ohmly 0.0.17

An electrical and mechanical analysis tool of overhead conductors.

ohmly - An electrical and mechanical analysis tool of overhead conductors

Ohmly is a lightweight Python library for engineers who work with overhead transmission and distribution lines.

It provides the core mechanical tools needed to evaluate conductor behavior under real-world loading conditions: sag, tension, wind, ice, temperature, variation, and more.

The library includes:

• A built-in database of conductor properties.
• Catenary-based sag-tension calculations.
• Multiple load-case (hypothesis evaluation).
• Temperature-dependent tension models.
• Wind & ice loading.

[!IMPORTANT] All mechanical calculations currently follow Spanish ITC-LAT 07 only. Other regulations are not yet implemented.

[!WARNING] Electrical analysis modules will be added in future releases.

Disclaimer

Ohmly is an MIT-licensed engineering support tool.

Mechanical calculations currently follow Spanish ITC-LAT 07 only and must be validated by a qualified engineer.

See DISCLAIMER.md for full details.

Why Use Ohmly?

• Fast and lightweight: Designed for quick analysis without heavy dependencies.
• Regulation-aware: All mechanical calculations follow ITC-LAT 07, ensuring compliance.
• Flexible scenarios: Easily define custom hypotheses, spans, and environmental conditions.
• Clear results: Sag-tension tables are easy to read and integrate into reports.

Documentation

Comprehensive documentation, tutorials, and normative explanations are available in the project documentation.

The docs cover:

• Mechanical analysis workflow (ITC-LAT 07)
• Conductor definition (database and manual)
• Mechanical analysis zones
• Wind, ice, and apparent load calculations
• Hypothesis definition and validation
• Sag–tension tables and controlling hypotheses

📘 Read the full documentation here:
https://ohmly.readthedocs.io/en/stable/

Installation

pip install ohmly

Getting Started

Here's a minimal example that shows how fast it is to compute sag-tension results.

from ohmly import ConductorRepository, MechAnalysis, MechAnalysisZone, MechAnalysisHypothesis

# 1. Load a conductor from the internal database
repo = ConductorRepository()
conductor = repo.get(legacy_code="LA 180")

# 2. Create a mechanical analysis context for zone A
mech = MechAnalysis(conductor, MechAnalysisZone.A)

# 3. Define hypotheses (scenarios) to evaluate
eds = MechAnalysisHypothesis(name="EDS", temp=15, rts_factor=0.15)  # Every-Day Stress
chs = MechAnalysisHypothesis(name="CHS", temp=-5, rts_factor=0.2)   # Cold-Hour Stress

hypos = [eds, chs]

# 4. Define span lengths (in meters)
spans = [100, 200, 300]

# 5. Compute sag-tension table
sagten_table = mech.stt(hypos, spans)

# 6. Print results
print(sagten_table)

Sample output:

                EDS                 CHS
  Span   T (daN), RTS (%)     T (daN), RTS (%)
 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
   100   930.8383, 14.3338   1298.8000, 20.0000
   200   974.1000, 15.0000   1160.4121, 17.8690
   300   974.1000, 15.0000   1067.9360, 16.4450

For a complete, regulation-aligned explanation of each step, see the Mechanical Analysis documentation.

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Project Structure

• ohmly/ – Core library code
• docs/ – Mechanical analysis documentation and tutorials (ITC-LAT 07)