---
title: "Can’nX glossary: KNX group address, DPT, Modbus, kW and kWh"
description: "KNX group and physical addresses, DPT, ETS, Modbus register, trigger, kW vs kWh vs kVA: plain definitions of the terms used in the Can’nX guides."
canonical: https://wiki.can-nx.com/en/guides/customer-glossary/
language: en
product: nX platform
audience:
  - utilisateur
  - administrateur
  - installateur
context: "All Can’nX applications: context and rights, KNX and Modbus, automations, units and exports"
---

# Can’nX glossary: KNX group address, DPT, Modbus, kW and kWh

Context: All Can’nX applications: context and rights, KNX and Modbus, automations, units and exports

KNX group address, DPT, Modbus register, trigger, kW or kWh: here is what the terms used in the Can’nX guides mean, for users, administrators and installers. The exact labels of each screen are still given in the product guide.

## Identify your context and your rights

| Term | Definition |
| --- | --- |
| **Project, site, building** | Reference points that identify the installation you are working on. Their organization depends on the product: these words do not refer to the same level everywhere. Check the name displayed before changing a configuration. |
| **Gateway** | Device or connection point through which a Can’nX application communicates with the installation, for example a Kloud’nX gateway. In Link’nX, the project and the gateway displayed identify the open context. The word also refers to the Chart’nX Modbus gateway, which has its own settings, and to the Link’nX [KNX gateway table](https://wiki.can-nx.com/en/guides/link-gateway-table/), which maps a device’s functions to group addresses. |
| **Supervision / hypervision** | In Boss’nX, supervision presents one building; hypervision gives a consolidated view of several supervisions, within the authorized scope. Each one opens with its own link: see [signing in to Boss’nX](https://wiki.can-nx.com/en/guides/boss-access/). |
| **Role, permission, scope** | A role groups permissions and the scope they apply to. Viewing, controlling and administering are distinct permissions. Read the details of a role’s permissions rather than its name: see [Boss’nX roles](https://wiki.can-nx.com/en/guides/boss-roles-consult/). |
| **License / option** | Right to use a feature or an integration, distinct from a user’s permissions. In Link’nX, a padlock on a device card indicates a license that is not shown as active. For a missing option or its terms, follow the [support requests guide](https://wiki.can-nx.com/en/guides/customer-service/). |

## Configure and check a device

| Term | Definition |
| --- | --- |
| **KNX** | Open communication standard for building automation. The bus devices exchange commands, states and measurements through group addresses. The address and the data type entered in a Can’nX application must match the objects planned in the KNX project. |
| **KNX group address** | Logical address shared by the objects that take part in the same function, for example the push buttons and the actuator of a lighting circuit. It is usually written in three levels, as in the Can’nX applications: main group from 0 to 31, middle group from 0 to 7, subgroup from 0 to 255. **1/2/3** is a fictitious example, not to be copied: use the address from the ETS project. It is not an IP address. |
| **KNX physical address** | Address specific to one bus device, also called the individual address, in the area.line.device format, for example 1.1.5: area and line from 0 to 15, device from 0 to 255. It identifies a device, the group address a function. Boss’nX uses it to [monitor whether a device is reachable](https://wiki.can-nx.com/en/guides/boss-health-manage/). |
| **DPT — KNX data type** | The DPT (Datapoint Type) states how to read the value of a group address: format and unit. Examples: 1.001 switching (0 or 1), 5.001 percentage (0 to 100 %), 9.001 temperature (°C), 14.056 power (W), 13.010 energy (Wh). Use the DPT of the object defined in ETS: read with another DPT, the value is misinterpreted, even if the number has the right format. See [KNX measurements and commands](https://wiki.can-nx.com/en/guides/emergy-equipment-knx/). |
| **ETS** | KNX design and commissioning software, published by the KNX Association. The ETS project contains the group addresses and their DPTs. Its group address export, used by the Can’nX applications, must come from the installation’s project: see [the ETS file in Link’nX](https://wiki.can-nx.com/en/guides/link-knx-file/). |
| **Command / setpoint** | A command requests an action, for example on or off; a setpoint is the target value requested, for example a temperature. The appropriate value depends on the device’s function and its unit. A setpoint of **0** is a value, whereas an empty field may mean that no setpoint is entered. |
| **Status feedback / measurement** | Information received from the installation: the state of a device or a measured quantity. It is distinct from the command sent. It may be sent only in response to a KNX read request. To find out whether a command was executed, read this feedback or watch the device: a selected button or a saved configuration only shows the request. |
| **Auto / ON / OFF** | In Emergy’nX, **ON** requests forced operation, **OFF** a forced stop, and **Auto** hands control back to automatic operation: the device is therefore not necessarily on. See [the control guide](https://wiki.can-nx.com/en/guides/emergy-control/). |
| **Modbus, unit ID, register** | Communication protocol common on energy meters, over a serial link (RTU) or over IP (Modbus TCP). The unit ID identifies the device being queried. A register holds 16 bits; a 32-bit value takes up two. Depending on the manufacturer, numbering starts at 0 or at 1: use the address and the convention from its documentation, without shifting a register at random. See [the Modbus configuration](https://wiki.can-nx.com/en/guides/chart-modbus-config/). |

