Inverter: SAJ

Caution

Working with high voltage is dangerous. Always follow local laws and regulations regarding high voltage work. If you are unsure about the rules in your country, consult a licensed electrician for more information.

SAJ inverter wiki page

Types of compatible SAJ inverters

H2 Hybrid

• 3~6K-S2 Ver.
• 5~10K-S3 Ver.
• 5~10K-T2 Ver.
• 15~20K-T2 Ver.

SAJ H2-10K-T2 was the first SAJ inverter to be successfully used with Battery-Emulator

SAJ H2-8K-T2 hybrid inverter also used with Battery Emulator

• Module Firmware : V1.214 (upgraded by SAJ to allow Modbus)
• Display Board : V2.231 (upgraded by SAJ to allow AI mode)
• Control Board : V4.139

Inverter protocol

The SAJ inverter uses the Pylon CAN protocol (Pylon-SC0500)

Settings on the Battery Emulator side

#define PYLON_CAN

For >255Ah batteries, the latest version contains a bugfix for the 732x frames to the inverter

Specific settings are not needed regarding geometry of the battery

For a 72-cell battery 280Ah LFP battery, this works for me

• TOTAL_CELL_AMOUNT = 72;
• MODULES_IN_SERIES = 4;
• CELLS_PER_MODULE = 18;
• VOLTAGE_LEVEL = 230;
• AH_CAPACITY = 280;

This is the can_config part for the inverter

• .inverter = CAN_ADDON_MCP2515,

The battery shows up in the Elekeeper APP with the following parameters as reported by the Battery Emulator

• Design Capacity
• Actual Ah Remaining Capacity
• Actual % Remaining Capacity
• (Dis)charge Power
• Temperature
• Number of Modules

When going deeper into the Elekeeper APP (change battery settings) via BT or cloud

• Zero voltage displayed for the 4 modules
• Modules appear as 16 cell instead of declared 18 cell
• The inverter only looks at low and high SOC% disconnect values implement on inverter side, no effect by changing the battery threshold settings on webinterface of BE

WIP on the mapping of the battery modules towards the Pylon modules.