Mikrosilver video provides additional information and a detailed setup guide:

The ADA485 is an easy-to-install RS485→IP (Wi-Fi/LAN) bridge and edge gateway. It reads and writes Modbus RTU, publishes to MQTT/HTTP/REST, logs to CSV/JSON, and is immediately usable with Home Assistant/smartmeter.okosvillanyora.hu/hmke.app systems. Ideal for inverters (Deye/Sunsynk, Fronius RS485), BMS (SEPLOS, Basen), PZEM meters, heat pumps, boilers, PLCs. New feature: it also emulates a DTSU666 electricity meter in Modbus RTU slave mode — so when connected directly to the Deye inverter's 2Meter port, it regulates feed-in power without a physical meter based on P1 smart meter data.

WARNING! Power supply and USB cable not included!
The ADA485 is the GreenHESS ADA ecosystem’s RS485/Modbus TCP/Modbus gateway device. Its task is to connect meters/controllers available on the standard Modbus RTU line locally, even without the cloud, to the home or industrial IP network.

Main uses:

• HMKE solar energy systems: real-time monitoring and control of inverter, smart meter, BMS.

• Heating-cooling: heat pump, boiler, buffer tank, heat quantity meter over RS485.

• Industrial/building automation: PLC, frequency converter, temperature/pressure transmitter, PZEM, etc.

• Smart Meter replacement: DTSU666 emulator for Deye/Sunsynk inverter 2Meter port — without a physical electricity meter.

Features in detail

Communication channels

• Modbus RTU master: read/write, multiple slaves on one bus, scheduled queries, on-demand command sending.

• Modbus RTU slave (new!): acts as a data provider itself — with Eastron SDM630 (FC04) or CHNT DTSU666 (FC03) emulation.

• Modbus TCP client (on LAN): fast polling without RS485, supports persistent connection.

• Solarman protocol: native Solarman V5 frame support for Deye/Sunsynk inverters (serial number based).

• HTTP/REST pull + JSON-path: extract and unify arbitrary API fields.

• RS485 ASCII frames: ascii/hex/hextoascii template + optional frame suffix.

• MQTT publish/subscribe: real-time data and remote control (set-mode, get-status, get-config, raw send) to EMQX broker.

Edge processing and calculations

• Scaling and signed number handling: divider, mask, signed/unsigned, two's complement, byte order (BE/LE).

• Computed fields: expression-based derived values (e.g. batt_i_charge, batt_i_dis, phase sums, P/U/I conversions).

• Multiple requests → one payload: e.g. inverter + BMS data into a single JSON object.

• Field-level send-enable (adasend): select keys for MQTT publishing.

• Cache and state management: preserves last valid data, gate conditions to filter incomplete data.

Web administration

• Captive portal Wi-Fi setup: on first start switches to AP mode, configurable from phone.

• Built-in protocol editor: CodeMirror-based JSON editor for live profile editing.

• Encrypted protocol files: shipped profiles obfuscated with VB-style and decryptable with key.

• Live data interface: displays phase voltages, currents, powers, energies, frequency.

• Modbus traffic decoder: last request/response hex dump and register-level interpretation (name + unit + decoded float value).

• Event log: MQTT send/receive timeline, acknowledged commands, errors.

Operation

• OTA updates: via browser or automatic pull from firmware.greenhess.com.

• Logging: local CSV and JSON logs (LittleFS), periodic push to server.

• Fault tolerance: watchdog reset, automatic reconnection after Wi-Fi/MQTT loss, persistent configuration in flash.

• Multitask architecture: ESP32 dual-core utilization — network operations (HTTP, MQTT) and Modbus slave responses run on separate CPU cores with priority-based FreeRTOS scheduling. Ensures time-sensitive polling devices (e.g. Deye inverter 100 ms 2Meter polling) get timely response.

Smart Meter emulation (DTSU666 / Eastron mode)

One of the most special features of ADA485 firmware is the Modbus RTU slave mode: the device itself becomes the electricity meter for the inverter, without a physical DTSU666 or Eastron SDM630 meter. It reads data over Wi-Fi from the P1 smart meter (okosvillanyora.local) JSON API, then serves the inverter in the expected Modbus RTU format over the RS485 bus.

