ABB free@home is ABB's proprietary home automation platform — simpler than KNX but built on the same KNX TP physical bus. The System Access Point (SAP 2.0) acts as the central intelligence, replacing ETS6 with a browser-based app interface that residential installers can configure in hours rather than days. This guide covers complete commissioning from SAP installation through to KNX gateway setup for hybrid free@home + KNX installations.

System Access Point 2.0 installation

The SAP 2.0 (SAS/A 2.1.1) is a DIN-rail device (2 modules wide) with: KNX TP screw terminal, RJ45 Ethernet port (connects to LAN for app access and cloud), 24V DC power input (or powered from KNX bus if bus current budget allows). DIN-rail installation: mount SAP 2.0 in main distribution panel alongside KNX PS640. Connect KNX bus (red + / black -), Ethernet Cat5e patch cable to router, and 24V DC supply if needed. Factory default IP: DHCP. Find SAP IP from router DHCP lease table or scan with network scanning tool. Browser access: http://[SAP_IP] → ABB-free@home app login (default username: installer, password: on label). First setup wizard: set system name, time zone, network settings (recommend static IP for SAP: avoids app reconnection issues after router DHCP lease renewal).

Device discovery and assignment

After SAP setup: App > Devices > Search for devices. SAP scans the KNX TP bus, discovers all free@home devices by their factory individual addresses. Each device appears with its type (switch actuator, dimmer, room controller) and a default name. Assignment: for each device in the discovery list: tap device > assign to room (create rooms: Living Room, Bedroom 1, Kitchen, etc.) > confirm. Physical identification: App > device > flash LED — the device LED flashes for 10 seconds on the corresponding unit in the panel or on the wall. Verify each device is in the correct room before proceeding. Individual address assignment: the SAP assigns free@home individual addresses automatically — installers do not program KNX individual addresses manually (unlike KNX ETS6).

App configuration — scene creation

free@home scenes are created visually in the app: App > Scenes > New Scene > assign name (e.g. "Dinner") > add actions: device (living room dimmer) = 60%, device (kitchen switch) = ON. Trigger: scene can be triggered by keypad button (assign keypad button to scene), time schedule (App > Time programs > create schedule), or voice command (via Alexa/Google Home cloud connection). Multiple scenes per room: create "Morning" (all 100%), "Evening" (living 70%, kitchen off), "Night" (all off), "Away" (all off + simulated presence timer). Timer programs: App > Time programs > set weekly schedule for heating setpoint, lighting scenes — replaces ETS6 logic blocks for basic residential timer functions. Note: free@home timer programs have limited logic compared to ETS6 (no astronomical clock, no complex conditions) — for advanced timer logic, use the KNX gateway with a KNX IP router and ETS6 logic.

HVAC integration

ABB free@home room thermostat (RTH/A): DIN-rail or flush-mount room temperature controller with display, KNX TP bus. In free@home app: assign to room, set comfort temperature setpoint (default 21°C), set economy setpoint (default 18°C). Presence-linked HVAC: if room controller with presence input is installed: App > Function > Room temperature controller > presence signal = from [binary input device] > enable presence-linked economy mode. When presence input = 0 (no one home) → economy setpoint. When presence = 1 → comfort setpoint. Without a KNX presence sensor: use time program (economy 11pm-6am, comfort 6am-11pm). Fan coil unit integration: free@home does not natively support Modbus or 0-10V fan coil control — for FCU integration in free@home projects, use the FGA/A 1.1 KNX gateway to pass free@home thermostat setpoint to a KNX actuator controlling the FCU via Zennio KLIC-DD Modbus gateway.

FGA/A 1.1 KNX gateway configuration

For hybrid free@home + KNX installations — e.g., free@home switch actuators in all rooms, KNX DALI gateway for living room feature lighting: install FGA/A 1.1 (DIN-rail, 2 modules) on KNX bus. In free@home app: Devices > FGA/A 1.1 > Configuration. The gateway has 64 virtual channels (32 inputs from KNX, 32 outputs to KNX). Output channel setup (free@home signal → KNX): for each channel: set KNX group address (type GA number manually, e.g. 1/1/0), set DPT (1-bit, 1-byte, 2-byte float). Example: output channel 1 = living room dimmer ON/OFF (free@home scene state → KNX GA 1/1/0 DPT 1.001). Input channel setup (KNX → free@home): KNX presence detector (native KNX device) → KNX GA 0/1/0 DPT 1.002 → FGA/A 1.1 input channel 1 → free@home binary input function → triggers free@home "Occupied" scene. Limitation: only 1 FGA/A 1.1 gateway per free@home SAP. Maximum 32 KNX input groups and 32 KNX output groups per gateway.

Common commissioning issues

1. Device not found in scan: check KNX bus polarity (red = +, black/blue = -). Verify PS640 voltage at bus bar (28-31V DC). Verify device LED is on (powered from bus). If bus shows correct voltage but device not found: check device is in factory reset (hold button 5+ seconds to reset). 2. App cannot reach SAP: check SAP Ethernet LED (should be green). Verify SAP and laptop/phone on same LAN subnet. If SAP IP changed (DHCP lease renewal): use router lease table to find new IP, then assign static IP. 3. Scene activates wrong device: verify room assignment in app — device assigned to wrong room receives scene commands for that room. Re-assign device to correct room. 4. FGA/A 1.1 KNX signal not reaching KNX actuator: verify ETS6 group address on KNX actuator matches the GA entered in free@home FGA/A 1.1 output channel (exactly, with correct main/sub/address format). Check KNX actuator is receiving correct DPT format.