This standard specifies the requirements for earthing arrangements, protective conductors, and protective bonding conductors for electrical installations to ensure safety. It covers the selection, erection, and sizing of these components, forming a critical part of the overall safety measures against electric shock and electromagnetic disturbances.
Provides fundamental principles and requirements for the design, erection, and verification of low-voltage electrical installations, based on IEC 60364.
Quick Reference Values
Minimum diameter for solid copper earth rod12.5 mm
Minimum diameter for hot-dip galvanized steel earth rod16 mm
Minimum size of GI strip electrode25 mm x 4 mm
Minimum size of copper PE conductor (mechanically protected)2.5 sq.mm
Minimum size of copper PE conductor (not mechanically protected)4 sq.mm
Use of aluminum as buried earth electrodeNot permitted
Key Formulas
S = sqrt(I²t) / k — Adiabatic equation for calculating minimum cross-section 'S' of a protective conductor
Practical Notes
This code is the Indian adoption of IEC 60364-5-54, so it aligns with international practices for earthing systems.
While the code provides a formula for sizing protective conductors, for most standard installations, the simplified method using Table 54.2 (based on phase conductor size) is sufficient and widely used.
Never use aluminum for buried earth electrodes as it corrodes rapidly in soil (Clause 542.2.1).