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Sourced bank12 protocolsFree · no sign-up
KNX Basic
Sourced bankKNX Association
KNX Basic
Sourced bankKNX Association
By topic
System Overview
1TP Topology
4- 01On how many bits is the Group Address encoded inside a KNX TP1 telegram?HardQCM→
- 02The Group Address space in KNX TP1 allows up to 65 536 different Group Addresses (2^16).HardV/F→
- 03Within a KNX area, the maximum number of Line Couplers is 15, one per subsidiary line.MediumV/F→
- 04In an installation predating 2018, a maximum of 64 sensors, actuators, line couplers and backbone couplers can be connected to a TP main line.HardV/F→
ETS Project Design
1ETS Programming
3- 01The 'Reset Device' command in ETS performs a software restart of a KNX device without erasing its individual address or its application configuration.MediumV/F→
- 02A single Group Object can be associated simultaneously with several Group Addresses in ETS, which is typically used so that an actuator reacts to several commands (e.g. individual command + zone command + scene).MediumV/F→
- 03The programming button on a KNX product or the BCU has to be pressed to allocate the Group Addresses during the commissioning stage.MediumV/F→
KNX Advanced
Sourced bankKNX Association
KNX Advanced
Sourced bankKNX Association
By topic
Smart Metering
1HVAC Control
1Lighting Control
6- 01What is the principle of Constant Light Control regulation in KNX?HardQCM→
- 02Tunable White control (variable colour temperature, e.g. 2700 K warm to 6500 K cool) over KNX typically uses two distinct DPTs: one for the overall intensity (DPT 5.001, %) and one for the colour temperature (DPT 7.600, K).MediumV/F→
- 03A KNX presence detector configured with a 15-minute timeout keeps the lighting on for that duration after the last detection, then automatically switches it off.MediumV/F→
- 04The emergency lighting of a building CANNOT be driven by KNX alone: it must comply with dedicated standards (NF EN 1838, EN 50172) that require a self-contained system with a backup battery.HardV/F→
- 05DALI devices can be commissioned through the KNX/DALI gateway, typically using ETS apps or manufacturer-specific tools.MediumV/F→
- 06RGB control via KNX is typically performed with 3-byte colour telegrams (DPT 232.600).MediumV/F→
BACnet
Sourced bankASHRAE / BACnet International
BACnet
Sourced bankASHRAE / BACnet International
By topic
Practical
2- 01When an MS/TP segment is not working, the classic checks are: 120 ohm terminations at both ends, bias resistors (typically 680 ohm) installed on one device, a unique MAC per device, the same baud rate on every device, and correct cable polarity.HardV/F→
- 02The standard cable for BACnet MS/TP is an AWG 18-22 shielded twisted-pair with a 120 ohm characteristic impedance and capacitance below 30 pF/ft (98 pF/m), covering distances up to 1200 m at 9600 baud.MediumV/F→
Modbus
Sourced bankModbus Organization
Modbus
Sourced bankModbus Organization
By topic
Function codes
2- 01Which Modbus function code is used to READ the Holding Registers (16-bit read/write registers) of a slave?MediumQCM→
- 02Function 0x06 "Write Single Register" writes a single 16-bit Holding Register on a Modbus slave, with both the address and the value encoded on 16 bits each in the request.EasyV/F→
Practical
2- 01Modpoll (focus-sw.com) and mbpoll (Linux/macOS) are free command-line tools used to query a Modbus slave from a PC, indispensable for Modbus diagnostics and integration commissioning.MediumV/F→
- 02Modbus (RTU and TCP) has no native security: no authentication, no encryption, no signatures. The accepted good practice is strict OT VLAN isolation, an industrial firewall and no direct internet exposure.HardV/F→
PROFINET
Sourced bankPROFIBUS & PROFINET International
PROFINET
Sourced bankPROFIBUS & PROFINET International
By topic
Architecture
2- 01PROFINET defines three device roles: IO Controller (equivalent to the PLC master), IO Device (equivalent to a slave: sensor, actuator) and IO Supervisor (engineering PC used for diagnostics and configuration).EasyV/F→
- 02A GSDML file (Generic Station Description Markup Language) is provided by the manufacturer of a PROFINET IO Device and is imported into the engineering tool (e.g. TIA Portal) to integrate the device into the project.MediumV/F→
Diagnostics
2- 01LLDP (Link Layer Discovery Protocol, IEEE 802.1AB) lets PROFINET devices identify each other and automatically discover the network topology, which is exploited by diagnostic tools such as PRONETA or the TIA Portal Topology Editor.MediumV/F→
