Verify

Identify the tests and measurements to implement to validate a system's operation

I fulfilled this requirement through the underwater watch project. During this project, the main question was to verify if the system was able to decode under certain conditions. I was first able to identify the constraints under which the system must operate.

Propose a corrective solution for a malfunction

During the variable speed drive project, I found several possible solutions to correct the drive's startup logic error.

I could change the input detection mode from edge detection to state detection, add a physical delay, remove a safety feature on the control word, implement a logical AND on the two inputs, or set one of the inputs to always be in the "true" (high) state.

I tried this last solution; however, it did not change the drive's state. The drive only detects edge changes; if the drive starts with COM-V in a high state, it will not be detected.

The simplest and easiest solution to implement was to change the input detection mode. After researching and modifying the parameter, the cabinet starts correctly.

Evaluate the root cause of a malfunction

During the variable speed drive project, I had a problem with the startup command for the control cabinet. When I press the "Low Speed" button on the HMI, nothing happens. The cabinet was declared "HS" (out of service / dead). After replacing the drive, I had concluded that the drive itself was defective.

Previous tests were executed without anomalies using a control box I built myself. However, as soon as I switch the control over to the cabinet's boards, the drive refuses to start.

By measuring the outputs of the control boards with an oscilloscope, I notice that in the initial state, both outputs are at state 0, and when the user presses the "Low Speed" button, they both switch to 5V.

When I observe the drive's states, in the case where the buttons are activated one by one, the state change occurs correctly. In the case where both inputs change state at the same time, no state is changed.

If I take my custom control box again and change the state of both outputs at the same time, I can observe the same phenomenon. I therefore succeeded in reproducing the conditions that cause the malfunction to appear and in identifying the nature of the malfunction.

Certify the operation of new industrial equipment

As part of the underwater watch design project, I developed and implemented a test protocol aimed at certifying the proper operation of this equipment. I compiled a list of tests to be performed to verify the system's correct functioning. By verifying the requirements set out in the specifications document (cahier des charges), I found that the system did not meet the established specifications. The problem was that the system worked correctly in the pool (with 86% transmission), but I was able to detect that it only worked at a single distance, thus not meeting the requirements of the specifications.

However, I was subsequently able to propose an alternative operational solution.

Produce a test procedure to validate a system's conformity

For the variable speed drive project, I was able to produce and carry out a test procedure for the new drive.

The document is intended for operators and it lists the tests and trials to be performed with the objective of verifying the drive's conformity with the technical requirement specification.

To do this, I first list the preliminary checks (Verification of mechanical conformity, wiring checks, adherence to distances between electrical and mechanical parts, and finally, overall electrical tests and measurements).

I then carry out power-on tests of the cabinet; the objective here is to functionally check the cabinet and to test for errors and drive faults. Finally, I perform load tests followed by environmental qualification tests, including endurance, EMC (CEM), shock, and vibration tests.

With this protocol, I verify each function of the technical requirement specification, respecting the required proof methods (Inspection, analysis, demonstration, and/or test).