Victron Inverter Compatibility with LG Chem RESU Batteries

Key Takeaways

• LG Chem RESU battery models are End-of-Life and no longer supported by LG.
• A Victron GX device (Color Control GX or VENUS GX) is mandatory for communication.
• Only specific Victron MultiPlus models, like the MultiPlus 48/3000/35, were compatible, and parallel/three-phase setups are not supported.
• Correct CAN-bus wiring and specific VEConfigure settings are critical for system operation.

How do I connect an LG Chem RESU battery to a Victron system?

Connecting an LG Chem RESU battery to a Victron system requires specific components and configuration steps. It is important to note that LG Chem RESU models are now End-of-Life and no longer supported by LG. The information provided here is for previously compatible systems, as documented by Victron Energy.

Why is my LG Chem RESU battery not communicating with my Victron GX device?

If your LG Chem RESU battery is not communicating or visible on your Victron GX device, several factors could be at play. The most common causes relate to incorrect cabling, missing components, or improper settings.

Diagnosis Steps

1. Verify GX Device Presence: Ensure a Victron GX device (Color Control GX or VENUS GX) is installed. Without it, the LG Resu will open its internal circuit breaker after 10 minutes.
2. Check GX Device Firmware: Confirm the GX device is running the minimum required firmware. For the Color Control GX, this is v2.15.
3. Inspect CAN-bus Cable: Use the correct VE.Can to CAN-bus BMS type B Cable (part number ASS030720018). Ensure the side labeled "Battery BMS" is plugged into the LG Chem Resu BMS and the side labeled "Victron VE.Can" is plugged into the GX device.
4. Confirm CAN-bus Terminator: A VE.Can terminator must be plugged into the other VE.Can socket on the GX device.
5. Check LG Resu SW Switches: For LG Resu models 3.3, 6.5, and 10, set SW select switches 3 & 4 on the battery to select the "LGC Smart" protocol.
6. Verify GX Device CAN-profile: Navigate to Settings -> Services -> CAN-profile on the GX device and ensure "CAN-bus BMS (500 kbits/s)" is selected.

Cause/fix table section

Victron and LG Chem RESU Battery Configuration

This section details the necessary components and settings for integrating previously compatible LG Chem RESU batteries with Victron Energy systems. It is crucial to follow these guidelines for proper operation.

Compatibility Overview

LG Chem RESU batteries were previously compatible with specific Victron MultiPlus inverter/charger models, such as the MultiPlus 48/3000/35. It is important to note that these batteries cannot be used in parallel or three-phase configurations with Victron systems. The documentation from Victron Energy regarding this compatibility is now End-of-Life and for archive purposes only, as LG no longer supports these RESU models.

Essential Components

1. Victron GX Device: A GX device, such as the Color Control GX (CCGX) or VENUS GX, is required. This device is essential for the CAN-bus connection, which provides the keep-alive signal, communicates charge and discharge limits, error codes, and the battery's state of charge (SOC). The minimum required firmware version for the Color Control GX is v2.15.
2. Victron ESS Installation: LG Chem RESU batteries can only be used in a Victron ESS (Energy Storage System) installation that utilizes the ESS Assistant. These systems are designed for on-grid self-consumption and are not suitable for off-grid applications.
3. MPPT Solar Chargers: If using MPPT solar chargers, they must have a VE.Direct port. VE.Can MPPTs are not supported with LG Chem RESU batteries.

Communication Setup

Proper communication between the LG Chem RESU battery and the Victron GX device is vital.

1. CAN-bus Cable: Use a specific VE.Can to CAN-bus BMS type B Cable, part number ASS030720018. Plug the side labeled "Battery BMS" into the LG Chem Resu BMS. Plug the side labeled "Victron VE.Can" into the GX device.
2. VE.Can Terminator: A VE.Can terminator must be plugged into the other open VE.Can socket on the GX device.
3. LG Resu SW Switches: For LG Resu models 3.3, 6.5, and 10, set the SW select switches 3 & 4 on the battery to select the "LGC Smart" protocol.
4. GX Device CAN-profile: On the GX device, navigate to Settings -> Services -> CAN-profile and select "CAN-bus BMS (500 kbits/s)".

VEConfigure Settings

The following settings must be configured in VEConfigure for the MultiPlus inverter/charger:

General Tab Settings

• Enable Battery Monitor: Check this option.
• Battery Capacity:
• • Resu 3.3: 63 Ah
  • Resu 6.4: 126 Ah
  • Resu 6.4 + 1 pcs EX 3.2: 189 Ah
  • Resu 6.4 + 2 pcs EX 3.2: 252 Ah
  • Resu 6.5: 126 Ah
  • Resu 10: 189 Ah

Charger Tab Settings

• Battery Type: Select "Lithium".
• Charge Curve: Set to "Fixed".
• Charge Parameters: | LG Resu Model | Absorption Voltage | Float Voltage | Absorption Time | |---|---|---|---| | 6.4 | 56.8 V | 56.7 V | 1 Hr | | 3.3, 6.5, 10 | 57.0 V | 57.0 V | 1 Hr |

ESS Assistant Settings

• Battery Type Selection: Select the fourth battery type option within the ESS Assistant.
• Sustain Voltage: Set to 50V.
• Dynamic Cut-off Value: Use a flat dynamic cutoff value of 46V. This setting allows the system to discharge to the CCGX set SOC limit of 15%, with a further self-discharge down to approximately 11% each night.

Firmware and Battery Behavior

It is recommended to use the latest firmware version for all connected Victron devices. However, do not attempt firmware updates using the LG Chem battery for power until you can confirm that the battery is connected and showing on the GX device. It is normal for LG Chem RESU batteries not to charge to 100%; the LG battery policy is to only charge the battery to 97% or 98%.

Safety: Lithium Battery Systems

Lithium-ion batteries, including LG Chem RESU models, require careful handling and installation due to their energy density. Always wear appropriate personal protective equipment, including eye protection, when working near batteries. Ensure all connections are secure and correctly polarized to prevent short circuits, which can lead to fire or explosion. The battery's internal Battery Management System (BMS) protects against overcharge, over-discharge, over-current, and extreme temperatures. Any attempt to bypass or interfere with the BMS can lead to dangerous conditions and void the warranty. Never open the battery enclosure.

When to call a technician instead

While basic setup and troubleshooting can be performed by a competent individual, certain situations warrant professional assistance. If you encounter persistent communication errors despite verifying all connections and settings, or if the battery displays unusual behavior (e.g., excessive heat, swelling, or unusual noises), contact a qualified solar technician. Any issues that could void the battery or inverter warranty, or that involve opening the battery unit, should also be handled by authorized service personnel.