- 02PROFINET distinguishes several alarm types: "Process Alarms" (application events raised by the device), "Diagnostic Alarms" (detected hardware anomalies) and "Maintenance Alarms" (preventive maintenance needs).MediumV/F→
PROFIBUS
Sourced bankPROFIBUS & PROFINET International
PROFIBUS
Sourced bankPROFIBUS & PROFINET International
By topic
GSD files
2- 01A PROFIBUS GSD file (Generic Station Description) is a standardised ASCII file supplied by the device vendor; it contains the device characteristics (vendor, ident_number, supported baud rates, modules, parameters) needed to integrate it in the PLC project.MediumV/F→
- 02A compact PROFIBUS DP slave has an I/O configuration that is frozen at manufacturing time (e.g. a 32-bit encoder, a 4-module pressure transmitter), which simplifies configuration but limits flexibility.MediumV/F→
CMVP
Sourced bankEfficiency Valuation Organization
CMVP
Sourced bankEfficiency Valuation Organization
By topic
France context
3- 01ISO 50001 (Energy Management System) indirectly cites IPMVP as a good M&V practice in its clause 9.1 (monitoring, measurement, analysis), creating a natural bridge between organisational energy management and the individual CMVP certification.MediumV/F→
- 02OPERAT (Observatoire de la Performance Energetique de la Renovation et des Actions Tertiaires) is the official ADEME platform on which every building subject to the Decret Tertiaire must declare its annual consumption, from which compliance with the Crelat/Cabs targets is calculated.MediumV/F→
- 03For tertiary renovation projects in France, several public financing schemes (ADEME Fonds Chaleur, Plan de Relance, BPI Decarbonation loans) require multi-year M&V tracking of realised savings, creating structural demand for CMVP experts.MediumV/F→
Practical
2- 01To verify the savings from a Demand-Controlled Ventilation (DCV) retrofit in a tertiary building, IPMVP Option C with multiple regression including degree-days plus occupancy (measured through presence counters or badges) is typically the most appropriate approach.HardV/F→
- 02For a self-consumption photovoltaic (PV) installation, IPMVP proposes a modified approach: savings equal the PV energy consumed on site (self-consumption) plus the revenue from exported surplus, both quantified using two meters (PV production and grid import).HardV/F→
DALI-2
Sourced bankDALI Alliance
DALI-2
Sourced bankDALI Alliance
By topic
Architecture
2- 01DALI-2 (IEC 62386 Edition 2, 2014+) is the major evolution of DALI v1, adding native support for input devices (sensors, push-buttons) directly on the DALI bus itself, together with a product certification programme administered by the DALI Alliance (DiiA).MediumV/F→
- 02The DALI bus uses a polarity-free twisted pair (no + / - orientation), with Manchester coding at 1 200 baud over a nominal 22.5 V DC supply, and is allowed to share the same multi-core cable as the 230 V mains feeding the luminaires.MediumV/F→
Emergency DT1
3- 01A DALI DT1 Function Test simulates a 30-second mains outage to verify that the emergency luminaire switches over to battery; the result (OK / Battery Fault / Lamp Fault) is reported back to the controller for an EN 50172-compliant audit trail.HardV/F→
- 02The DALI DT1 Duration Test verifies the battery autonomy of an emergency luminaire by simulating a long mains outage (typically 1 h or 3 h depending on the EN 50172 category); a failure indicates an end-of-life or faulty battery that requires replacement.HardV/F→
- 03The DALI DT1 'Inhibit' (or 'Rest Mode') temporarily disables an emergency luminaire during planned building maintenance, avoiding spurious tests during the intervention; the gear returns automatically to normal mode after a timeout.MediumV/F→
OPC UA
Sourced bankOPC Foundation
OPC UA
Sourced bankOPC Foundation
By topic
Architecture
2- 01OPC UA supports two communication patterns: Client/Server (the classic Request/Response model) and Pub/Sub (publish/subscribe over MQTT or UDP multicast/unicast), the latter introduced in version 1.04 to address Industrie 4.0 use cases.MediumV/F→
- 02The OPC UA Address Space is a hierarchical structure of Nodes linked by typed References (HasComponent, HasProperty, HasTypeDefinition, etc.), exposed as a graph that clients can walk through the Browse service.MediumV/F→
Vendor implementations
2- 01Siemens S7-1500 (and S7-1200 V4.5+) PLCs embed a native OPC UA server that can be configured directly from TIA Portal: expose or restrict variables, set Security Mode and Policy, manage certificates, all without any additional hardware.MediumV/F→
