The ABB IPR/S3.5.1 KNX IP Router Secure connects the KNX twisted-pair bus to an Ethernet network while encrypting all IP-backbone traffic using the KNXnet/IP Secure protocol. Like the standard IPR/S 3.1.1, it occupies 2 modular spacings (2 MW) and functions as a fast line and area coupler with full filter-table support for main groups 0–31.

Security is built in: the device supports Secure Routing and Secure Tunneling with 5 Secure Tunneling Servers for encrypted ETS programming and client access over LAN. Power is supplied via 12 … 30 V DC or PoE (IEEE 802.3af class 1), with just 1.5 W power loss.

Key Features — KNX IP Secure, Routing, and Tunneling

Encrypted IP Backbone

• KNXnet/IP Secure: Encrypts communication on the IP network for both routing and tunneling.
• Secure Routing: Links KNX lines/areas across the LAN with encrypted telegrams.
• Secure Tunneling: 5 Secure Tunneling Servers for encrypted ETS access and visualization clients.
• Filter table: Full main-group filtering (0–31) for efficient bus loading management.

Network and Installation

• IP addressing: Fixed IP or DHCP allocation.
• Multicast / Unicast: Standard KNX multicast can be switched off; up to 10 IPR/S 3.5.1 devices support unicast communication.
• Compact MDRC: 2 MW DIN-rail module — 36 × 90 × 64.5 mm.
• Dual power: 12 … 30 V DC auxiliary or PoE (IEEE 802.3af class 1).

At a Glance

Specification	Detail
Product type	KNX IP Router Secure — KNXnet/IP Secure
Order code	IPR/S3.5.1 (2CDG110176R0011)
Security protocol	KNXnet/IP Secure — Routing and Tunneling
Secure tunneling servers	5
Coupler function	Fast line and area coupler; filter table main groups 0–31
Power supply	12 … 30 V DC or PoE (IEEE 802.3af class 1)
Power loss	1.5 W
Dimensions (W × H × D)	36 × 90 × 64.5 mm (2 MW)
Protection	IP20

Full electrical ratings, ordering codes, and classification data are listed under Technical Specifications. Technical data, secure commissioning guides, ETS application, CAD, and EPLAN data are under Downloads.

Applications and KNX Integration

• Security-sensitive buildings: Encrypt KNX IP traffic in offices, hotels, and critical infrastructure where IT security policies require KNX IP Secure.
• Multi-line IP backbone: Bridge KNX segments over encrypted Ethernet without compromising telegram confidentiality.
• Remote secure commissioning: Use Secure Tunneling for ETS access from authorised clients on the LAN.
• ETS configuration: Import the official .knxprod application (Downloads), configure security keys, filter table, and tunneling endpoints per the secure commissioning guide.
• Power planning: When not using PoE, supply auxiliary power from an ABB KNX power supply such as the SV/S 30.640.3.1 KNX Power Supply 640 mA.

Choosing IP Routers and Line Couplers

For installations where standard (non-encrypted) KNXnet/IP is sufficient, choose the IPR/S3.1.1 KNX IP Router. For TP-side line segmentation with KNX Data Secure and electrical isolation, use the LK/S 4.2 KNX Line Coupler.