If the address, the DPT, the unit or the command value is not known, have it confirmed by the installer or by support before changing it. The format examples in this glossary are not recommended settings.

## Understand an automation

| Term | Definition |
| --- | --- |
| **Trigger** | Event that can request the start of a scenario, for example a set time or a KNX event. In Link’nX, several triggers are combined with OR logic: one is enough. |
| **Condition** | Criterion that must be met to allow an automatic start, for example a date, a time, day or night, a KNX value. In Link’nX, conditions are combined with AND logic. On its own, a condition starts nothing: a trigger is needed. |
| **Action / scenario** | An action describes an operation, such as sending a KNX value. A Link’nX scenario combines at least one trigger, optional conditions and an ordered list of actions. See [compose a scenario](https://wiki.can-nx.com/en/guides/link-compose-scenario/). |
| **Timer / delay** | Wait configured between an event and an action, or between two actions. The unit and range of the delay depend on the field: read its label. |
| **Load shedding / surplus optimization** | In Emergy’nX, load shedding reduces or cuts selected loads when the power drawn from the grid exceeds the defined thresholds; optimization switches on selected devices when a production surplus, for example solar, is fed into the grid. The [thresholds and commands](https://wiki.can-nx.com/en/guides/emergy-energy-thresholds/) are set for the installation concerned. |
| **Season / presence variant** | Set of settings for a state of the installation: Summer or Winter, Presence or Absence. Choosing its tab lets you edit it without forcing this state: the actual state comes from a signal configured for the building. See [the energy variants](https://wiki.can-nx.com/en/guides/emergy-energy-scenarios/). |

## Read values and exports

| Term | Definition |
| --- | --- |
| **Power: W / kW** | Rate of consumption or production at a given moment. **1 kW = 1,000 W**. Check the field’s unit before entering a value: in a field in W, 8 kW is written 8,000 W. |
| **Energy: Wh / kWh** | Quantity consumed or produced over a period, the one a meter records and the supplier bills. **1 kWh = 1,000 Wh**. The kW measures a rate, the kWh a quantity: at constant power, 1 kW for 1 hour gives 1 kWh (calculation example). |
| **Apparent power: kVA** | Power calculated from the voltage and the current, expressed in kVA, a unit often used for the subscribed power of an electricity contract. Active power in kW equals the apparent power multiplied by the power factor: the two values usually differ. Do not carry kVA over as is into a kW field. In Emergy’nX, **Max Apparent Power (kVA)** in the [power network](https://wiki.can-nx.com/en/guides/emergy-building-network/) expects the value of the grid connection. |
| **Off-peak / peak hours** | Periods of the electricity contract in which the price per kWh differs: reduced during off-peak hours, full during peak hours. Enter the times and prices from the site’s contract: a setting suggested in the form does not replace the contract. |
| **CSV** | Text file in rows and columns, separated by a character such as a semicolon or a comma, that opens in a spreadsheet. In Chart’nX, **Excel report** produces a CSV (semicolon, decimal comma), not an XLSX workbook. See [the export formats](https://wiki.can-nx.com/en/guides/chart-export-format/). |
| **Empty value / zero** | An empty cell or a missing measurement indicates that no value is available: it is not necessarily equal to zero. Check the meaning of the field and the product’s indications before calculating or changing a setpoint. |

## Contact support

Is a term, a unit or a value still ambiguous on your screen? Write to support@can-nx.com, stating the product and the label displayed.