Do you know how important drawings are when troubleshooting lines in the manufacturing field? The answer is simple. They are a must-have! So let me tell you the story of what happened when I was assigned to solve a site issue without them.

Troubleshooting on a manufacturing

The Three Items You need to Troubleshoot Lines in the Manufacturing Field

When troubleshooting, you typically need three things at hand to solve the problem: 

  • PLC code,
  • Drawings, and 
  • HMI faults to show you where the issues are. 

Recently, I faced a particular situation. 

The existing lines lost all their drawing packages, which meant the only item I had access to was the PLC code. 

This tricky scenario presented me with a first-time challenge. 

How to Fix a Station Without Drawings 

One of the good things about the engineering field is that designs are standardized, which makes processes similar across different industries. Pairing the operator’s knowledge with your expertise is a great match. 

When it was my turn to support a production team without drawings, I followed this procedure, which can help you too if facing a similar situation:

1) Find some operators that tell you how the machine typically runs. Keep them by your side throughout the task. 

2) Look inside the panel to see what type of hardware is installed. For example:

Notice the safety design features

  • Does the system have safety relays or safety I/O cards? 

How does the PLC communicate?   

  • Is it hard-wired to each I/O card? 
  • Is it ethernet-based I/O cards? 

Go through the ethernet switches 

  • Are they managed or unmanaged switches? 

And, at last, the power system 

  • Do they have separate power for the PLC/HMI/Ethernet switch to keep them running while throwing the main disconnect? 

Checking out those items matters in troubleshooting. A simple inspection can help you figure out how the system was designed and how the machinery works.    

3) In my particular situation, I only found one main disconnect. That meant the solution called for adjusting the ‘Cycle Power’ or looking at the faults registered on the HMI screen. HMI may not always have the best description but it will never fail to point you in the right direction.   

At this moment, you need to trust yourself and trace out the happenings based on the “Faults” status on the HMI screen. The help of the operator is critical because he is the one who can guide you and point you in the direction of other problems that could have caused the failure. 

Needless to say, a little further down the road, I solved the issues without any drawings at hand!

Engineer Your Way In

That was a classic example of what makes a good engineer: not being afraid to make mistakes and using common sense to get problems solved.

Even though my situation seemed simple, it took a lot of creativity and hard work on the spot to come up with a solution that worked.

If you are ever in a pinch and wonder what the best solution would be, I always go back to the KISS method:

Keep It Simple, Stupid!

Contact Me 

If you wish for more information or need advice, please reach out to Verdusco Consulting or message me directly at: