Stop "Easter-Egging" & Improve Logic in Troubleshooting
Electrical Troubleshooting Weaknesses
A common problem area for most industrial facilities is downtime due to problems with electrical equipment. In today’s world of streamlining and lots of talk about improving maintenance efficiencies, it sometimes surprises me that so little investment is made into one of the leading causes of maintenance problems – namely weaknesses in troubleshooting skills. This is particularly problematic in electrical and automation type equipment, where the problems can be difficult to find.
Here are some of the major problem areas that I’ve noted over the years, along with 7 recommendations to resolve them. There are obviously situations where these need to be adjusted, but this general format is very helpful to a manager trying to develop improved troubleshooting patterns at their facility.
1) Understanding Electricity Basics - By far, the biggest problem is an inadequate understanding of Basic Electricity! Even techs who completed internships or have 2-year AAS degrees are often very weak in this area. If their first mentors/jobs don’t help them learn to apply what they learned in school – it fades away and they begin to simply ‘perform steps’ and ‘memorize tasks’. This can get them through most daily PM’s – but any tech who doesn’t have a solid, working understanding of electricity will struggle at troubleshooting any real electrical problem and will end up guessing, part-swapping, and other bad behaviors.
2) Poor Troubleshooting Logic – Unless a technician is taught to use a logical methodical approach to troubleshooting, they often miss obvious things that could speed up troubleshooting efforts, and/or they tend to go in circles. Interestingly, sometimes techs with a great understanding of electricity will still struggle to troubleshoot because they aren’t using a logical approach. A sample 7-step troubleshooting method that works well for typical industrial plants is shown at bottom of this page as an example.
3) Not finding the cause of the failure – This is a huge weakness across nearly every industry. Swapping the component out because it is obviously ‘smoked’ doesn’t prevent the replacement part from also being smoked. Techs often need to think hard about this step and it typically requires a good understanding of basic electricity and of the components or systems involved. Knowledge is power on this step – and the lack of knowledge leads to problems in many cases…
Manager Tip – You can help this by forcing your techs to always explain what caused the problem they found when they report. If you do it often, it’ll become part of the process!
4) Not performing adequate retest after repairs - Simply replacing the faulted component and seeing that the machine or system starts again is not enough to prevent future downtime or potential safety issues that were created when the fault occurred, or that came to life during the troubleshooting and repair processes. Most maintenance teams could benefit from a much more thorough RETEST regimen after each repair cycle.
Manager Tip – By quizzing your technicians about the retest performed and asking questions along these lines as part of the wrap up for each repair, you can help implant the correct attitudes and approaches to repair work that will have a huge positive impact over time.
5) One last note for Maintenance Management – A problem I often see managers make is to expect their techs to be able to definitively identify the fault in complex electrical, instrumentation, or automation systems just as fast as faults can be identified in some mechanical systems or systems that are easier to understand and digest. The reality is that even the sharpest, most experienced instrument, electrical, or automation technician is likely going to need to do some research sometimes on hard problems (reading ops manuals, vendor manuals, reviewing schematics, diagrams, logic sheets, programming, configs, etc.) and all of this can take time. Sadly, I have seen some managers over the years show no patience for this necessary part of the process and often push too hard for quick ‘wrench-turning’, which often results in part-swapping and other mistakes. When you see a strong tech reviewing manuals or prints, it is probably the right thing to be doing. Just ask them and listen. Most techs can explain why they need to review the references and/or what they are checking. It takes some time to accurately and safely solve many problems. As a maintenance manager, never encourage techs to bypass using logic in hopes of a quick-fix, or encourage them to 'guess' or to 'swap parts' simply so that it 'seems like they are making progress'. I’ve seen many situations where a single manager was able to shift the troubleshooting approach and effectiveness of a whole crew or shop (either in a good direction, or sometimes in bad direction).
Below is a loose example of a typical 7-step troubleshooting method that works well for most industrial facilities. On more complex systems you may have to repeat steps 3 and 4 as you zoom in from the major systems down through sub-systems and so forth. This ‘zooming-in’ approach allows techs to ‘divide and conquer’ even complex systems in a very methodical way and will yield big improvements in most maintenance teams and techs.
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- Symptom Recognition - Thorough analysis and understanding of symptoms and of the reported problem. This stage may include gathering information, reviewing how the system should work, gather maintenance and trouble logs, etc..
- Symptom Elaboration - This stage typically involves various quick-tests and observations such as front panel indications, testing different modes, etc.
- Determine the Faulty Systems - Thinking ‘big-picture’ to identify the potential faulty systems that could cause the problems observed – and then testing to prove parts of the system good (or bad) to narrow in on the problem.
- Determine the Faulty Sub-Systems or Components - Once the problem has been narrowed to a specific system, repeat the process by identifying the potential faulty sub-systems or components that could cause the problems – and testing to prove individual parts good or bad to narrow in on the problem. Depending on system complexity, there may be several ‘zoom-in’ levels in this approach, or just a couple.
- Definitively Prove Fault – Once a suspected fault has been identified (such as with voltage checks), work to PROVE the item is definitively faulty via more thorough checks (such resistance checks for example).
- Identify the Cause of Failure - Determine the root cause of the failure (RCF).
For example: Instead of just swapping out the bad relay or switch, the tech should ponder what may have caused the problem…. Inductive kick from a large dc solenoid will quickly degrade switch or relay contacts unless the surge suppressors are working properly… If you are replacing certain switches or relays repeatedly, check out the suppressors (diode, MOV, etc.) - Repair & Retest – This is another weak spot for many techs and maintenance teams. Often times, the technician only tests the specific function or event that was reported as the failure such as: “This valve won’t open” – but the problem repeats soon afterwards, because the item that was replaced was only a part of the problem, or possibly because another problem was created due to the failure, or was accidentally injected during the troubleshooting process. Retest may include items such as:
- Operational check (in each running mode)
- Calibration or alignment checks if needed
- Safety/Functional tests of applicable system part
Notes:- *The retest requirements can sometimes be of huge safety consequence and/or could prevent huge expensive machine damage. Any time a system has been experienced damage or has been tinkered with, appropriate retest steps should be performed to ensure all important systems and functions are working properly.
- **If anyone replaced any parts, changed any configurations, or made other ‘temporary’ alterations, all of those should be thoroughly reviewed and verified correct prior to running again.
- Symptom Recognition - Thorough analysis and understanding of symptoms and of the reported problem. This stage may include gathering information, reviewing how the system should work, gather maintenance and trouble logs, etc..
In our 4-day, hands-on Basic Electricity and Electrical Troubleshooting Course, we first develop (or solidify) a solid understanding of Basic Electricity, so that techs are truly ready to think ‘electrically’ and then we spend several days building, testing, and then troubleshooting a variety of increasingly complex circuits with an emphasis on the methodology and logic of troubleshooting. The objective of this training course is to produce a measurable improvement in troubleshooting skills.