--- title: "Wattsonic WTS 3-Phase Hybrid Inverter" description: "Wattsonic WTS 3-Phase hybrid inverter integrated via Modbus RTU. TapHome controls running modes, battery schedules, SOC protection and grid export." url: "https://taphome.com/en/compatibility/wattsonic-wts-3phase/" language: en lastmod: 2026-03-27 generator: hugo ai: topics: ["modbus-rtu","inverter","rs485","3-phase","hybrid-inverter","battery-storage"] questions: ["How to integrate Wattsonic WTS 3-Phase hybrid inverter with TapHome?","What does the Wattsonic WTS TapHome template monitor and control?","How to connect Wattsonic WTS inverter via RS-485 to TapHome?","How to change the running mode of Wattsonic WTS inverter via TapHome?","What battery monitoring is available for Wattsonic WTS in TapHome?","How to configure charge and discharge schedules for Wattsonic WTS via Modbus?"] --- # Wattsonic WTS 3-Phase Hybrid Inverter Communication: Modbus RTU - [Wattsonic Official Website](https://www.wattsonic.com) The Wattsonic WTS 3-Phase is a hybrid solar inverter series available in six models from 6 kW to 20 kW (WTS-4P-3P, WTS-5KW-3P, WTS-6KW-3P, WTS-8KW-3P, WTS-10KW-3P, WTS-12KW-3P). It supports dual MPPT PV inputs, lithium battery storage, on-grid and off-grid operation, and three-phase backup output. TapHome communicates with the inverter via Modbus RTU over RS-485 through the EMS port on the Multi-COM connector. The TapHome template provides comprehensive monitoring of PV generation, battery state, grid power flow, and per-phase measurements, along with control of running modes, charge/discharge time windows, SOC protection, grid export limits, and off-grid settings. ## Hardware connection ### Wiring overview ![Wattsonic WTS 3-Phase single inverter wiring diagram showing PV, battery, grid, backup, smart meter and communication connections](https://taphome.com/images/compatibility/wattsonic-wts-3phase/wiring-single-inverter_hu_ce43162614e87915.jpg) The inverter has all communication ports in the **Multi-COM connector** (COM2) at the bottom of the unit. There are two RJ45 ports (Meter and BMS) and a 20-pin terminal block for EMS, DRED, relay, emergency stop, and CAN parallel connections. ### RS-485 EMS connection ![Wattsonic Multi-COM connector showing Meter, BMS, and EMS ports with terminating resistor locations](https://taphome.com/images/compatibility/wattsonic-wts-3phase/multicom-connector-ports_hu_f6dfdcec8b3ba74e.jpg) Connect TapHome to the EMS RS-485 pins on the Multi-COM terminal block: | Multi-COM Pin | Definition | TapHome Connection | |---------------|------------|--------------------| | **13** | **485 B1** | B-/D- on TapHome RS-485 | | **14** | **485 A1** | A+/D+ on TapHome RS-485 | ![Wattsonic Multi-COM connector pin definition table — Pin 13 (485 B1) and Pin 14 (485 A1) for EMS communication](https://taphome.com/images/compatibility/wattsonic-wts-3phase/multicom-pin-definitions_hu_f131cf879d016ab0.jpg) > [!WARNING] > The Multi-COM connector uses a waterproof cable gland assembly. Wire diameter must be 4–6.5 mm, cross-sectional area 0.5–1.5 mm². Strip the outer insulation to 55 mm and inner wire insulation to 8 mm. Tighten terminal screws to 1.2 +/- 0.1 Nm. ### Terminating resistor A built-in RS-485 terminating resistor for the EMS bus is available on the communication port block (visible in the connector diagram above). Enable it only on the **last device** on the bus. TapHome Core has its own built-in 120 Ohm terminating resistor on BUS terminals. ## Configuration ### Communication parameters The Modbus RTU connection uses the following fixed parameters: | Parameter | Value | |-----------|-------| | Baud rate | 9600 | | Data bits | 8 | | Parity | None | | Stop bits | 1 | | Slave address | 1–247 (default 1) | | Byte order | Big-endian | ### Enabling Modbus communication The EMS RS-485 port is enabled by default on the Wattsonic WTS 3-Phase inverters. No additional configuration in the inverter menu or app is required to activate Modbus RTU communication. Simply connect the RS-485 wires to pins 13 and 14 on the Multi-COM connector and configure the correct Slave ID in TapHome. The default Slave ID is 1. If multiple inverters are on the same RS-485 bus, each must have a unique Slave ID. The Slave ID can be configured through the Wattsonic monitoring app or the