IS 6307:2018 is the Indian Standard (BIS) for porcelain insulators for overhead power lines. IS 6307 specifies porcelain insulators used on overhead power lines for both transmission (HT) and distribution (LT). Covers disc/suspension type for HT lines and pin type for LT lines.
Specification for porcelain insulators (disc, pin, and post type) for overhead power transmission and distribution lines.
Overview
Status Current
Usage level Specialized
Domain MEP — Electrical Installations
Type Specification International equivalents
Also on InfraLens for IS 6307
Practical Notes
! Disc insulators are strung in series — more discs = higher voltage rating. 11kV needs 1 disc, 33kV needs 3, 132kV needs 9.
! Damaged or cracked insulators must be replaced immediately — they can cause flashover and line faults.
! Always test insulators before installation — reject any with visible cracks, chips, or uneven glaze.
Frequently referenced clauses
Cl. 3 — Types: disc, pin, and post insulators
Cl. 4 — Electrical requirements (flashover, puncture voltage)
Cl. 5 — Mechanical requirements (failing load)
Cl. 6 — Thermal shock and porosity tests
porcelain insulator overhead line power line disc insulator electrical insulator
International Equivalents Similar International Standards
IEC 60383-1 IEC
High Current
Insulators for overhead lines with a nominal voltage above 1000V — Part 1: Ceramic or glass insulator units
Both cover ceramic/porcelain insulators for overhead lines with electrical and mechanical requirements.
Key Differences
≠ IEC 60383 covers both ceramic and glass. IS 6307 focuses on porcelain.
Key Similarities
≈ Electrical flashover and mechanical failing load tests are aligned with IEC methods.
Parameter Comparison
Parameter IS Value International Source
⚠ Verify details from original standards before use Report Error
Key Values3 Quick Reference Values
Disc insulator flashover (dry) Min 80 kV
Disc insulator flashover (wet) Min 50 kV
Mechanical failing load Min 70 kN (standard disc)
Tables & Referenced Sections Key Tables
Table 1 — Electrical characteristics by type and rating
Table 2 — Mechanical failing loads
Frequently Asked Questions1 How many disc insulators are needed for different voltages? + Approximately: 11kV=1 disc, 33kV=3, 66kV=5, 132kV=9, 220kV=14, 400kV=22 discs in a string. Exact numbers depend on pollution level.
QA/QC Inspection Templates 📋
QA/QC templates coming soon for this code.