The production plant is at a standstill. The digital displays of the control system remain dark while the costs of the standstill tick away in the background. This is a situation that occurs time and again in industrial companies - and often the frantic search for the fault in the complex electrical system begins.
The difference between wandering around for hours and targeted problem solving? The right methods for troubleshooting in the circuit diagram.
The three biggest pitfalls in circuit diagram troubleshooting
Why do even experienced technicians sometimes fail to solve supposedly simple electrical problems?
- Blind actionism instead of a system
The impulse to do something immediately is great. But without a methodical approach, troubleshooting is often dramatically prolonged. - Missing or outdated documentation
How often has a system been modified without updating the circuit diagrams? The reality does not always correspond to the documentation. - Assumptions instead of measurements
"That must be it" - this thought has already steered many searches for errors in the wrong direction. Professionals rely on measurements, not assumptions.
From the outside in or from the inside out?
Professional troubleshooters follow established strategies:
The outside-in method
Starting with the overall function of the system, the functional area in which the fault must be located is systematically narrowed down. Ideal for complex systems with many subsystems.
The inside-out method
Based on known, specific symptoms, linked components and functions are checked in a targeted manner. Efficient for clearly localizable fault patterns.
How do beginners differ from professionals?
If you observe experts during troubleshooting, you will notice typical patterns of behavior:
Beginner's approach:
- Jumping between different assumptions
- Repeated checking of the same points
- Concentration on obvious components
Professional method:
- Systematic limitation of the error range
- Continuous documentation of the test steps
- Use of the circuit diagram structure as a navigation aid
- Consistent exclusion of functioning areas
The SPLIT method: The turbo for troubleshooting
The SPLIT method is a particularly efficient technique:
System overview PIdentify checkpoints Logic division of the search area Isolation of the faulty area Testen of the hypothesis
This method uses the binary search principle: In each step, the area to be examined is halved, which reduces the necessary test steps exponentially.
In a real case, a production plant was able to reduce the average troubleshooting time by 64% by consistently applying the SPLIT method - a considerable economic factor.
Digital tools as game changers
Modern CAE systems such as EPLAN offer functions that revolutionize troubleshooting:
- Global search functions for components and connections
- Navigation aids through cross-references
- Emphasizing functional relationships
- Dynamic filtering according to voltage levels or signal types
The practical checklist for systematic troubleshooting
- Error analysis: What symptoms are there and when do they occur?
- Interface check: Are the inputs and outputs of the affected system functioning?
- Power supply check: Are all the necessary voltages present?
- Systematic signal tracing through the circuit diagram
- Documentation of all test steps and measurement results
Systematic troubleshooting in the circuit diagram is not an innate skill, but a method that can be learned. With the right approach and modern tools, even complex problems can be solved efficiently - and expensive downtimes minimized.