inverter display panel. ## Device capabilities ### Running mode and system control The template provides full control over the inverter operating mode through the **Running Mode Setting** service action with four modes: - **General Mode** — PV power supplies loads first, then charges the battery, then exports to grid - **Economic Mode** — time-of-use optimization configured through charge/discharge time windows - **UPS Mode** — priority to battery backup for critical loads - **Off-Grid Mode** — standalone operation without grid connection The current **Running Mode** is displayed as a module-level service attribute. The **Inverter Running Status** service attribute shows the real-time state: Wait (waiting for grid), Check/Self-test, On Grid, Fault, Flash/Firmware update, or Off Grid. Additional system control switches: - **Off-Grid Running Switch** — enables or disables off-grid (backup) operation - **Asymmetric Output Switch** — enables asymmetric power output across phases for zero-injection mode - **Peak Load Shift Switch** — enables battery charging during off-peak hours and discharging during peak hours ### Battery management **Battery SOC** displays the state of charge as a percentage (0–100%) with eight service attributes providing detailed battery monitoring: - **Battery Health (SOH)** — state of health as percentage - **Battery Voltage** and **Battery Current** — real-time DC measurements - **Battery Power** — instantaneous charge/discharge power in kW - **Battery Charge/Discharge Energy Today** — daily energy counters in kWh - **Total Energy Charged/Discharged** — cumulative lifetime energy counters in kWh **Battery State** indicates the current charge/discharge direction (Charging or Discharging). Battery protection is configurable through: - **On-Grid SOC Protection** — enables SOC-based discharge cutoff while grid-connected - **Off-Grid SOC Protection** — enables SOC-based discharge cutoff in off-grid mode - **Off-Grid Battery DOD Setting** — configurable depth of discharge limit (0–100%) for off-grid mode ### Charge and discharge scheduling The module exposes **Charge Start Time**, **Charge Stop Time**, **Discharge Start Time**, and **Discharge Stop Time** as both readable service attributes and writable service actions. Each time value uses hour/minute encoding. The **Charge Start Time** service action accepts Hours (0–23) and Minutes (0–59) parameters. These time windows work with Economic Mode to optimize battery usage around electricity tariff schedules. ### Per-phase power monitoring Three electricity meter devices (**Phase A Power**, **Phase B Power**, **Phase C Power**) provide per-phase active power from the external meter in kW. Each phase includes nine service attributes: - **Backup Voltage**, **Backup Current**, **Backup Frequency**, **Backup Power** — measurements on the backup output port - **Inverter Power** — active power on the inverter grid port - **Grid Phase Voltage** and **Grid Phase Current** — grid-side measurements - **Grid Line-to-Line Voltages** — two line voltage readings per phase (e.g., A/B and C/A for Phase A) ### PV generation monitoring Two electricity meter devices monitor the dual MPPT inputs: - **PV1 & Total PV Generation** — PV string 1 instantaneous power (kW) and cumulative total PV generation from installation (kWh), with service attributes for PV1 current, PV1 voltage, total PV generation time, and total backup port energy - **PV2 & Total PV Generation** — identical structure for PV string 2 Additional PV sensors: - **PV Generation Energy Today** — daily PV energy production in kWh - **Total PV Generated Energy** — cumulative lifetime PV generation in kWh ### Grid monitoring and export control **Grid Frequency** displays the grid frequency in Hz with four service attributes for cumulative grid energy totals: - **Total Energy Purchased from Grid (Inverter Side)** and **(Meter Side)** — two measurement points for grid import energy - **Total Energy Injected to Grid** — cumulative grid export energy - **Total Loading Consumed Energy** — cumulative load consumption measured at grid side Daily energy counters: - **Grid Injection Energy Today** — daily grid export energy in kWh - **Grid Purchasing Energy Today** — daily grid import energy in kWh - **Loading Energy Today** — daily load