Red Seal Electrician Practice
TransformersQuestion 1050 of 1506

What are the drawbacks of a V (open-delta) bank compared with a full delta-delta bank?

  1. It needs three times more windings than a normal bank
  2. It cannot supply any load at all
  3. It requires a neutral conductor on both sides
  4. Both units must be oversized; no fault tolerance
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Correct answer: Both units must be oversized; no fault tolerance

The two units must carry the full power, and if one fails the load is affected.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 7.6: Three-phase Transformer Circuits

Practice transformers

Questions last reviewed: 18 October 2026