Quick Answer
Ensure your wind turbine is safely grounded by installing a grounding system that meets the 10 milliohms per mile standard, using a minimum of 2/0 AWG grounding wire and 3/8 inch copper grounding rods. Consult local and national electrical codes. Regularly inspect and maintain the grounding system.
Grounding System Requirements
A safe grounding system for wind turbines involves meeting specific electrical standards. The National Electric Code (NEC) Article 250 dictates that grounding systems must provide a path for fault currents to safely flow to the ground. A 10 milliohms per mile standard is recommended for grounding systems, which typically require a minimum of 2/0 AWG grounding wire (7.53 square millimeters) with a maximum resistance of 4.5 milliohms per 100 feet.
Grounding Rod Installation
The grounding rods should be installed at least 8 feet away from any electrical conductors or other grounding systems. A 3/8 inch (9.5 millimeters) copper grounding rod is a good choice for most wind turbines, as it meets the NEC requirement for a minimum 2.5 square inch (16.2 square centimeters) surface area. The grounding rod should extend at least 8 feet below grade to provide a reliable connection to the earth.
Grounding System Testing
Regularly inspect and test the grounding system to ensure it meets electrical standards. Use a ground resistance tester to measure the resistance of the grounding system, and compare it to the recommended 10 milliohms per mile standard. Consult a qualified electrician if you’re unsure about any aspect of the grounding system installation or maintenance.
Find more answers
Browse the full Q&A library by topic, or jump back to the topic this question belongs to.