Hidden dangers during commissioning

Article#: 00099

Date: 2024-10-01

Author: Radim

Commissioning is an essential phase in any automation project. It's the point where theory meets reality, and systems come to life for the first time. However, it is also one of the most dangerous phases for engineers, technicians, and operators. As an automation engineer, I've seen first-hand how quickly things can go wrong during commissioning. The reason is simple: nothing has been fully verified at this stage, and blindly trusting the system can lead to catastrophic consequences.

Why is commissioning so risky?

1. Unverified code and logic: Before commissioning, the control logic has often not yet been tested in the real environment. Errors, overlooked or unconsidered situations can lead to unexpected behaviors. Motors and pneumatic actuators can start without warning, safety devices may not work and critical processes may fail.

2. Uncalibrated sensors and actuators: At the start of commissioning, the inputs and outputs of the system (such as sensors and actuators) are often uncalibrated. This can lead to inaccurate data or incorrect actions, creating dangerous situations like overpressure, overheating, or even mechanical failure.

3. Communication failures: Automation systems rely heavily on communication between different devices, controllers, and software systems. Early in commissioning, these communication lines may not be fully established, causing misinterpretation of commands or data, which can trigger unintended actions.

4. Inaccurate system models: Simulations and preliminary tests can only represent part of reality. The real system may behave differently due to unforeseen environmental factors, hardware variability, or interaction between subsystems.

5. Wiring errors: Incorrect wiring is a common hazard during the early stages of commissioning. Wires may be crossed, mislabeled, or improperly connected, leading to short circuits, power surges, or unintentional energizing of equipment. It's crucial to measure every wire and conductive part of the machine to ensure it is safe. Even when the wiring looks correct, measuring voltage, grounding, and continuity before powering up can prevent electric shocks or machine damage.

6. Human error: Misconfigured parameters, forgotten settings, incorrect wiring, carelessness, negligence, misinformation or trying to speed up the work can cause serious accidents.


Key safety practices for commissioning:

1. Assume nothing works: Start with the mindset that nothing is verified. Treat every system, device, wire, and signal as if it could fail or behave unpredictably.

2. Progress systematically in small steps: Break down commissioning tasks into small, controlled steps. Test each component or subsystem independently before integrating it into the larger system.

3. Measure before powering on: Always use a multimeter or other testing equipment to check the voltage, grounding, and continuity of wires and conductive parts before powering up the system.

4. Always have emergency stops: Ensure that physical and software-based emergency stops are functional and accessible. In dangerous situations, being able to quickly halt the system can save lives and equipment.

5. Use temporary safety measures: Before permanent safety mechanisms are in place, implement temporary barriers, interlocks, or guards to reduce risk.

6. Involve the whole team: Ensure that all stakeholders, including safety officers, operators, and maintenance staff, are aware of the dangers and the stage of commissioning. Clear communication can prevent accidents.

Commissioning can be one of the most dangerous phases in automation, but with proper planning, caution, and respect for the risks, it can be conducted safely. Always approach commissioning with the assumption that nothing works as expected until it has been thoroughly tested and verified.

© Radim-Automation, 2020–2025. All rights reserved.
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Comment#: 00001

Date: 2024-10-01

User: Radim

If possible, gain experience with sensors and actuators during the programming and development phase, i.e. before commissioning. In this way, you will know how the device behaves, which states it can assume under different conditions and how to control it. The complete consideration of all possible states that you have encountered in practice ensures additional safety during commissioning.

Comment#: 00002

Date: 2024-10-01

User: Radim

Do not carry out any quick actions under power or without activating the safety measures! It is not worth saving a few minutes at the expense of risk.

Comment#: 00003

Date: 2024-10-01

User: Radim

Watch out for changes to the settings that could be made by another person or that could be caused by switching the device off and on. Always check the settings carefully!

Comment#: 00004

Date: 2024-10-04

User: Radim

Drive systems may perform unexpected movements because of incorrect wiring, incorrect settings, incorrect data or other errors!

Comment#: 00005

Date: 2024-10-04

User: Radim

Failure to follow these instructions can result in death, serious injury, or equipment damage.