Photovoltaic panel string repair

How do I compare solar panel string voltages?

For those much more tech-savvy people, you can compare the solar panel string voltages via the inverter display or wifi app. Solar panels are typically linked together in strings of between 4 and 14 panels and most residential solar inverters have two independent string inputs (often called MPPTs).

How do I fix a damaged PV string circuit?

If you find minor damage on a PV string circuit in free air, you can cut out the damaged wire section. Replace it with a field-installed quick connector like an MC4. Verify that no current is flowing in the circuit using a clamp meter, like the Fluke 325 True-RMS Clamp Meter, 378 Non-Contact AC/DC Clamp Meter, or 393 Solar Clamp Meter.

How do I troubleshoot a solar photovoltaic system?

Troubleshooting a PV solar photovoltaic system will typically focus on four parts of the system: the PV panels, load, inverter, and combiner boxes. The all-around best tool to use for working in most areas of a solar installation is the Fluke 393 FC CAT III 1500 V Solar Clamp Meter .

What if I have a problem with string voltages?

If you think you have a problem with string voltages then you should contact your solar retailer, a solar installer or a solar professional to inspect the system. A simple method using the string (MPPT) readings from a solar inverter to determine if two strings with the same number of solar panels are operating correctly.

What happens if a PV string circuit does not have a ground fault?

A PV string circuit without a ground fault will have open circuit voltage (Voc) between positive and negative conductors. It will have zero volts from positive to ground and from negative to ground. When a ground fault is present, measurement will show Voc between positive and negative conductors.

How do I fix a faulty PV module?

Check the PV wire for chaffing, severing or if the cable has been chewed on by wildlife. Likely you will spot the damage that lead to the fault. Replace the faulty module if necessary then replace the GFDI fuse. The system should now be in working order and can be brought back online. Good luck!