lekkovoolu

Leakage current, or lekkovoolu, is the small electrical current that escapes from live conductors to earth or to other conductors due to imperfect insulation or parasitic paths. It is not the intended load current and can occur in AC or DC systems, often through EMI suppression components or moisture-affected insulation.

Common causes include insulation resistance, capacitive coupling to earth, moisture or contamination, aging, and physical damage. Modern devices may introduce leakage deliberately via input filters (for example, Y-capacitors) to meet electromagnetic compatibility standards, while still limiting harmful levels.

Leakage is measured with specialized testers and is regulated by standards that vary by device class and region. Consumer electronics typically exhibit leakage well under a milliamp under normal operation; higher leakage limits apply to larger appliances and specialized equipment. Medical and other high-safety equipment have stricter limits.

Excessive leakage can pose shock and fire risks, cause nuisance tripping of protective devices, and interfere with sensitive electronics. It also represents energy loss and can degrade efficiency.

Mitigation includes good insulation and grounding, careful layout to minimize capacitive coupling, appropriate use of EMI filters, and regular insulation testing. If unexpected leakage is detected, inspect seals, cables, connectors, and earth continuity.