Linear and SPE Sag Tension Calculator

Byjaredcuchapin@gmail.com July 4, 2026July 4, 2026

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Notice: For educational and reference use only. Results must be independently verified by a licensed engineer before use in any design or construction. This site accepts no liability for errors or consequences arising from use of this tool.

Calculation Model

SPE applies a fixed permanent-elongation value (PC) directly, in microstrain. LE instead applies an equivalent temperature shift (Δt) — because LE's stress-strain relationship is purely linear, shifting the reference temperature by Δt produces the same strain offset a directly-specified PC would, via the conductor's composite thermal expansion coefficient. Same physical effect (permanent creep elongation), two equivalent parameterizations.

SPE — Simplified Plastic Elongation LE — Linear Elongation

Plastic Elongation PC (µε)

Typical value for ACSR: 600 µε (CIGRE TB 324 §6.2).

Creep Temp Shift Δt (°C)

Equivalent temperature shift for creep (PLS-CADD §9.1). Typical 15–20°C for ACSR.

Conductor Library

Preset values are representative/typical for the conductor family shown — always verify against manufacturer or CIGRE TB 324 tables for your exact conductor size before use in design. Selecting a preset auto-fills all fields below, including the conductor type toggle.

Bimetallic (ACSR) Homogeneous (AAC / AAAC / Copper)

Conductor Properties — Drake 795 kcmil 26/7 ACSR

Area A (mm²)

Unit Weight w₀ (N/m)

Diameter D (mm)

RTS (N)

EFO — area-weighted (MPa/100)

αO — area-weighted (%/°C)

EFC (MPa/100)

αC (%/°C)

T_REF (°C)

ρ_ice (N/m³)

Wind drag Cd

Span & Stringing

Span S (m)

Sagging H₀ (N)

Sagging T₀ (°C)

Weather Cases

Under column PCP, check the weather cases to be included in the final after-load evaluation.

#	Description	T°C	Ice cm	Wind Pa	k (N/m)	PCP
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📐

Configure inputs and press Calculate

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