Why does neutral on secondary sides have leakage of power?

Why does neutral on secondary sides have leakage of power?

Several factors can contribute to power leakage on the neutral side of a secondary circuit in electrical systems:

System Imbalance

If the loads connected to the phases are not balanced, the neutral will carry the imbalanced current. This can induce a voltage drop across the neutral wire, resulting in power leakage.

Grounding Issues

Inadequate grounding or high-resistance connections can generate a potential difference between neutral and ground, leading to leakage currents.

Multiple grounding sites can form ground loops, in which variances in ground potential induce unwanted currents to flow via the neutral wire.

Capacitive Coupling

Capacitance between neutral wire and adjacent live wires might cause leakage currents. This is especially important in lengthy cable runs or in settings with severe electromagnetic interference (EMI).


Non-linear loads, such as computers, LED lights, & variable frequency drives (VFD), generate harmonics. Harmonic currents can travel back through the neutral wire, resulting in power leakage.

Insulation Degradation

Aging (or) damaged insulation on wires can cause leakage currents between live and neutral conductors.

Wiring Errors

Improper connections (or) reversed polarity might result in leakage currents in the neutral wire.

Inductive Coupling

Magnetic fields from nearby conductors may induce currents in the neutral wire, leading to power leakage.

Faulty Equipment

Equipment malfunctions can cause current to flow to the neutral, particularly if internal insulation fails (or) components degrade.

Mitigating Power Leakage in Neutral

System Balance

To decrease neutral current, ensure that loads are balanced across all phases.

Proper Grounding

Verify and upgrade grounding systems to ensure low resistance connections and the elimination of ground loops.

Use of Filters

Install harmonic filters to mitigate the effects of nonlinear loads & harmonics on the neutral wire.

Regular Maintenance

Conduct frequent inspections & maintenance on insulation & wiring to prevent deterioration and spot failures early.

Correct Installation

To eliminate wiring faults and potential leakage channels, use good installation procedures and follow electrical codes.

Understanding and resolving these aspects allows you to reduce power leakage on the neutral side while also improving the overall efficiency & safety of your electrical system.