Definition Check: What Constitutes a Balanced Load? Evaluate the statement: “A balanced load is one in which all the impedances are equal.”

Introduction / Context:
Balance in three-phase systems simplifies analysis and maximizes efficiency. Recognizing the definition of a balanced load is foundational for applying per-phase equivalents and for predicting neutral currents and phase voltages accurately.

Given Data / Assumptions:

• Three-phase system (Y or Δ), sinusoidal steady state.
• Per-phase impedances considered at the same frequency.
• Line impedances are neglected for the core definition.

Concept / Approach:

A load is balanced if the three impedances are equal in magnitude and phase angle (i.e., identical complex impedances). This ensures equal phase currents (for Y) or equal branch currents (for Δ) separated by 120° and results in symmetrical voltages and currents across phases.

Step-by-Step Solution:

Verification / Alternative check:

Measure phase currents in a practical setup; equal magnitudes and 120° spacing confirm balance. Network analyzers or phasor calculations reaffirm that equal complex impedances create symmetrical currents.

Why Other Options Are Wrong:

Limiting balance to Δ or Y only is incorrect; balance applies in either connection. Power factor does not need to be unity; the impedances may be inductive or capacitive as long as all three are identical.

Common Pitfalls:

Assuming “equal magnitude only” is enough; the phase angle must also match. Different angles yield unbalanced reactive power even if magnitudes are equal.

Final Answer:

True