Industrial Wiring Standards That Even Electricians Don’t Know About

Industrial electrical systems can be complex and dangerous if not installed properly. As an industrial electrician for over 20 years, I've come across wiring standards and best practices that even some experienced electricians are unaware of. In this in-depth guide, I will share key industrial wiring standards to ensure safety and compliance.

Use The Correct Wire Size

Selecting the appropriate wire size is critical in industrial settings. Oversized wires waste money while undersized wires can overheat and cause fires. The National Electrical Code (NEC) specifies wire sizes based on ampacity and voltage drop limits.

Bold key: Always check NEC requirements when selecting wire sizes. Errors can lead to electrical code violations.

Maintain Proper Bending Radii

Sharply bending wires can damage the insulation and cause shorts or fires. NEC Table 312.6(A) lists the minimum bending radii for various wire types and thicknesses.

Underline key: Gradual long radius bends minimize insulation damage in large industrial cables.

Use Strain Relief On Cable Terminations

Industrial environments vibrate constantly from heavy machinery. This vibration can break wire strands and cause loose connections over time.

Proper strain relief techniques prevent excessive vibration or movement of cables and wiring.

Strain relief protects wiring from fatigue and adds years to the system lifespan.

Class 1 Division 2 Wiring In Hazardous Locations

Certain industrial areas contain potentially explosive gases, vapors, or dusts. These hazardous locations require specialized electrical wiring methods to prevent sparks and overheating.

Bold key: Never run unprotected cables in areas that contain hazardous dusts or vapors. Use rigid metal conduit for all wiring.

Balance Single Phase Loads

Three-phase power systems depend on balanced loads across the phases. Uneven loads can cause voltage imbalance and equipment problems.

Table comparing balanced vs unbalanced single phase loads:

| Balanced 3-Phase Loads | Unbalanced 3-Phase Loads |
| Equal current on phases A, B, C | Excess current on phase A |
| 120V between phases | Voltage imbalance |
| Equipment runs cooler | Equipment overheating |

Underline key: Proactively balance single phase loads instead of troubleshooting issues later.

Follow Arc Flash Safety Protocols

Industrial power systems carry high fault currents that can cause dangerous arc flash hazards and explosions. Take these precautions:

Bold key: Arc flashes cause severe burns and even death. Rigorously follow arc flash safety protocols.


Mastering industrial wiring best practices takes years of experience. Reference the NEC frequently, and consult local inspectors whenever in doubt. Though the standards may seem tedious, proper installation technique greatly improves safety and prevents costly downtime from electrical failures. Use this guide as a supplement to your hands-on training and stay up-to-date on the latest code requirements.