Guides
Practical guides for connecting, configuring and monitoring Modbus devices.
Modbus Protocol: History, Origin, and Why It Still Runs
The Modbus protocol explained: how Modicon created it in 1979, why it became open in 2004, and what that history means for you on the bus today.
Viessmann heat pump Modbus: an installer's guide for 2026
Read Viessmann Modbus through the Vitogate 300: which Vitocal speaks Modbus, the dynamic register assignment, wiring step by step, plus COP and SG Ready over Modbus for installers.
Loxone Modbus setup: HVAC over RTU and TCP (2026)
Loxone Modbus setup for HVAC. Modbus Extension (RTU) versus Modbus TCP, configuring a sensor in Loxone Config, wiring, and troubleshooting.
Huawei SUN2000 Modbus: read it over Modbus TCP
Huawei SUN2000 Modbus over Modbus TCP: enable it in the app, poll on port 502 at unit ID 1, and scale the Huawei registers correctly.
Modbus register map explained: how to read any device map
Modbus register map explained for installers. The four register types, Modicon vs wire addressing, 32-bit word order, and a worked Eastron SDM630 example.
4G Modbus Gateway: Connectivity for Remote Sites (2026)
A 4G Modbus gateway sends RS485 data to the cloud over LTE. Which class to pick, how much SIM data you need, failover, and staying secure without a public IP.
SunSpec Modbus: one register map for many inverters
SunSpec Modbus is the open register map SMA, Fronius, SolarEdge and Kostal share. Learn the layout, int+SF vs float, ports, and reading a mixed fleet.
Modbus home automation integration guide
Modbus home automation explained: where Modbus fits beside KNX, BACnet, and EEBUS, the platforms that read it, and the five integration paths.
Fronius Modbus: read a Symo GEN24 over Modbus TCP
Fronius Modbus explained: enable Modbus TCP on the Symo GEN24 on port 502, choose between int+SF and float, read the right SunSpec registers and scale them correctly. Practical guide for solar installers.
Modbus Scanner: How to Scan a Modbus Network and Find Devices (2026)
A Modbus scanner finds slave addresses and serial settings on an unknown bus. Tools, the 1 to 247 address range, and the duplicate-address pitfall explained.
SMA Modbus: reading a Sunny Boy over Modbus TCP (installers)
SMA Modbus explained: enable the Modbus TCP server on port 502, choose between the SMA profile (unit ID 3) and SunSpec (unit ID 126), read the right registers, and handle the NaN values at night. Practical guide for installers.
Modbus TCP Gateway Setup: Step-by-Step Guide for Installers
Modbus TCP gateway setup in five steps: wire RS485, match serial parameters, static IP, Unit ID mapping and test. Covers port 502 and troubleshooting.
SolarEdge Modbus TCP: port 1502 and the SunSpec registers
SolarEdge Modbus for installers: enable Modbus TCP in SetApp on port 1502, the verified SunSpec register map with scale factors, the 502 trap, and how a gateway polls the inverter alongside the SolarEdge portal.
RS485 cable selection for Modbus: specs that actually matter
Pick the right RS485 cable for Modbus RTU: 120 ohm characteristic impedance, twisted pair, foil plus braid shield, and the CAT6 substitution question. Belden 9841, Alpha Wire and Lapp compared.
EV charger Modbus monitoring: an installer and CPO guide (2026)
EV charger Modbus monitoring for installers and CPOs. AFIR plus EnWG context, KEBA, Mennekes, Alfen and ABB brand matrix, step by step Modbus TCP commissioning.
Daikin heat pump Modbus: an installer's guide for 2026
Daikin heat pump Modbus monitoring for installers. EKMBDXB7V vs BRP069A78, the 21 Altherma 3 registers that matter, COP/SCOP derivation, SG Ready logging and how EU EPBD, MCS and Ecodesign use the data.
KNX to Modbus gateway: when and why for installers (2026)
KNX to Modbus gateway guide for installers. Weinzierl, Intesis and Gira compared, datapoint mapping examples, 2026 prices, and when to choose a gateway or an alternative.
Solar inverter monitoring with Modbus, installer guide 2026
Solar inverter monitoring with Modbus: read SMA, Fronius, KOSTAL, Huawei and SolarEdge via SunSpec, which registers matter and how a vendor neutral fleet view works.
Modbus function codes explained: a complete installer reference (2026)
Modbus function codes explained for installers. Read holding registers (0x03), write multiple (0x10), exception codes, and the 40001 vs 0x0000 trap.
F-gas digital logbook: what to record under EU 2024/573
F-gas digital logbook obligations under EU 2024/573 explained for refrigeration contractors. From the 5 t CO2-eq threshold to Modbus telemetry that feeds the logbook automatically.
Modbus alerts: a complete setup guide for installers (2026)
Modbus alerts setup without alarm storm. Thresholds, fault codes, offline detection, channels per severity, and record keeping under EU F-gas Regulation 2024/573. Practical for installers.
Modbus TCP explained: a guide for installers (2026)
Modbus TCP sends the same requests as RTU over Ethernet: port 502, a 7 byte MBAP header instead of a CRC, and no bus timing to get wrong. When to pick it.
Heat pump Modbus monitoring: an installer's guide (2026)
Heat pump Modbus monitoring for installers. Brand-by-brand interface map, the 21 registers that actually matter, COP derivation, SG Ready over Modbus, and what EU EPBD, F-gas and MCS require in 2026.
RS485 wiring for Modbus: a complete installer guide (2026)
RS485 wiring for Modbus explained: cable choice, length vs baud rate, A/B polarity, termination, shielding, and the field mistakes that break a bus.
Home Assistant Modbus integration: a complete installer guide (2026)
Home Assistant Modbus integration for installers. Three connection types compared, YAML examples for SolarEdge and Eastron, scan_interval guidance per device class, and when to step up to professional monitoring.
Modbus RTU explained: a complete guide for installers (2026)
Modbus RTU explained for installers. Frame structure, RS485 wiring, function codes, troubleshooting, and what the EPBD obligation from 2026 means.
What Is Modbus? A Complete Installer Guide for 2026
One device asks, another answers with bare numbers and no units. That single property explains registers, function codes, and most of what goes wrong on site.
F-Gas Regulation digital logbook: what you need to prepare by 2029
Complete guide for heat pump and HVAC installers on meeting the logbook requirements of EU 2024/573, with thresholds, deadlines and a practical migration plan.
NIBE heat pump Modbus: MODBUS 40 and register map
Wire MODBUS 40 to an F-series NIBE, switch on Modbus TCP for an S-series, and read the registers that matter. Addresses, scale factors and the usual faults.
RS485 wiring and Modbus RTU installation: the complete guide
Everything about RS485 cabling for Modbus RTU: cable selection, termination, A/B polarity, shielding, topology, and the top 10 wiring mistakes.