When a dry-type transformer malfunctions, scientific approaches are needed for troubleshooting.

Start by observing the symptoms: check whether the transformer shows cracks, unusual noises, odors, overheating, or other abnormal signs. Then, use appropriate instruments for testing, analysis, and diagnosis. Combine these with other troubleshooting methods and techniques to accurately identify and resolve the issue.

Here are the “Ten Methods” for reference. These apply not only to transformers but to all electrical equipment:

Ask: Question the operators or maintenance staff about the conditions before the fault occurred—such as overload, unusual sounds, sparks, etc.—to get a general idea.

Look: Visually inspect the external condition and operation of the equipment. Compare with circuit diagrams and relevant documentation for analysis.

Listen: Pay attention to operating sounds, such as relay engagement, inductors, transformers, or contactors humming or squealing.

Smell: Detect any burnt odor that may result from overheating or short circuits.

Touch-check: Safely touch key parts of the equipment to assess temperature, component looseness, or vibration.

Disconnect: Gradually disconnect sections of the circuit to narrow down the fault location.

Short-circuit: Temporarily short switches, signals, or parts of the circuit to isolate the faulty section.

Restart: Power the equipment off and on again; sometimes the fault alarm may clear.

Replace: Swap in a known good component to see if the fault disappears.

Test: Use instruments to measure electrical parameters and compare them with normal values to analyze the cause.

These ten methods are applied in a logical order: from simple to complex, dynamic checks before static, power supply before load, human factors before system issues, and external inspection before internal. This approach helps reduce unnecessary disassembly and testing while ensuring reliable connections across circuit boards, components, and cable terminals.

Have you learned these steps?