1. Transformer Tap Changing (Voltage Regulation)

• Power transformers have tap changers to adjust voltage levels by modifying the turns ratio in the windings.
• Types of Tap Changers:
  • On-Load Tap Changer (OLTC) – Adjusts taps while the transformer is running.
  • Off-Load Tap Changer (OLTC) – Requires shutting down the transformer before adjusting taps.
• Purpose: Maintains stable voltage despite fluctuations in load or input voltage.

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2. Tapping a Transformer for Signal Extraction

• Used in electronic circuits and audio applications to extract different voltage levels.
• Example: Tube amplifiers use transformer taps to provide different impedance levels for speakers.
• Also seen in power supplies, where multiple taps provide different output voltages from a single winding.

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3. Mechanical Tapping on a Transformer (Fault Detection)

• Why Tap a Transformer?
  • To check for loose windings that might cause vibrations.
  • To detect lamination issues causing buzzing sounds.
  • Sometimes used in diagnostics to check for structural integrity.

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4. Neural Network Transformers (AI/ML) – Attention Tapping

• In AI models like GPT, BERT, “tapping” could refer to:
  • Extracting attention weights to understand how a model processes input.
  • Modifying attention layers to improve learning efficiency.
  • Knowledge distillation, where parts of a large transformer model are “tapped” to train smaller models.