consumption in kWh - **Backup Output Energy Today** — daily backup port energy in kWh **Grid Export Power Limit Switch** and **Grid Export Power Limit** (0–100%) enable limiting the power exported to the grid, useful for zero-injection or export limitation requirements. ### Temperature monitoring Four temperature sensors (**Temperature Sensor 1** through **4**) read internal inverter temperatures in degrees Celsius. ### Total AC power **Total Inverter AC Power** provides the sum of AC power across all three phases from the inverter in kW. ### System diagnostics The module ReadScript monitors two fault flag registers (H:10112, H:10113) and reports individual fault conditions including: Mains Lost, Grid Voltage/Frequency Fault, DCI Fault, ISO Over Limitation, GFCI Fault, PV Over Voltage, Bus Voltage Fault, Inverter Over Temperature, SPI/E2 Fault, AC Transducer Fault, Relay Check Fail, and Internal/External Fan Fault. The **Clear Over-load Protection Flag** service action resets the overload protection lockout after an overload event has been resolved. The **Model Info** service attribute identifies which of the six WTS models is connected, and **Date and Time** reads the inverter's internal RTC clock. ### Additional capabilities The Wattsonic WTS 3-Phase inverters also expose registers for total 3-phase meter power, total 3-phase backup power, combined PV input power, BMS diagnostics (pack temperature, cell-level min/max voltage and temperature, charge/discharge current limits, status and error codes), off-grid output voltage and frequency settings, per-phase and total inverter power settings, on-grid battery DOD threshold, charge/discharge power limits, and firmware/hardware version information. These can be added in a future template update. ## Troubleshooting ### No Modbus communication 1. Verify wiring: Pin 13 (485 B1) to B-/D- and Pin 14 (485 A1) to A+/D+ on TapHome. Swapped A/B wires are the most common connection issue. 2. Confirm communication parameters in TapHome: 9600 baud, 8 data bits, no parity, 1 stop bit. 3. Check the Slave ID matches between the inverter and TapHome configuration (default is 1). 4. If using a long RS-485 cable, enable the terminating resistor on the last device. 5. Check the Communication LED on the inverter front panel — green flashing indicates active RS485/CAN communication. ### Inverter shows "Wait" status The inverter enters Wait status when the grid is not detected or grid parameters are outside the configured regulation limits. This is normal during grid outages. The **Inverter Running Status** service attribute will show "Wait, wait for on grid" (value 0). ### Cloud app and Modbus control conflicts Changes made through the Wattsonic cloud app and Modbus local writes may not synchronize bidirectionally. When using TapHome for inverter control, avoid making conflicting changes through the cloud app simultaneously. ## Available devices Wattsonic WTS 3-Phase Module Service Attributes | | | |-------------------------|----------------------------------------------------------------------------------------------------| | Model Info | | | Date and Time | | | Inverter Running Status | Current inverter operating state — Wait, Check/Self-test, On Grid, Fault, Flash/Firmware, Off Grid | | Charge Start Time | | | Charge Stop Time | | | Discharge Start Time | | | Discharge Stop Time | | | Running Mode | Current inverter operating mode — General, Economic, UPS, or Off-Grid | Service Actions | | |---------------------------------| | Charge Start Time | | Running Mode Setting | | Clear Over-load Protection Flag | Asymmetric Output Switch Switch Enables asymmetric power output across phases for zero-injection mode Register: H:50006 UInt16 Values / States: ON · OFF Backup Output Energy Today Variable Read-only Register: H:41002 UInt16 Unit: kWh numeric Battery SOC Dimmer Read-only Battery state of charge as percentage with detailed monitoring — health, voltage, current, power, and daily/lifetime energy counters Register: H:43000 UInt16 Unit: % numeric Service Attributes | | |--------------------------------------| | Battery Health | | Battery Voltage | | Battery Current | | Battery Power | | Battery Charge Energy Today | | Battery Discharge Energy Today | | Total Energy Charged to Battery | | Total Energy Discharged from