for the system. 

Also, verify the logic of the interlocks, making sure that operations only continue when the conditions are met in a secure manner. 

Finally, simulate the flow of data between RTUs, instruments & SCADA servers in order to test all of the supported communication protocols. 

These protocols include 

• Modbus RTU/TCP, 
• DNP3, 
• IEC104 and 
• Proprietary protocols. 

This demonstrates that the logic behind the automation is dependable and free from risk.

Step-5). Communication Testing

When it comes to the reliability of a SCADA system, robust communication across components is absolutely necessary. 

Start by verifying communication links that are point-to-point and network-wide. 

This will ensure that all devices (PLCs, RTUs, HMIs & SCADA servers) are able to exchange data without any interruptions. 

Test protocols that are based on serial and Ethernet, such as Modbus RTU, Modbus TCP, Profibus & Profinet, making sure that the signal integrity, addressing, and polling intervals are all proper. 

Validating DNP3 & IEC 60870-5-101/104 connectivity & performance during simulated loss (or) reconnection conditions is necessary if your system makes use of utility-grade protocols.

Additionally, verify the OPC DA/UA server-client connections in order to make interaction with third-party software possible. Disabling a network link (or) server and determining whether or not traffic can be diverted via backup interfaces without causing any loss of data is an essential part of redundancy and failover testing. 

Having a communication arrangement that has been thoroughly tested guarantees reliable SCADA performance regardless of the network conditions.

Step-6). Integrated System Simulation

The system integration simulation is the component of the FAT that contains the maximum depth of information. 

In this section, engineers mimic actual plant operating conditions in order to test the operation of the system from start to end. 

There are a wide range of conditions that could occur, such as

• Power outage, 
• Trip of the equipment, 
• Emergency stop (or) 
• Conditions involving interlocks. 

PLCs, HMIs, SCADA screens, & historian logs should all appropriately reflect each event according to the specifications. 

Not only should the activation of interlocks be recorded as events or alerts, but they should also prevent harmful processes from occurring. 

In that case the conditions are normalized, alarms should be triggered in real time with the appropriate classifications, and they should be cleared. 

In the audit log, each and every action taken by the user, including acknowledgements, resets, and control instructions, should be recorded and made available. 

The testing of redundancy switching must be performed under actual load conditions in order to ensure that the system is available continuously. 

Additionally, the reaction time from the SCADA to the PLC should be measured in order to ensure that the system satisfies the performance criteria. 

This final test verifies that the fully integrated control & monitoring system is both reliable and trustworthy in terms of its integrity.

Step-7). Documentation & Reports

As soon as all of the tests have been successfully completed, the attention will shift to the final documentation & reporting. 

Take screenshots that are extremely thorough for each test conditions, giving particular attention to alerts, trends & logic executions. 

Test data sheets should be used to record the results, with parameters such as

• Input values, 
• Expected outcomes, 
• Actual outcomes & 
• Observations 

being noted inside the sheets. 

It is imperative that each and every task on the FAT checklist be noted as accomplished and signatures are obtained from both the integrator & the representative of the customer. 

In case any deviations or problems happened during the testing process, they had to be meticulously documented in a non-conformance report (NCR), together with the remedial action plans and the results of the retest. 

There should also be 

• Updated I/O lists, 
• PLC programs, 
• HMI configuration files, 
• Network architecture diagrams, & 
• Cybersecurity 

measures included in the final documentation. 

The documentation that has been thoroughly developed serves as the basis for the Site Acceptance Test (SAT) and any subsequent audits, so ensuring that the project continues to be acceptable and can be maintained.

Conclusion

It is essential to conduct a comprehensive SCADA FAT in order to ensure the successful completion of the activity. 

It not only enhances client confidence but also prevents costly onsite failures. Cross-functional collaboration among engineering, QA, as well as client teams is essential for an effective FAT.

The SCADA system can be confidently dispatched for Site Acceptance Testing (SAT) & final commissioning after FAT is approved.