CNG Compressor Electrical & Control System

Project Overview

This project documents the electrical power, control, and safety systems for a Compressed Natural Gas (CNG) compressor installation within a covered parking structure. The facility required hazardous location–compliant electrical installations per NEC Article 500/501 (Class I, Division 2) due to the presence of flammable gas in the vicinity of the compressor equipment.

The safety system is centered on an Emergency Stop (E-Stop) network that allows any authorized personnel to shut down the compressor immediately from multiple locations. Integrated gas detection sensors — monitoring both hydrocarbon (CH₄/CNG) and carbon monoxide (CO) concentrations — trigger multi-zone horn and strobe alarm systems upon threshold breach. The compressor disconnect switch and control enclosures are rated for explosion-proof (XP) installations, and shielded control cables are used throughout the system to minimize interference with gas detection signal integrity. The documentation package includes a floor plan, riser diagram, and detailed installation sheets.

Technical Scope

• ✓Electrical power feed and distribution to CNG compressor
• ✓Emergency Stop (E-Stop) system at multiple locations
• ✓Hydrocarbon (CH₄/CNG) gas detection sensors and monitoring
• ✓Carbon monoxide (CO) gas detection and alarm
• ✓Horn and strobe alarm devices — multi-zone coverage
• ✓Explosion-proof (XP) rated enclosures and disconnect switch
• ✓Shielded control cable wiring for signal integrity
• ✓NEC Class I, Division 2 hazardous location compliance
• ✓Floor plan showing equipment layout and sensor placement
• ✓System riser diagram and electrical detail sheets