Addressing Parallel Inverter Grid Port Wiring Faults in Sungrow’s SH15/20/25T Hybrid Solar Inverters
When managing a solar power system that includes multiple Sungrow SH15/20/25T hybrid solar inverters operating in parallel, ensuring the correct installation and configuration of grid port wiring is crucial for efficient and safe operation. A common issue that can arise in such setups is a grid port wiring fault, particularly related to inconsistent phase sequencing across the master and slave inverters. This blog post will guide you through the steps to check and correct phase sequence issues to ensure your Sungrow‘s system operates seamlessly and efficiently.
Understanding Grid Port Wiring Faults
Grid port wiring faults in parallel inverter systems can lead to inefficiencies, potential safety hazards, and operational failures. These faults are often due to incorrect wiring phase sequences, where the phase arrangement of the AC connection at the grid terminal does not match among all inverters in the system.
Key Implications of Wiring Faults:
Inconsistent power delivery across the system.
Potential tripping of safety systems which can lead to system downtime.
Possible damage to inverter components over time.
Step-by-Step Guide to Troubleshoot and Fix Wiring Faults
Step 1: Understand Phase Sequencing
Before you begin troubleshooting, it’s essential to understand what phase sequence is and why it’s important:
Phase Sequence: This refers to the order in which the phases (usually labeled as L1, L2, L3) are connected from the power source to the grid terminal of the inverters. The sequence must be consistent across all inverters to ensure synchronized operation.
Step 2: Inspect the Grid Terminal Connections
To check and correct any phase sequence inconsistencies, follow these steps:
Safety First: Always ensure that all power to the inverters is turned off before beginning any inspection or modification to the wiring.
Access the Grid Terminal: Open the access panel to the grid terminal connections on each inverter.
Verify Phase Sequence: Use a phase sequence meter to check the phase sequence at the grid terminal of the master inverter. Repeat the measurement for each slave inverter.
Compare Results: Ensure that the phase sequence matches across all inverters. The most common configuration should be either L1, L2, L3 or L3, L2, L1 consistently across all units.
Step 3: Correct Any Inconsistencies
If you find any discrepancies in the phase sequence:
Adjust the Wiring: Change the wiring at the grid terminals to match the master inverter’s phase sequence. This might involve swapping two of the phase wires.
Document Changes: Keep a record of any changes made for future maintenance and troubleshooting.
Step 4: Test the System
After adjusting the wiring:
Re-energize the System: Turn the power back on.
Monitor the Operation: Check the system’s operational status through the inverter’s display or monitoring software. Look for any immediate fault indicators.
Observe Over Time: Monitor the system over a few days to ensure no new issues arise and that the system is performing optimally.
Conclusion
Correcting a grid port wiring fault in parallel Sungrow SH15/20/25T hybrid solar inverters is crucial for maintaining the safety and efficiency of your solar power system. By ensuring that all inverters are correctly phased and synchronized, you can prevent operational issues and promote a long lifespan for your installation. Regular checks and maintenance of your system’s wiring and configurations can help catch and resolve these issues before they lead to more significant problems. If you are unsure about performing these checks yourself, it’s advisable to contact a professional technician who can ensure that all connections and configurations are correctly set up and maintained.
