Solar PV Ground-fault Troubleshooting: Theory, Tools, and Field Application
Learn how to locate, troubleshoot, and safely repair ground faults in both central and string inverter systems using digital multimeters and insulation resistance testers. Whether you’re a technician, electrician, or O&M pro, you’ll walk away ready to find it, fix it, and get the system back online fast. Please reach out with any questions and any inquires regarding group enrollments or in-person training via Contact Us or groundfaults@solartechcollective.com
This class is hosted by Heatspring – click the image below to learn more about pricing, content, and duration.
About the class

The course covers both central and string inverter systems – including configurations with harnesses, combiners, and various types of disconnects. Starting off with a review of grounding and bonding, we cover the fundamentals of inverter topologies (transformer-based vs. transformerless) along with their associated grounding and GFDI systems. By the end of the course, you will have a thorough understanding of how different types of ground faults behave and how to safely troubleshoot them using a digital multimeter and insulation resistance tester.
This engaging class explores ground-fault troubleshooting scenarios and system configurations with field videos, system diagrams, graphics, and lectures. It was developed to meet the SEIA’s 301 O&M Technician Level 2 competencies to ensure technicians and O&M companies can safely and efficiently tackle the most challenging and dangerous faults out there.
Lessons:
- Course Introduction
- Introduction to PV System Grounding and Bonding
- Insulation, Resistance, and Faults
- Testing Insulation Resistance
- Inverter Topologies and DC System Grounding
- Ground-fault Path Scenarios
- Fault Voltage and Insulation Resistance
- Introduction to Ground-fault Troubleshooting
- Troubleshooting Hard Faults
- Troubleshooting Resistive Faults
- Central Inverter Scenarios
- Theory vs. Reality: When the Fault Hits the Fan
- Repairing Ground Faults
Learning Objectives:
- Describe how and why PV systems are bonded and grounded
- Identify qualities and the function of insulation in PV systems
- Describe causes and consequences of faults in PV systems
- Describe how to perform insulation resistance testing (IRT) and analyze test results
- Identify common PV inverter topologies along with associated protective devices and grounding configurations
- Recognize ground-fault current paths and the GFDI functionality for different PV inverter topologies
- Identify best practices and safety considerations for ground fault troubleshooting
- Outline general procedures for troubleshooting hard and resistive ground faults
- Identify how to use a digital multimeter and insulation resistance tester to troubleshoot PV DC ground faults
- Describe considerations and procedures for isolating circuits on string and central inverters during DC ground-fault troubleshooting
- Outline troubleshooting techniques for hard-to-locate ground faults
- Describe considerations and methods for repairing ground faults