- 02Ignition (Inductive Automation) is a modern SCADA/MES platform built around native OPC UA: it ships one integrated OPC UA Server plus drivers for 60+ protocols (BACnet, Modbus, KNX via gateway, Siemens S7, etc.), a web-based HMI and an MQTT IIoT Pub/Sub engine.MediumV/F→
Tools
2- 01UaExpert (Unified Automation) is the reference free OPC UA client for Windows, Linux and macOS: it browses the Address Space, reads and writes values, subscribes to changes, calls Methods and manages certificates, and is an indispensable tool for any OPC UA integrator.MediumV/F→
- 02node-opcua is the most popular Node.js (JavaScript) OPC UA implementation, used for fast prototyping, audit scripts and Web/MQTT/REST-to-OPC-UA integrations, and it is embedded in Node-RED and in many IoT projects.MediumV/F→
EnOcean
Sourced bankEnOcean Alliance
EnOcean
Sourced bankEnOcean Alliance
By topic
Architecture
1Matter
Sourced bankConnectivity Standards Alliance
Matter
Sourced bankConnectivity Standards Alliance
By topic
Device types
2- 01Matter Spec 1.0 already supports the core residential device types: OnOff Light, Dimmable Light, Color Temperature Light, Extended Color Light (RGB), Smart Plug, Door Lock, Contact Sensor, Motion Sensor, Window Covering, Thermostat and more.MediumV/F→
- 02A Matter device implements several Clusters (functional building blocks) according to its device type: OnOff Cluster for switching, Level Control for dimming, Color Control for RGB, and so on; each Cluster exposes Attributes for state readout and Commands for actions.HardV/F→
Bridge
2- 01The Matter Bridge pattern lets legacy devices (Zigbee, Z-Wave, KNX, EnOcean, proprietary protocols) be exposed as virtual Matter devices to a Matter ecosystem, by mapping their native features onto Matter Clusters.HardV/F→
- 02KNX-to-Matter bridges are emerging in 2026 (1Home, BAB Technologie, BootCloud): they expose KNX Group Objects as Matter devices (OnOff Light, Dimmable Light, etc.), letting residential KNX users add consumer Matter products without extra complexity.HardV/F→
LoRaWAN
Sourced bankLoRa Alliance
LoRaWAN
Sourced bankLoRa Alliance
By topic
Architecture
2- 01An important distinction must be made: "LoRa" is the physical-layer radio modulation (CSS, Chirp Spread Spectrum, proprietary to Semtech), whereas "LoRaWAN" is the MAC-layer protocol and network architecture (an open standard from the LoRa Alliance) built on top of LoRa.MediumV/F→
- 02LoRaWAN uses a "star-of-stars" topology: each end device transmits unidirectionally toward ALL in-range gateways, the gateways forward the packet to the Network Server, which deduplicates the copies; there is no mesh between end devices.MediumV/F→
Tools
2- 01The Things Network (TTN) is a free community LoRaWAN platform (community gateways plus a hosted Network Server) widely used for development, prototyping and maker-friendly deployments, with a web console and MQTT/HTTP SDKs for application integration.MediumV/F→
- 02ChirpStack is the most popular open-source LoRaWAN Network Server and Application Server (MIT licence) for private deployments, supporting LoRaWAN 1.0.x and 1.1, multi-tenant operation and a web UI plus gRPC/REST APIs.MediumV/F→
Network providers
2- 01As of 2026, the main public LoRaWAN operators in France are: Orange Live Objects (near-nationwide coverage), Bouygues Objenious (in sunset), Helium Network (community-driven) and Loriot (Swiss-based commercial Network Server vendor, not a public carrier). In addition, many deployments are run on private networks (dedicated infrastructure).MediumV/F→
- 02For critical IoT deployments (smart city, industrial sites, fleet asset tracking), private LoRaWAN networks are often preferred over public operators: full infrastructure control, contractual SLA, stronger security and no commercial dependency on a third-party operator.MediumV/F→
Use cases
2- 01Typical LoRaWAN smart-city use cases include: smart water meters, parking-bay occupancy sensors, fill-level sensors for waste bins, public-lighting telemonitoring, air-quality stations, EV charger monitoring (status and energy readings — not the OCPP charge-control protocol) and flood alerts — a typical LoRaWAN sensor costs between EUR 30 and EUR 150.MediumV/F→
- 02In building retrofits, LoRaWAN competes with EnOcean for energy sub-metering and wireless monitoring (temperature, CO2, presence): long range (one gateway covers a large building), 5-10 years of battery life on the sensors, but higher latency (Class A).MediumV/F→
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