Battery | Battery State Reed Contact Read-only Battery charge/discharge direction — Charging or Discharging Register: H:40256 UInt16 Grid Frequency Variable Read-only Grid frequency in Hz with cumulative energy counters for grid import, export, and load consumption Register: H:11015 UInt16 Unit: Hz numeric Service Attributes | | |---------------------------------------------------| | Total Energy Purchased from Grid at Inverter Side | | Total Energy Injected to Grid | | Total Loading Consumed Energy on Grid Side | | Total Energy Purchased from Grid from Meter | Grid Injection Energy Today Variable Read-only Register: H:41000 UInt16 Unit: kWh numeric Grid Export Power Limit Dimmer Configurable grid export power limit as percentage (0–100%) Register: H:25103 UInt16 Unit: % numeric Grid Export Limit Switch Switch Register: H:25100 UInt16 Values / States: ON · OFF Grid Purchasing Energy Today Variable Read-only Register: H:41001 UInt16 Unit: kWh numeric Loading Energy Today Variable Read-only Register: H:41006 UInt16 Unit: kWh numeric Off-Grid Battery DOD Dimmer Depth of discharge limit for off-grid mode — battery stops discharging when SOC drops below this threshold Register: H:52505 Int16 Unit: % numeric Off-Grid Running Switch Switch Register: H:50001 UInt16 Values / States: ON · OFF Off-Grid SOC Protection Switch Enables SOC-based discharge cutoff in off-grid mode to prevent deep battery discharge Register: H:52504 UInt16 Values / States: ON · OFF On-Grid SOC Protection Switch Enables SOC-based discharge cutoff while grid-connected to prevent deep battery discharge Register: H:52502 UInt16 Values / States: ON · OFF Peak Load Shift Switch Switch Enables battery charging during off-peak hours and discharging during peak hours Register: H:50007 UInt16 Values / States: ON · OFF Phase A Power Electricity Meter Read-only Phase A active power from external meter (kW) with backup, inverter, and grid voltage/current measurements Register: H:10994 Int32 Unit: kW numeric Service Attributes | | |------------------------| | Backup Voltage | | Backup Current | | Backup Frequency | | Backup A Power | | Inverter A Power | | Grid Phase A Current | | Grid Phase A Voltage | | Grid Lines A/B Voltage | | Grid Lines C/A Voltage | Phase B Power Electricity Meter Read-only Phase B active power from external meter (kW) with backup, inverter, and grid voltage/current measurements Register: H:10996 Int32 Unit: kW numeric Service Attributes | | |------------------------| | Backup Voltage | | Backup Current | | Backup Frequency | | Backup Power | | Inverter Power | | Grid Phase B Current | | Grid Phase B Voltage | | Grid Lines A/B Voltage | | Grid Lines B/C Voltage | Phase C Power Electricity Meter Read-only Phase C active power from external meter (kW) with backup, inverter, and grid voltage/current measurements Register: H:10998 Int32 Unit: kW numeric Service Attributes | | |------------------------| | Backup Voltage | | Backup Current | | Backup Frequency | | Backup C Power | | Inverter C Power | | Grid Phase C Current | | Grid Phase C Voltage | | Grid Lines C/A Voltage | | Grid Lines B/C Voltage | PV Generation Energy Today Variable Read-only Register: H:41005 UInt16 Unit: kWh numeric PV1 & Total PV Generation Electricity Meter Read-only PV string 1 instantaneous power (kW) and cumulative total PV generation (kWh) with PV1 voltage/current details Register: H:11062 (demand), H:11020 (total) UInt32 Unit: kW / kWh numeric Service Attributes | | |------------------------------------| | PV1 Current | | PV1 Voltage | | Total PV Generation Time | | Total Output Energy on Backup Port | PV2 & Total PV Generation Electricity Meter Read-only PV string 2 instantaneous power (kW) and cumulative total PV generation (kWh) with PV2 voltage/current details Register: H:11064 (demand), H:11020 (total) UInt32 Unit: kW / kWh numeric Service Attributes | | |------------------------------------| | PV2 Current | | PV2 Voltage | | Total PV Generation Time | | Total Output Energy on Backup Port | Temperature Sensor 1 Temperature Sensor Read-only Register: H:11032 Int16 Unit: °C numeric Temperature Sensor 2 Temperature Sensor Read-only Register: H:11033 Int16 Unit: °C numeric Temperature Sensor 3 Temperature Sensor Read-only Register: H:11034 Int16 Unit: °C numeric Temperature Sensor 4 