Automated PLC panel testing

PLC
1

Hello,

we are using Allen Bradlley controllogix PLCs widely, with controllogix & Flex I/O’s.
currently we do panel testing using 4-20 mA simulator, Frequency Generator, RTD sensors, Toggle switches (for Discrete signals) & lamps.

we want to atomize panel testing process, we are looking for ideas how to do panel testing automatic from Point I/O level.

currently we are working on idea to create demo control panel with analog outputs, discrete output which simulates actual panel’s analog inputs & discrete inputs.

anyone have different idea will be greatly appreciate.

Thanks.

Mehul

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2

@mehul280

Nice idea to automate the PLC testing.

You can also try this, little bit complex, Design a Control Panel (PLC or Micro-controllers based system) with inbult RS485 Communication and program the system to automate the AI, AO, DI, DO cards by sending respective signals.

You can design a graphics for the user. when user gives a selection, say testing for AI card or to choose required card say 7th AI card like that and to initiate the test. User can have the controls from the graphics to inject 4-20mA current either sink/source depends on selection.

The RS485 communication purpose is to communicate with the Main PLC system.

Also You can create a standard programs/files for each PLC manufacturer or their model.

Note : A Standard Program is required at both sides. If you are serious you can have a look at this.

Also share if you got any ides, share with us.

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3

Automated PLC panel testing refers to the process of conducting tests on Programmable Logic Controller (PLC) panels using automated methods and tools. This approach allows for efficient and reliable testing of the PLC panel’s functionality, performance, and adherence to specifications.

Here are the key steps involved in automated PLC panel testing:

Test Plan Development

Begin by creating a comprehensive test plan that outlines the specific tests to be performed on the PLC panel. This plan should include details such as test objectives, test cases, expected results, and acceptance criteria.

Test Environment Setup

Set up the necessary hardware and software environment for the automated testing. This typically includes connecting the PLC panel to a test bench or simulator, configuring communication interfaces, and preparing any required test fixtures or instruments.

Test Automation Framework

Develop or select a suitable test automation framework that provides the necessary tools and libraries for automating the PLC panel testing. This framework should support the programming language and communication protocols used by the PLC.

Test Script Development

Create test scripts or test cases within the automation framework to simulate different scenarios and inputs that the PLC panel will encounter during operation. These scripts should cover various functionalities, control logic, input/output operations, and communication aspects.

Test Execution

Execute the automated test scripts against the PLC panel. The scripts will send predefined inputs and commands to the panel, monitor the outputs, and verify if the actual results match the expected results. This can involve testing different modes of operation, error conditions, boundary cases, and stress scenarios.

Data Validation

Validate the data and responses received from the PLC panel during the testing process. Compare the actual values with expected values, and check for any discrepancies or errors. This includes verifying the accuracy of analog measurements, correct sequencing of digital inputs/outputs, and proper handling of alarms or error conditions.

Test Reporting

Generate test reports that provide a summary of the test results, including any detected issues, failures, or deviations from expected behavior. Include detailed logs, screenshots, or other supporting evidence for each test case. This documentation will help in troubleshooting and resolving any identified problems.

Regression Testing

As changes or updates are made to the PLC panel or its software, perform regular regression testing using the automated test suite. This ensures that previous functionality remains intact and that new changes do not introduce any unintended issues.

Continuous Improvement

Continuously improve the automated testing process by incorporating feedback, enhancing test coverage, and optimizing the test scripts and framework. This helps in increasing efficiency, reducing testing time, and improving the overall quality of the PLC panel.

Automated PLC panel testing enables faster and more reliable testing, reduces human errors, and ensures consistent test execution. It also facilitates thorough testing of complex control logic and extensive input/output configurations. By following these steps, you can establish a robust automated testing process for PLC panels, leading to improved quality and reliability in industrial control systems.