The ground wire is one of the most important safety features in any electrical system — the invisible protector that carries dangerous fault current safely into the earth. This guide explains what grounding is, the standards it must meet, how it’s installed, and the common mistakes to avoid.
What Is a Ground Wire?
A grounding system connects electrical equipment and metal structures to the earth, so that leakage and fault currents can discharge safely into the ground. This protects people from electric shock and helps prevent fire.
Grounding Safety Standards
- Ground resistance of ≤ 5 ohms for typical buildings.
- ≤ 1 ohm for high-security facilities.
- Ground rods buried at least 2.4 meters deep.
- All materials must meet the Thai standard (TIS).
Installation Best Practices
Proper grounding installation follows clear steps: survey the site, drive the rod to the correct depth, make secure connections, and test the ground resistance before putting the system into use.
Common Installation Errors
- Excessive ground resistance.
- Substandard materials or undersized wire.
- Loose connection points.
- No inspection access points.
- Improper system segregation in industrial settings.
Grounding by Building Type
- Residential: single- or dual-rod systems with basic protection.
- Condominiums: multi-point grid systems for comprehensive coverage.
- Industrial: complex multi-point systems with segregated circuits for machinery.
Always engage qualified electricians and use certified equipment for long-term safety and compliance.
Build a Safe Ground System with TETA Intertrade
TETA Intertrade supplies TIS-standard copper-bonded ground rods, grounding wire, clamps, and accessories for residential, commercial, and industrial systems. We help you build a grounding system that meets the resistance and depth standards — for real, reliable protection.
Frequently Asked Questions (FAQs)
What ground resistance is acceptable?
≤ 5 ohms for typical buildings, and ≤ 1 ohm for high-security facilities. Lower resistance means fault current discharges to earth more effectively.
How deep should a ground rod be?
At least 2.4 meters deep, using TIS-standard materials, so the rod reaches moist soil that conducts to earth reliably.
What are the most common grounding mistakes?
Excessive ground resistance, substandard or undersized wire, loose connections, no inspection access, and — in industry — failing to properly segregate circuits.
Does the grounding system differ by building type?
Yes. Homes typically use single- or dual-rod systems, condominiums use multi-point grids for full coverage, and industrial facilities use complex multi-point systems with segregated circuits for machinery.