Temperature Sensor Read-only Register: H:11035 Int16 Unit: °C numeric Total Inverter AC Power Variable Read-only Sum of AC power across all three phases from the inverter (kW) Register: H:11016 Int32 Unit: kW numeric Total PV Generated Energy Variable Read-only Register: H:41112 UInt32 Unit: kWh numeric **Connection:** Modbus RTU • 9600 baud• 8N1 • Slave ID: $\[SlaveId] Possible improvements (32) - H:10000 Inverter Serial Number — STR (8 registers) — device identification - H:10011 Firmware Version — U32 — firmware identification - H:10104 Grid Regulation — U16 — grid regulation code - H:10114 Fault FLAG2 — U32 — second set of fault codes (partially read by readscript as DeviceError1 at H:10113, but protocol specifies H:10114 as U32) - H:10120 Fault FLAG3 — U32 — third set of fault codes, not read by readscript at all - H:11000 Total Power on Meter — I32 /1000 kW — total 3-phase meter power. Per-phase power IS implemented but total is not - H:11002 Total Grid-Injection Power on Meter — U32 /100 kWh — cumulative total grid injection (meter) - H:11004 Total Purchasing Power from Grid on Meter — U32 /100 kWh — cumulative total grid purchasing (meter) - H:11018 Total PV Generation on that day — U32 /10 kWh — same as daily PV generation but as U32 (template uses H:41005 UInt16 instead) - H:11028 PV Input Total Power — U32 /1000 kW — combined PV1+PV2 input power - H:18000 ARM Fault FLAG1 — U32 — ARM processor faults (SCI, FLASH, Meter Comm) - H:40230 Total Backup Power — I32 /1000 kW — total 3-phase backup power - H:41008 Energy Purchased from Grid Today — U16 /10 kWh — daily energy purchased from grid (inverter side) - H:42003 BMS Software Version — U16 — BMS firmware identification - H:42004 BMS Hardware Version — U16 — BMS hardware identification - H:42005 BMS Charge Imax — U16 /10 A — maximum charge current allowed by BMS - H:42006 BMS Discharge Imax — U16 /10 A — maximum discharge current allowed by BMS - H:43002 BMS Status — U16 — BMS operating status - H:43003 BMS Pack Temperature — U16 /10 °C — battery pack temperature - H:43008–43015 BMS Cell Temperature/Voltage Min/Max — 8 registers — cell-level min/max temperature and voltage with cell IDs - H:43016 BMS Error Code — U32 — BMS error code bitmap - H:43018 BMS Warning Code — U32 — BMS warning code bitmap - H:50004 Off-Grid Output Voltage — U16 /10 V — configurable off-grid output voltage - H:50005 Off-Grid Output Frequency — U16 /100 Hz — configurable off-grid output frequency (45.00–65.00 Hz) - H:50009 Maximum Grid Power Limit — U16 /10 kVA — maximum grid power limit - H:50010 Inverter Power Setting Mode — U16 — 0=Off, 1=Total Power (50011), 2=Per Phase (50012–50014) - H:50011 Total Power Setting — I16 /100 kW — total power setting (when mode=1) - H:50012–50014 Phase A/B/C Power Setting — I16 /100 kW each — per-phase power settings (when mode=2) - H:50200 Enable Off-Grid Running Function — U16 WO — 0=Disable, 1=Enable. Write-only trigger - H:52503 On-Grid Battery DOD Setting — U16 /1000 (0.0–100.0%) — on-grid depth of discharge limit. On-grid SOC Protection switch IS implemented but the DOD value is not - H:53002 Charge Power Limit — U16 /1000 (0.0–100.0%) — charge power limit as percentage - H:53005 Discharge Power Limit — U16 /1000 (0.0–100.0%) — discharge power limit as percentage ## Sources - Wattsonic Hybrid Inverter Protocol — Three Phase V1.0 2026-03-27 [PDF](https://taphome.com/compatibility/devices/wattsonic-wts-3phase/manufacturer/wattsonic-wts-3phase-protocol.pdf) - Wattsonic Li-HV Residential Three Phase Hybrid Series — User Manual (Sep 2024) [oss.wattsonic.com](https://oss.wattsonic.com/wattsonic/docs/Wattsonic%20Li-HV%20Residential%20Three%20Phase%20Hybrid%20Series_UM_EN.pdf) 2026-03-27 [PDF](https://taphome.com/compatibility/devices/wattsonic-wts-3phase/manufacturer/wattsonic-user-manual.pdf) ## Related Documentation - [Modbus Integration](https://taphome.com/en/compatibility/modbus-guide/) - [Modbus](https://taphome.com/en/docs/integration/modbus/) - [Simple configuration using templates](https://taphome.com/en/docs/integration/modbus/templates/) - [Modbus scripts and prefetch](https://taphome.com/en/docs/script/modbus-scripts/) - [Modbus functions](https://taphome.com/en/docs/script/modbus/) - [Modbus data types](https://taphome.com/en/docs/script/modbus-data-types/)