TRANSMISSION LINE ENGINEERING · PRO BETA

Transmission Line SAG Calculator

Try Catenary PRO beta for full transmission-line sag, tension, temperature and environmental analysis, or switch to the free quick sag check.

IEC 60826 workflowEN 50341-1 workflowSag & tensionRuling spanWind & iceStringing chart

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CHOOSE WORKFLOWQuick field check or full line engineering.

FREE · QUICK SAG CHECK

Transmission Line Sag Calculator

A fast level-span estimate using the standard shallow-sag parabolic relationship. No account required.

FREE

Calculation Span length L m Conductor weight kg/m or N/m

Horizontal tension H kNKnown horizontal component of conductor tension. Attachment height m · optionalUsed only for the approximate midspan clearance result.

LEVEL SPANf = —

optional attachment height

Midspan sag—

Horizontal tension—

Support tension—

Sag / span—

Approx. conductor length—

Approx. clearance—

PARABOLIC APPROXIMATION · SHALLOW SAG

Quick level-span estimate under uniform vertical self-weight.

f = wL² / 8H

Catenary PRO v1.2 beta

Overhead transmission-line engineering · IEC 60826 / EN 50341-1 workflow · beta

EN 50341-1 IEC 60826 PRO PREVIEW

Quick conductor presets

Load scenario

Engineering beta. The calculation engine runs server-side. This beta is still being validated. Independently verify inputs, outputs, standards, conductor data and project requirements before engineering release or construction use.

Geometric visualization

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EDS sag— Horizontal tension (H)— Thermal sag— Clearance—

Current state

Maximum sag (Tmax + creep)

Minimum sag (Tmin)

Ground level

Geometry and state analysis

↓ EDS sag

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⟷ Ruling-span tension

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◎ Lowest-point position

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⌘ Catenary parameter (a)

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↕ Sag at Tmax

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Δf = 0.000 m

≋ Actual conductor length

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Extension vs span: — Additional sag from creep: — Total maximum sag: —

Mechanical stress — current state

↑ Stress at point A — lower support

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↑ Stress at point B — higher support

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⇩ Vertical force — upper support

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⇩ Vertical force — lower support

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🛡 Safety factor

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% MBS utilization

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State-change schedule

Condition	Temperature (°C)	Load (N/m)	σA (MPa)	σB (MPa)	Sag f (m)	Status

Stringing chart

No wind, no ice

Temperature (°C)	Sag f (m)	Horizontal tension H (N)	Support tension U (N)	Parameter a (m)

Load and environment summary

Gravity load

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w · g

Ice load

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Radiálny ľad

Wind load

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Na priemer s ľadom

Resultant load q

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N/m

Swing angle

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Odfúknutie vetrom °

Air density

—

kg/m³ podľa n.m.v.

Checks and status

Design parameters

Span geometry

Actual span L m

Ruling span Lrs LRS = L

Support height difference ΔH m

Attachment height m

Minimum clearance m

Span Type

Conductor properties

Bundle conductors n ks

Conductor diameter d mm

Unit mass w kg/m

Metallic area mm²

Minimum breaking strength N

Elastic modulus E GPa

Thermal expansion α ×10⁻⁶/K

EDS baseline and installation

Auto-EDS

Tension limit % MBS

EDS stress σ0 MPa

EDS utilization—

EDS temperature T0 °C

Installation temperature °C

Temperature conditions

Maximum conductor temperature °C

Minimum design temperature °C

Current scenario temperature °C

Environmental loads

Return-period factor

Wind speed m/s

Terrain category

Drag Coeff (Cd)

Radial ice thickness mm

Ice density kg/m³

Altitude m n.m.

Wind Dir. °

Drsnosť terénu z₀ m

Námrazová oblasť EN 50341

Gq=— | Gc=— | Kh=— | qw=— N/m

Creep rate %/dec

Service life rok

Current A

Resistance Ω/km

Safety factor (γ)

EDS limit %