Victron SolarEdge AC Coupling: APS Mode Setup & Troubleshooting

Key Takeaways

• The Factor 1.0 rule is a critical sizing guideline that must be adhered to for stable AC coupled systems.
• SolarEdge HDwave inverters are required, specifically 3phase and 1phase models.
• Specific firmware versions (4.8.24 for SetApp or 3.25xx for LCD inverters) are essential for APS mode functionality.
• US models of SolarEdge inverters are not compatible due to a lack of frequency control.

Why is my Victron system not AC coupling with SolarEdge in APS mode?

The most common reasons for issues with Victron and SolarEdge AC coupling in APS mode are incompatible SolarEdge inverter models, outdated firmware, or incorrect system sizing. The first step is to verify your SolarEdge inverter is an HDwave model and has the required firmware version.

Diagnosis

Follow these steps to diagnose common issues preventing proper APS mode operation with your Victron and SolarEdge AC coupled system.

1. Check SolarEdge Inverter Model Compatibility.

• • Observation: Identify the model of your SolarEdge inverter.
  • Meaning: APS mode is only available for 3phase and 1phase HDwave inverters. If your inverter is not an HDwave model, it will not support this feature.

2. Verify SolarEdge Inverter Firmware Version.

• • Observation: Check the firmware version installed on your SolarEdge inverter.
  • Meaning: For SetApp (screenless) inverters, Firmware 4.8.24 or higher is required. For LCD inverters, Firmware 3.25xx or higher is needed. Older firmware versions will prevent APS mode from functioning.

3. Confirm Regional Model Compatibility.

• • Observation: Determine if your SolarEdge inverter is a US model.
  • Meaning: US models currently lack Frequency Control, and are therefore not compatible with Victron AC coupling in APS mode.

4. Review System Sizing Against Factor 1.0 Rule.

• • Observation: Compare your total AC coupled PV power to your Victron inverter/charger's rated power.
  • Meaning: The AC coupled system sizing guideline, Factor 1.0 rule, from Victron Energy for AC coupled system must be adhered to. Failure to follow this rule can lead to instability and unexpected shutdowns.

5. Inspect Grid Sensing Configuration.

• • Observation: Check if a dry-contact is installed and properly connected for sensing the grid supply.
  • Meaning: A dry-contact for sensing the grid supply is required for APS mode operation. Victron's auxiliary Dry-Out can also be used for this purpose.

6. Check for SolarEdge Grid Meter (if Zero Feedback is desired).

• • Observation: If your system is configured for Zero feedback, verify the presence and proper installation of a SolarEdge grid meter.
  • Meaning: A SolarEdge grid meter is required for Zero feedback functionality in an APS mode setup.

Cause/fix table

AC Coupling Requirements and Configuration

Successful APS mode operation relies on meeting specific hardware and software requirements. This mode allows for extended frequency and voltage operating ranges, crucial for off-grid applications.

Inverter Compatibility: Only 3phase and 1phase HDwave SolarEdge inverters support the APS feature. Older or non-HDwave models will not function correctly in this setup.

Firmware Versions: Ensure your SolarEdge inverter has the necessary firmware. For SetApp (screenless) inverters, Firmware 4.8.24 or higher is mandatory. LCD inverters require Firmware 3.25xx or higher. Always check for the latest stable firmware releases from SolarEdge.

Sizing Guidelines: The Factor 1.0 rule is a critical sizing guideline from Victron Energy for AC coupled systems. This rule dictates the maximum AC PV power relative to the Victron inverter/charger's capacity to ensure system stability and prevent overloads. Adherence to this rule is essential for reliable operation.

Grid Sensing: A dry-contact is required for sensing the grid supply. This can be a dedicated dry contact relay or Victron's auxiliary Dry-Out output, configured to signal grid presence. This input informs the Victron system about the grid status, enabling proper APS mode functionality.

Zero Feedback Configuration: If your installation requires Zero feedback to the grid, a SolarEdge grid meter must be installed. This meter accurately measures energy flow, allowing the system to prevent excess solar power from being exported to the utility grid.

Safety: Electrical Hazards

Working with solar power systems involves high voltages and currents that can be lethal. Always prioritize safety. Disconnect all power sources—PV, battery, and AC grid—before performing any physical checks or wiring. Use insulated tools and follow lockout/tagout procedures. A spanner across a battery bank can short hundreds of amps, causing severe burns or explosions.

When to call a technician instead

If you are unsure about any of the diagnostic steps, lack the necessary tools, or are uncomfortable working with high-voltage electrical systems, contact a qualified solar technician. Incorrect wiring or configuration can damage equipment, void warranties, and create dangerous conditions. Specifically, if your SolarEdge inverter is not an HDwave model or is a US model, professional advice may be needed for alternative solutions as these units are fundamentally incompatible with APS mode AC coupling.