ESCL — Electrical Schematic Context Language

A structured text format that makes industrial electrical schematics queryable by AI.

The Problem

Electrical schematics for industrial machines are trapped in PDFs. EPLAN, AutoCAD Electrical, and similar CAD tools export documentation that humans can read—but machines cannot. When a circuit breaker trips at 2 AM, you're flipping through a 200-page PDF trying to trace which components are affected.

ESCL changes this by representing schematics as structured text. Components, connections, potentials, and cross-references become data that an AI can query, trace, and reason about.

What's in this repo

├── ESCL_SPECIFICATION_v1.0.md   # Complete language specification
├── escl-generator-skill.md      # Claude skill for PDF→ESCL conversion
├── escl-query-skill.md          # Claude skill for querying ESCL files
└── extract-pdf.js               # Node.js tool for PDF page extraction

Quick Example

@potential L502 {
  description: "24VDC after E-Stop"
  type: DC
  voltage: 24V
  origin: -K1M =7/1.4
  consumers: [-U1, -A1, -K5]
}

vfd -U1 "SEW Movidrive" {
  model: "MDX61B0110-5A3-4-00"
  power: 11kW
  input {
    L1, L2, L3: <- -Q7 =10/4.1
  }
  output {
    U, V, W: -> -M7 =10/4.8
  }
}

Getting Started

Prerequisites

• Claude environment with file system access (Claude Code, computer use, etc.)
• Node.js (for PDF extraction)

Installation

# Clone the repo
git clone https://github.com/yourusername/escl.git
cd escl

# Install PDF extraction dependencies
npm install

Converting a Schematic

1. Extract PDF pages as images:

   node extract-pdf.js schematic.pdf project/images/ --dpi 150

1. Load the Generator skill into Claude and ask:

   Convert this schematic to ESCL format.

1. The agent processes each page, tracking progress in state.json.

Querying ESCL

Load the Query skill and ask natural language questions:

What feeds motor -M7?
If -Q5 trips, what stops working?
Create a troubleshooting checklist for the conveyor.

Two Claude Skills

Generator Skill (escl-generator-skill.md)

• Converts schematic PDFs to ESCL format
• Extracts pages as images, parses components and connections
• Maintains state file for resumable conversion

Query Skill (escl-query-skill.md)

• Answers questions about ESCL files
• Traces power chains, finds cross-references
• Generates troubleshooting checklists

Documentation

• Full Specification — Complete language reference with grammar
• Project Website — Overview and examples

License

MIT

Contributing

Contributions welcome. Please open an issue to discuss significant changes before submitting a PR.