3x6D on a SolarEdge HD-Wave single-phase inverter: Internal RGM Error: Internal RGM (revenue-grade meter) error - check the Energy Meter CTs wiring
Short answer
On a SolarEdge inverter, 3x6D means: Internal RGM Error: Internal RGM (revenue-grade meter) error - check the Energy Meter CTs wiring. The inverter keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: Internal RGM Error: Internal RGM (revenue-grade meter) error - check the Energy Meter CTs wiring.
Part involved: Energy meter / CT clamp communication.
Likely causes:
- CT wiring fault/orientation.
Is it safe?
| Does the inverter stop? | Partly |
|---|---|
| Severity | Warning |
| Engineer needed? | Yes |
The inverter keeps running with some functions stopped.
Resetting itself: yes - clears when communication is restored.
Manual reset: no.
What you can check
- Read and note the exact code and time from the inverter display or app (screenshot).
- Check the meter's display is lit (look only).
- Note any recent electrical work near the meter/consumer unit.
- If the code persists, contact the installer. SolarEdge's list says 'OFF/ON to reconnect' for some codes - that means the inverter's own ON/OFF switch; only use it if your installer has shown you how. Never open the inverter or touch DC cables/connectors.
What the engineer will check
- Check meter RS485/Modbus wiring polarity and termination.
- Check CT orientation (arrow towards grid/house per manual) and seating.
- Check meter address/baud settings.
- Check export-limit setting (G99) - some inverters stop if export control is on and meter lost.
Who to ask for: PV/battery installer.
Certification: Installer or electrician for meter/CT/comms cabling; homeowner can handle Wi-Fi/router issues.
What you might notice
Sources
- Troubleshooting SolarEdge Systems, Addendum (Europe & APAC) MAN-01-00333-1.2 ↗ · MAN-01-00333-1.2 · page PDF p.5 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026