Modbus Reference · Deye
Deye Modbus TCP registers
Register reference for reading Deye (and rebrands like Sunsynk) inverters over Modbus TCP, including high-voltage and low-voltage battery registers and the grid meter.
Connection parameters: Modbus TCP on port 502, function code FC03 (Read Holding Registers). The default unit ID is 1.
Production registers
| Function | Register(s) | Raw format | Scaling | Metric | App output |
|---|---|---|---|---|---|
| FC03 | 80–81 | U32 BE | × 0.1 W | Instantaneous inverter power | Whole Watts |
| FC03 | 63–64 | U32 BE | × 0.1 kWh | Lifetime energy production | Wh (raw × 100) |
| FC03 | 150 | S16 | × 0.1 V | Grid voltage, L1 | Volts |
Battery registers (high-voltage three-phase)
| Register(s) | Raw format | Scaling | Metric | Sign handling |
|---|---|---|---|---|
| 587 | S16 | × 0.1 V | Battery voltage | – |
| 593 | U16 | × 1% | State of charge | Clamped to 0–100% |
| 594 | S16 | × 1 W | Battery power | Positive discharge value is negated |
Efficient read: 587–594 as one block.
Battery registers (low-voltage single-phase)
| Register(s) | Raw format | Scaling | Metric | Sign handling |
|---|---|---|---|---|
| 183 | S16 | × 0.01 V | Battery voltage | – |
| 189 | U16 | × 1% | State of charge | Clamped to 0–100% |
| 190 | S16 | × 1 W | Battery power | Positive discharge value is negated |
Efficient read: 183–190 as one block. Note the 0.01 V voltage scaling on low-voltage models versus 0.1 V on high-voltage models.
Grid meter registers
| Register(s) | Raw format | Scaling | Metric | Sign convention |
|---|---|---|---|---|
| 178 | S16 | × 1 W | Instantaneous grid power | Deye positive = import; value is negated for positive-export convention |
| 76–77 | U32 BE | × 0.1 kWh | Cumulative exported energy | Wh (raw × 100) |
| 78–79 | U32 BE | × 0.1 kWh | Cumulative imported energy | Wh (raw × 100) |
Sign conventions used throughout: grid power is normalized so positive = exporting and negative = importing. Battery power is normalized so charging and discharging follow the app's convention noted per table.
Deye systems usually reach the LAN through a Solarman logger stick; whether it speaks raw Modbus TCP depends on the stick's firmware. RS485-to-TCP gateways wired to the inverter are the dependable fallback.
Want this data on your phone, without a server?
These are the registers SolarMark reads. The app polls your inverter directly over your local network: live power, energy history, battery State of Charge, and grid import/export, with no cloud account and no Home Assistant server to maintain. One-time purchase with a free 14-day trial. Get it on Google Play or the App Store.