How to Scan a KNX Bus Line

A line scan asks every individual address on a KNX line whether a device is there and lists every device that answers. It shows what is actually installed, independent of any ETS project - the fastest way to get an overview of an installation, check it against the project, or find a device you are looking for.

SharKNX scans twisted pair (TP), IP, and IoT lines, and - with an ETS project - powerline (PL) and radio (RF) domains.

Device tools, including line scans, are a premium feature on Android, iOS, and macOS - see Subscription Plans.

Before you start

• Connect to a KNX gateway - see Connect to a Gateway.
• Know the area and line you want to scan, e.g. 1.1. With an ETS project loaded, you can pick it from a list instead.

Scan a line

1. Open Tools → Line Scan.

2. In the Scan Settings card, set:

   Setting	Description
   Area / Line	The line to scan, e.g. area 1, line 1. Or tap Choose from project to pick a line from your ETS project - this also sets the medium.
   Medium	The line's medium: TP, IP, or IoT when entered by hand. PL and RF are set by picking the line from your project - see below.
   Scanning Range	The device addresses to scan, From 0 To 255. Narrow the range to scan faster or to check part of a line.

3. Tap the scan button. You can stop the scan at any time.

4. Devices appear as cards as they answer. The coloured bar at the top of each card shows its type:

   Colour	Device
   Green	KNX Data Secure device
   Blue	IP device or coupler
   Red	Any other device

Each card shows the device's address and what SharKNX could read of its type. To fill in manufacturer, serial number, and the rest for every device at once, tap Read Device Info above the list once the scan is done.

Scanning another line works through the line and area couplers, so it takes longer than scanning the line your gateway is on - SharKNX then asks each address individually instead of relying on the bus confirmation.

Scan a powerline (PL) or radio (RF) domain

Powerline (KNX PL110) and radio (KNX RF) devices don't share a cable - they are grouped by a Domain Address that keeps neighbouring installations apart. To reach the devices, a scan has to know that domain address, and it is stored in the ETS project.

1. Load your ETS project - see Load an ETS Project.
2. In Tools → Line Scan, tap Choose from project and pick the PL or RF line. SharKNX fills in the area, line, medium, and domain address from the project.
3. Tap scan.

PL and RF can't be selected by hand, because a manually entered line has no domain address. For RF, SharKNX uses the scan procedure the KNX standard defines specifically for radio, where devices answer with their descriptor directly. Found devices show their Domain Address in the device details.

You need a gateway or media coupler that can reach the PL or RF medium.

Scan an IP line

For a KNX IP line, choose IP as the medium. When you are connected through multicast routing, SharKNX finds the devices with a KNXnet/IP discovery search on the backbone instead of asking every address - faster, and it only lists devices on the line you asked for.

Work with a found device

Tap any card to open its sheet:

• Check - confirm the device still answers
• Read Info - read manufacturer, model, serial number, firmware, run state, and table states
• Prog. Mode - switch programming mode on or off remotely
• Restart - restart the device
• Program Address - give the device a new individual address, by programming button or by serial number - see Program a Device Address
• Rebuild Communication - open the device in Tools → Inspect to read its communication objects - see Inspect a Device

Export the results

Open ⋯ Actions to export the latest scan:

• Export as Text - a TXT report with the scan settings, gateway, and every device with its details
• Export as PDF - the same report as an A4 PDF

Both formats are described in Export Formats. Tap Read Device Info before exporting to get the full details for every device.

What a line scan is good for

• Taking over an installation - build an inventory of what is really installed, then export it as a PDF for your records.
• Checking against the ETS project - spot devices that are missing, answer at an unexpected address, or should not be there.
• Commissioning - find new devices still at 15.15.255 and program their addresses straight from the scan.
• Finding a device - scan the line, then use Prog. Mode or Rebuild Communication to identify the one you need.

Troubleshooting