LG RESU with SolarEdge Error 3x6B: what it means and what to do
On a SolarEdge inverter, "Error 3x6B" means Battery communication error: the inverter has lost communication with the battery, such as an LG Chem RESU, which LG lists as compatible with SolarEdge inverters. SolarEdge's fix is to make sure the RS485 and Enable (En) wires between battery and inverter are connected correctly and that the battery is set up correctly in the inverter.
Fix soon
Common causes
- RS485 communication or Enable wires between the battery and inverter loose or wrongly connected.
- Battery communication settings in the inverter configured incorrectly, for example after an inverter replacement.
- The battery is off or in a fault state and not responding.
Safe steps to try
- Check the battery lights Look at the RESU front panel. If the FAULT light is on, see the LG RESU FAULT light guide.
- Note the error and when it started Photograph the inverter screen or app showing Error 3x6B and note any recent work, such as an inverter replacement.
- Leave the wiring to a technician The RS485 and Enable wires and battery settings are inside the inverter and battery wiring areas. Do not open them yourself.
When to call a professional
Contact your installer or a SolarEdge-qualified technician. They check the communication wiring, battery configuration and firmware on both the inverter and the LG battery.
Frequently asked questions
- Is 3x6B an LG code or a SolarEdge code?
- It is a SolarEdge inverter error. It describes the link to the battery, which on many systems is an LG RESU.
- What is Error 3x6C?
- SolarEdge lists 3x6C as a battery internal error and says to contact SolarEdge support.