Victron Discover AES LYNK Gateway Setup and Troubleshooting

Key Takeaways

• Correct CAN-bus communication speed is crucial; typically 250 kbit/s for Victron, but 500 kbit/s for HELIOS ESS.
• The LYNK II Gateway requires specific PC software for configuration.
• Use a standard patch cable (CAT5e or higher) for Discover AES to Victron GX communication, not a cross-over cable.
• If closed-loop communication fails, you may need to switch to open-loop mode and consult a professional.

Why is my Discover AES battery not communicating with my Victron GX device?

Most commonly, communication issues stem from incorrect CAN-bus settings or improper cabling. The first step is to verify the communication speed and cable type between your Discover AES battery system and the Victron GX device.

Diagnosis

Follow these steps to diagnose common communication problems between your Discover AES battery system and Victron GX device.

1. Check Victron GX Device List for Discover AES:

• • Observable: The Discover AES battery does not appear on the "Device List" within your Victron GX device interface.
  • Meaning: This often indicates a physical cabling issue preventing initial detection.
  • Action: Confirm that the communication cable connecting the Discover AES battery (or LYNK II Gateway) to the Victron GX device is a normal patch type (CAT5e or higher), not a cross-over type.

2. Verify CAN-bus Communication Speed on Victron GX:

• • Observable: Communication errors persist, or no battery data is displayed, even with the correct cable.
  • Meaning: The Victron GX device's CAN-bus speed may not match the required speed for the Discover AES system.
  • Action: On your Victron GX device, navigate to Settings > Services > VE.Can port > CAN-bus profile. Select VE.Can & CAN-bus BMS (250 kbit/s). If you are using a HELIOS ESS battery, the communication rate should be set to 500 kbit/s to match the HELIOS ESS battery.

3. Confirm LYNK II Gateway Configuration:

• • Observable: The LYNK II Gateway is connected, but closed-loop CAN communication with the Victron GX device is not established.
  • Meaning: The LYNK II Gateway requires specific software configuration to enable full communication.
  • Action: Ensure that the LYNK ACCESS software (for 64-bit Windows 10 / 11) has been used to configure the LYNK II settings for closed-loop CAN communication with Victron Energy devices.

4. Inspect HELIOS ESS COM2 Port Connection and Speed:

• • Observable: Specific communication issues with a HELIOS ESS battery connected to a Victron GX device.
  • Meaning: Incorrect cable type or speed setting for the HELIOS ESS.
  • Action: Connect a modified CAT6 or higher cable from the HELIOS ESS COM2 port to the CAN port of the Victron GX device. Then, set the VE.Can port and CAN-Bus BMS communication rate on the GX device to 500 kbit/s.

5. Check LYNK II Network Termination:

• • Observable: Unstable or intermittent communication, or communication failures after modifying the gateway.
  • Meaning: Incorrect CAN-bus termination can disrupt signal integrity.
  • Action: The LYNK II Communication Gateway terminates the LYNK Network by default. Do not remove the termination jumper inside the LYNK II Communication Gateway unless you have been specifically instructed to do so.

Cause/fix table

Communication Faults: Protocols, Cables, and Settings

Establishing reliable communication between your Discover AES battery system and a Victron GX device involves understanding CAN-bus protocols, verifying cabling, and correctly configuring device settings.

CAN-bus Protocol Basics: The LYNK II Gateway facilitates CAN-bus communication, a standard for robust data exchange in industrial and automotive applications. For Discover AES batteries, this enables the Victron GX device to monitor battery status, state of charge (SOC), and other critical parameters. The Victron protocol typically operates at 250 kbit/s. However, some Victron devices or specific battery models like the HELIOS ESS may require a communication speed of 500 kbit/s.

Cable and Pinout Checks: The physical connection is critical. For Discover AES to Victron GX communication, use a standard patch cable (CAT5e or higher). A cross-over cable will prevent communication. For custom connections or specific applications, the LYNK II Gateway allows for adjustment of CAN signal pin assignments on its RJ45 connector. The standard assignments are CAN L on pin 8, CAN H on pin 7, and CAN GND on pin 3. These adjustments are made via jumpers on the header board inside the gateway.

Protocol-Select Settings: The Victron GX device requires specific configuration to recognize and communicate with the Discover AES system. This involves selecting the correct CAN-bus profile. Navigate to Settings > Services > VE.Can port > CAN-bus profile and select VE.Can & CAN-bus BMS (250 kbit/s). For HELIOS ESS batteries, ensure the communication rate is set to 500 kbit/s on the Victron GX device to match the battery's speed.

Firmware Note: While not explicitly covered in the provided information, ensuring both your Victron GX device and LYNK II Gateway have the latest compatible firmware can often resolve communication glitches. Always consult the manufacturer's documentation for firmware update procedures.

Safety: Electrical Connections

Always prioritize safety when working with battery systems and electrical connections.

• Isolate Power: Before making or changing any electrical connections, ensure all power sources (PV, battery, AC) are isolated. Turn off all breakers and disconnect battery terminals.
• Insulated Tools: Use insulated tools to prevent accidental short circuits. A spanner across battery terminals can short hundreds of amps, causing severe damage or injury.
• Cable Integrity: Ensure all communication cables are undamaged and properly secured. Loose connections can lead to intermittent faults or system instability.

When to call a technician instead

While many communication issues can be resolved with careful troubleshooting, there are situations where professional assistance is necessary. If you have followed all diagnostic steps and communication cannot be restored, or if you are uncomfortable performing any of the recommended actions, contact a qualified solar technician. If communication cannot be restored, you may have to set the system to open loop until an installation professional is available. Modifying internal components of the LYNK II Gateway beyond adjusting specified jumpers should only be done by authorized service personnel to avoid voiding warranties or damaging the device.