The PLC program logic, says when the level switch 1 and level switch 2 are both active, we need to have the motor connected to this output turned on. To test each output we just need to give the PLC an input signal and see if the digital outputs change as expected based on the PLC program. Let’s say that this push button is connected to the first digital input of the PLC. To test this input, all you need to do is to press the push button and see if the LED light for the first digital input on the card turns on. To do a FAT you need to test each of the PLC inputs and outputs one by one and make sure everything works properly based on the PLC logic.
Deviations or abnormalities observed during testing are documented in a problem report and corrected prior to shipment. The FAT is a customized testing procedure for different types of systems and the tests are executed before the final installation at the plant. A poor or rushed FAT can lead to missed non conformities, which can only then be corrected after the equipment is installed—which in turn can wreak havoc on a project schedule. User acceptance testing represents test scenarios designed to focus and measure the functionality of a system.
If something does not live up to the obligations spelled out in the contract, it must be rectified or legal action can be pursued. Alpha tests are internal and aim to spot any glaring defects, while beta testing is an external pilot-test of a product before it goes into commercial production. In my experience acceptance test are usually a subset of the functional tests and are used in the formal sign off process by the customer while functional/system tests will be those run by the developer/QA department. It’s important to note here that there are varying levels of an FAT.
An effective way to eliminate inefficiencies in installing industrial equipment is the key practice of performing factory acceptance testing (FAT). By simulating operating and failure modes, each component of a system is checked before leaving the factory. This gives operators the opportunity to ensure that the equipment is operating as intended and gives them the assurance that their top-quality equipment will operate properly from the get-go. Factory acceptance testing will also provide guides to proper installation, enabling operators to optimize installation time.
Real UAT examples can be real applications of a product to ensure its compliance with the business usage requirements from the end-user perspective. The tests should be developed and performed by the end users or the general audience. In software development, they are usually done by quality assurance engineers. FAT is typically performed at the manufacturer’s facility, ensuring that equipment functions optimally and complies with industry standards and customer requirements.
Getting through the FAT is another milestone in the project, as the software has been proven in design. The next step is to place the equipment in the field and verify everything again using the real world inputs and outputs. For example, inputs from either the field or the workstation software may be simulated to start one or more pumps. Some contracts require a Factory Acceptance Test (FAT) conducted at the contractor’s facility; such a test consists of the contractor, or the system programmer in particular, demonstrating that the program logic works correctly. With the PCLDs and PPC points lists in hand, the various processes of the design are simulated and the operations are verified. The test is usually performed with the completed panel, with the PPC and all terminations.
Basically, an FAT is a “factory debug” to assure that when the system arrives on site, it should be able to be installed and get up and running quickly and smoothly. If you’ve been wondering what exactly an FAT entails and why should get one, we’ve got some answers for you in this post. The importance of factory acceptance is to ensure smooth and efficient commissioning of the machine at the customer’s site. By identifying and correcting potential problems in advance, the risk of downtime and production disruptions is minimized. In addition, factory acceptance helps to strengthen the customer’s confidence in the quality and reliability of the machine. Further, performing a factory approval test is crucial to ensuring that once installed, the equipment will operate safely and optimally.
It is proven that when verifying, inspecting, and testing is performed prior to shipment it greatly reduces start-up issues once the equipment arrives at your site. With a thorough Factory Acceptance Test performed, you can be fully confident in the system you definition of factory acceptance testing are receiving and be ready to put it into production. A factory acceptance test (sometimes called factory approval testing, or simply FAT) is a series of functionality checks done on industrial equipment by a manufacturer before shipping to the end-user.
The purpose of the FAT is to ensure that the customer’s requirements are met. The Site Acceptance Test is performed directly at the customer’s site after a successful Factory Acceptance Test. It is used to ensure that the plant or machine has been properly installed and is operational.
These nonconformances, and any other issues discovered, are often also registered separately as punch items and followed up on by the commissioning team. If a product is found to be unacceptable at this stage, it can be sent back for modification, debugging, repair, or re-design before it can become a costly undertaking for the producer, as would be the case in a product recall. In my view the main difference is who says if the tests succeed or fail. Acceptance testing – test the product in its context, this requires (simulation of) human interaction, test it has the desired effect on the original problem(s). The more valuable input that is received from both parties, the more successful the test will be, which will help to facilitate a fast-track start up. All such issues are usually discussed with the client and mutually resolved.