---
lang: "en"
title: "KNX USB Interface 312.1"
sku: "5501"
canonical_url: "https://shop.marcomweb.it/en/konnex/knx-usb-interface-3121"
brand: "MARCOM S.r.l."
end_of_life: "false"
---

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KNX USB Interface 312.1

The KNX USB Interface 312.1 is a data interface between a PC or laptop and the KNX installation bus. The device can be used as a programming interface for the ETS® software and supports KNX Long Frames. Long telegrams allow faster downloads to devices that support such telegrams, and it is necessary for KNX Security.

LEDs on the device indicate the operating status and communication errors on the bus. The USB connector (USB C) is galvanically isolated from the KNX bus.

#### Note for Developers

KNX USB communication is based on HID and cEMI telegram encoding in accordance with the KNX specification. To integrate the KNX USB interface into applications running on Windows or Linux, Weinzierl's cross-platform kDrive SDK is available. In addition to the interface for telegrams via cEMI, the KNX USB Interface 312.1 includes a complete KNX Stack with communication objects and BAOS V2 protocol. In this way, the device offers the possibility to extend devices with a USB connection (e.g. boards with embedded Linux) into complete KNX devices, which can even be programmed with ETS.

## Technical Features

- Protection class (according to EN 60529): IP20
- Operating ambient temperature: - 5 … + 45 °C
- Non-operating ambient temperature: - 25 … + 70 °C
- Relative humidity (non-condensing): 5 … 93 %
- Enclosure: plastic (PC)
- Device for DIN rail mounting, width: 1 module (18 mm)
- Indicators: 3 LEDs, multicolor

#### KNX

- Transmission medium: TP (Twisted Pair)
- Interface protocol: HID/cEMI
- Maximum APDU length: 233
- Object Server: BAOS V2
- Device model: System B

#### Power Supply

- USB < 15 mA
- KNX < 3 mA

#### Connectors

- Connector for KNX TP bus (red/black) USB: type C connector, maximum cable length: 5 m

 

- Weight: approx. 40 g

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Source: https://shop.marcomweb.it/en/konnex/knx-usb-interface-3121

MARCOM S.r.l. — a trusted supplier for industrial automation and building automation.