Typical use: where a smart meter already exists (with P1 dongle), no separate DTSU666 meter purchase is needed for the Deye 2Meter port. ADA485 implements both data collection and meter emulation in a single device.

Selectable protocols

EASTRON SDM630 mode (FC04 — Read Input Registers)

• SI base units: V, A, W, Hz, kWh — directly as IEEE754 float.

• Complete register map in range 0x0000-0x0164: phase voltages, currents, active/reactive/apparent power per phase and total, PF, frequency, import/export energy, line-line voltages.

• No scaling issues — native SDM630 compatibility.

CHNT DTSU666 mode (FC03 — Read Holding Registers)

• Official CHINT DTSU666 ModBus protocol v1.5 register map.

• Instantaneous measurement block: 0x2000-0x2030 (Uab/Ubc/Uca, Ua/Ub/Uc, Ia/Ib/Ic, Pt/Pa/Pb/Pc, Qt/Qa/Qb/Qc, St/Sa/Sb/Sc, PFt/PFa/PFb/PFc).

• Frequency: 0x2044.

• Energy block (official address): 0x4000 (ImpEp), 0x400A (ExpEp), 0x4014 (ImpEq), 0x401E (ExpEq).

• Backward compatibility: addresses 0x101E/0x1028 of Huawei DTSU666-H also supported.

Scaling profiles

Different Deye firmware versions may expect different scalings on the same registers. To handle this, three preset profiles are available in CHNT mode, offering solutions for most cases without parameterization:

• DTSU666 classic (default): factory CHINT scaling — V×10, I×1000, P×10, Q×10, PF×1000, Hz×100, energy in native kWh. Works with most 2024+ Deye firmware.

• Native SI: all values directly in SI base units — V, A, W, Hz, kWh. Expected by some newer firmware builds.

• Custom: multipliers for 7 field groups (V, I, P, Q, PF, Hz, E) can be individually set, if neither DTSU666 classic nor Native fits.

Live diagnostic tools

• Modbus traffic decoder: web interface shows last inverter request (address, FC, register range) and ADA485’s response — with register names, units, "wire" values and calculated SI values. Enables rapid detection of scaling errors.

• Test mode: P1 polling can be temporarily disabled and fixed values injected towards the inverter (e.g. P_L1=-500W, P_L2=+1000W, P_L3=-1500W). This verifies exact values shown on inverter display, essential for calibration and installation validation.

• Statistics: counters query_count, query_ok, query_fail, P1 fetch success, last request timestamp.

• Frequency sanity check: if P1 source gives 0 Hz (some smart meters behave this way), firmware automatically sends 50 Hz to prevent meter error on inverter.

Remote configuration

All parameters of meter slave mode (protocol, P1 host/port/path, slave address, fetch period, scaling profile, custom multipliers, test values) can also be set via MQTT, not only through the web interface. This allows configuring multiple ADA485 units remotely or automatic switching for different inverter types from a supervisory system.

Quick installation (5 steps)

1. Wiring: RS485 A/B/GND → meter/inverter bus (A to A, B to B; polarity matters). 120 Ω termination recommended at bus ends.

2. Power: connect ADA485 power supply (according to range on label – typically 5…24 V DC).

3. Wi-Fi: connect to ADA485 AP from phone/computer → web setup (SSID, password).

4. MQTT/REST: enter broker address or local API endpoint.

5. Profile: select/load ready Modbus profile (e.g. Deye SUN-xK-SG04LP3-EU), save, START. For meter slave mode: select CHNT DTSU666 or Eastron protocol, enter P1 meter address, choose scaling profile.

Wiring

RS485 basic rules

• Two-wire, shielded twisted pair recommended (e.g. LiYY/UTP): A(+) ↔ A(+), B(−) ↔ B(−).

• A common GND reference often improves noise immunity (if device allows).

• 120 Ω termination at both ends of bus; bias (pull-up/down) usually at one point, near the master.

Example pinout (terminal block):

• RS485-A (signal +)

• RS485-B (signal −)

• GND (optional reference)

For RJ45 port always follow device labeling; there is no universal RJ45 standard for RS485.