Enabling LYNK II to Communicate with SUNSYNK Devices

When properly connected to a managed (closed-loop) network and set to use the SUNSYNK protocol, LYNK II will transmit real-time parameters from the Discover Lithium battery, including voltage, current, temperature, state of charge, and fault conditions to a SUNSYNK inverter-charger. LYNK II will also transmit charge voltage and current requests from the Discover Lithium battery to a SUNSYNK inverter-charger.

LYNK ACCESS software for 64-bit Windows 10 / 11 is required to configure LYNK II settings for managed (closed-loop) CAN communication with SUNSYNK inverter-chargers.

If there is a break in communication between the LYNK II and inverter-charger for more than ten seconds, the inverter-charger will safely stop operation, so long as the BMS Lithium Batt and the BMS_Err_Stop parameters are both enabled on the SUNSYNK inverter-charger. The inverter-charger will display an F58 BMS Communication Fault if communication is lost. The SUNSYNK inverter-charger will check every five minutes and resume managed (closed-loop) operation if communication is re-established. However, if communication cannot be reestablished, you may have to manually convert the SUNSYNK inverter-charger to a self-managed (open-loop) configuration to resume operation. Refer to SUNSYNK Self-Managed (Open-Loop) Configuration.

NOTE

In a managed (closed-loop) configuration with the BMS Lithium Batt function enabled, the BMS_Err_Stop parameter must be enabled. If the BMS_Err_Stop parameter function is not enabled, the SUNSYNK inverter-charger will continue to operate based on the last communicated battery values. Depending on the mode of operation at the time of a communication fault, and given enough time, the SUNSYNK inverter-charger will eventually put the attached battery into an overcharged or fully discharged state. When that occurs, either situation will trigger the Discover Lithium Battery BMS to self-protect and disconnect the battery from the system.
Neither Discover Lithium batteries nor LYNK II directly control SUNSYNK relay functions, generator starting, or other grid-interactive features. These functions are controlled through the programming of the SUNSYNK inverter-charger.