HomeMaster

Modular smart home automation with local logic

HomeMaster is the in-house brand of ISYSTEMS AUTOMATION: DIN-rail modules and controllers for lighting, heating, energy metering, leak detection and boiler control — with logic on every module, RS-485 Modbus between devices, and integration through ESPHome and Home Assistant. No cloud dependency; the system keeps working when the network does not.

The product range, shop, system configurator and documentation live at home-master.eu.

Deterministic communication

RS-485 Modbus RTU between modules — stable on long cable runs and in electrically noisy panels.

Modular and scalable

DIN-rail I/O, metering, dimming, leak detection and alarm modules expand around a MiniPLC or MicroPLC controller as the installation grows.

Local logic on every module

Wall-switch scenes, shutter interlocks, valve shut-off, load balancing and boiler interfaces can run on the module itself. Critical functions continue if the controller or Wi-Fi link is down.

Fully local operation

Automation runs on the devices in the panel. Internet is optional — for remote access and updates, not for day-to-day control.

Controllers

MiniPLC

DIN-rail controller with relays, I/O, temperature inputs, display and integrated supply. RS-485 Modbus expansion for a full cabinet from one unit.

MicroPLC

Compact ESP32 controller for smaller panels: one relay, digital input, RS-485 and Wi-Fi. Controls the Modbus module bus without the cost of a full PLC when the I/O lives on the modules.

DIN-rail modules

DIO-430-R1 — relay and digital input module; wall switches, scenes and shutter interlock handled locally.
AIO-422-R1 — 0–10 V in and out, PT100/PT1000 RTD on one module.
ENM-223-R1 — three-phase energy metering, power quality events and load balancing.
WLD-521-R1 — five leak zones, valve shut-off and water metering.
OTGW-R1 — OpenTherm boiler interface; ESPHome-native.
DIM-420-R1 — AC dimmer for lighting circuits.
RGB-621-R1 — RGBCCT LED control.
STR-3221-R1 — stair and corridor LED sequencing.
ALM-173-R1 — alarm and security inputs.

HomeMaster DIO-430-R1 relay and digital input module

HomeMaster OTGW-R1 OpenTherm Gateway module

In the panel

HomeMaster DIN-rail modules and MiniPLC controller mounted on a galvanized backplate

Modules share a 35 mm DIN rail, terminal blocks and RS-485 bus — the same layout whether the panel serves one apartment or a small building.

Wired HomeMaster control panel with MiniPLC, I/O modules and circuit protection

Designed and built in-house

HomeMaster MiniPLC printed circuit board with ESP32, display header and field terminals

Every HomeMaster product is designed, assembled and tested at our premises in Ploiești. Firmware, schematics and ESPHome packages are published open source on GitHub.

HomeMaster printed circuit boards at bare-board and populated assembly stages

HomeMaster modules on a bench test rig with automated test equipment

Eleven modules have been taken through EU conformity assessment for EMC, LVD, RED and RoHS, with Declarations of Conformity issued for each. The electrical-safety and EMC test capability built for that work is described under Compliance and Testing.

Open source and documentation

Hardware, firmware and ESPHome YAML for every module are on GitHub. Modbus register maps, integration examples for Home Assistant and application notes are on home-master.eu.

The online configurator lists the exact modules, enclosure size and DIN-rail layout for a described installation, with live shop prices — see Build your system on the brand site.