If the defective equipment is part of an assembly line, the whole assembly line could be down causing unexpected 'time off' and lost revenue. If you are at a customer site to repair equipment, the customer may watch you, knowing that they are paying for every minute you spend troubleshooting and repairing their equipment. Either one of these scenarios - and there are more, can put a lot of pressure on you to solve the problem quickly.
So what is troubleshooting? It is the process of analyzing the behavior or operation of a faulty circuit to determine what is wrong with the circuit. It then involves identifying the defective component(s) and repairing the circuit.
Depending on the type of equipment, troubleshooting can be a very challenging task. Sometimes problems are easily diagnosed and the problem component easily visible. Other times the symptoms as well as the faulty component can be difficult to diagnose. A defective relay with visual signs of burning should be easy to spot, whereas an intermittent problem caused by a high resistance connection can be much more difficult to find.
What makes an expert Troubleshooter? One trait of expert troubleshooters is that they are able to find virtually any fault in a reasonable amount of time. Easy faults, complicated faults, they find them all. Another trait is that they typically replace only the components that are defective. They seem to have a knack for finding out exactly what is wrong. No trial and error here. So what is their secret?
You might think that a person, who has a very good understanding of how the equipment works, should be able to troubleshoot it effectively. Being a good at troubleshooting requires more than this.
Expert troubleshooters have a good understanding of the operation of electrical components that are used in circuits they are familiar with, and even ones they are not. They use a system or approach that allows them to logically and systematically analyze a circuit and determine exactly what is wrong. They also understand and effectively use tools such as prints, diagrams and test instruments to identify defective components.
Finally, they have had the opportunity to develop and refine their troubleshooting skills.
If you want to troubleshoot like the pros you will need to develop your skills in each of these areas. Let's look at them in more detail.
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Understand how the circuit works. This consists of understanding the operation of all the components that are used in the circuit. This could include such components as: push buttons, contactors, various types of switches, relays, sensors, motors, etc. Electrical circuits typically control or operate mechanical systems and components. You also need to understand how these mechanical aspects of the equipment operate to carry out the work.
You need to be able to determine how the circuit works under normal conditions and what effect changing one of the circuit inputs has on the circuit operation. For example, what happens to the overall circuit operation when a push button is pressed; which relays energize, which lights illuminate, does the pump start or stop, etc.
You also need to be able to determine what effect a faulty component may have on the circuit operation.
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Use a logical, systematic approach to analyze the circuit's behavior. This is critical. There are several approaches that troubleshooters use. They may have different steps or processes but they have the following in common: They all approach problems systematically and logically thus minimizing the steps and ruling out trial and error. One such approach used to teach troubleshooting is called the '5 Step Approach'.
A summary of the key steps are:
Observe Most faults provide clues as to their cause. There could be visual clues such as signs of damage or improper operation. Don't forget to use your other senses; sounds and smells can also provide valuable clues.
Through careful observation and some reasoning, most faults can be identified to the actual component with very little testing. Define problem area at this stage you apply logic and reasoning to your observations to determine the problem area of the malfunctioning equipment. Identify Possible Causes Once you have the problem area(s) defined it is necessary to identify all the possible causes of the malfunction.
Determine most probable cause once the list of possible causes has been made it is necessary to prioritize the items as to the possibility of them being the actual cause of the malfunction. Test and Repair Once you have determined the most probable cause, you must test it to prove it to be the problem or not.
See A Systematic Approach to Troubleshooting for more details on this approach.
