Substation Main Earthing Conductor Strip Sizing Tool
Computes adiabatic short-circuit thermal withstand cross-section for Galvanized Iron (GI), Bare Copper, and Aluminum conductor flats per IS 3043:2018 Clause 12.2.2.1 and IEEE Std 80.
Governing Standards & Source Table Attribution
Standards & Source Constants
- IS 3043: 2018 (Second Revision): Code of Practice for Earthing:
- Clause 12.2.2.1: Conductor thermal withstand equation ($S = I_{\text{sc}} \sqrt{t} / K$).
- Table 6A & Table 6B: Material constants: GI ($K=80$ for bolted joints, up to $500^\circ\text{C}$ welded); Copper ($K=205$ welded, $198$ bolted); Aluminum ($K=126$).
- IEEE Std 80-2013: IEEE Guide for Safety in AC Substation Grounding (Clause 11.3 & Table 1).
- Corrosion Allowance Status: Formally designated as Project / Design Soil Corrosion Allowances — Configurable Engineering Assumptions based on site soil resistivity and chemical aggressiveness.
Commercial Flat Sizing Schedule
S_design = S_theor × (1 + %Corrosion / 100)
Standard commercial flats evaluated: 25×3 (75 mm²), 25×6 (150 mm²), 32×6 (192 mm²), 40×6 (240 mm²), 50×6 (300 mm²), 50×8 (400 mm²), 65×8 (520 mm²), 75×8 (600 mm²), 75×10 (750 mm²), 80×10 (800 mm²), 100×10 (1000 mm²).
This tool designs strictly the thermal short-circuit cross-section of the conductor strip. It does NOT validate substation touch potential ($E_{\text{touch}}$), step potential ($E_{\text{step}}$), Ground Potential Rise (GPR), mesh voltage, or earth grid resistance ($R_g$). Complete substation earthing design mandates a Wenner 4-point soil resistivity survey and IEEE 80 / IS 3043 grid design verified by a Chartered Engineer.