Comelit is Italy's largest video door entry manufacturer with 60+ years of production history. The VIP (Video IP) system is the current flagship — 2-wire bus architecture, SIP-compatible IP door stations, and a KNX integration module (1456B) that bridges door events to the KNX installation. This guide covers the 1456B module wiring, ETS6 group address assignment, gate automation relay integration, and multi-tenant building configuration.

Comelit VIP 2-wire bus architecture

The Comelit VIP system uses a single YCYM 2×0.75mm² (or equivalent unshielded 2-wire) cable to connect all components: door station (SP) → switchboard (SW) → monitor units (M). The 2-wire BUS carries audio, video (analogue, 4MHz bandwidth), power (18V DC from switchboard PSU) and data on the same pair — eliminating multi-cable runs. Switchboard: Comelit 1082 (1 line, 4 monitors), 1082/4 (4 lines, 32 monitors). Each VIP system has one switchboard per building entrance. Max bus length: 100m from switchboard to furthest monitor without repeater, 200m with Comelit 6743 bus repeater. Door station: Comelit 6741W (ultra-slim, 1-button, IP65, IK10), Comelit 6742W (2-button), 6513W (vandal-resistant granite). IP connection: Comelit 6741W has RJ45 port for SIP extension to mobile app (Comelit ViP app) — simultaneous bus and IP operation.

1456B KNX interface module wiring

The Comelit 1456B is a DIN-rail module (4 modules wide, 24V DC supply from KNX bus or external) that connects to the Comelit VIP bus on one side and the KNX TP bus on the other. Connections: VIP bus terminals BUS+ and BUS- (2-wire from switchboard secondary output), KNX terminal block (KNX+ red, KNX- black, GND green, from standard YCYM KNX cable). Individual address: ETS6 programming button on 1456B — standard KNX addressing. The 1456B must be wired in parallel on the VIP bus (not in series) — connect BUS+ and BUS- to the secondary output of the switchboard (not the door station line). Power: the 1456B draws bus current from the VIP switchboard (max 50mA) and separately from the KNX bus (40mA). Total VIP line load must be within switchboard PSU capacity.

ETS6 application and group object assignment

Comelit provides an ETS6 .knxprod application file downloadable from comelit.eu. Import to ETS6 catalogue, drag 1456B into topology. Group objects: (1) Door call (DPT 1.001) — 1-bit, sends 1 when door button pressed. Link to GA e.g. 12/0/0. (2) Door open output (DPT 1.001) — 1-bit, write to open door relay. Link to GA 12/0/1. (3) Call active (DPT 1.001) — 1 while call in progress. (4) Monitor pickup (DPT 1.001) — 1 when monitor answers. (5) Service (DPT 1.001) — DND/do not disturb flag from KNX (hotel card reader → KNX → 1456B service input suppresses bell). Parameters: ring time (5–30 seconds, default 30), door open pulse duration (0.5–10 seconds, default 3 seconds), enable/disable individual group objects. KNX logic example: 12/0/0 (Door Call) → KNX switch actuator GA 5/2/1 (Entrance Lighting, send 1) — arrivals automatically illuminate entrance.

Gate relay integration

In residential projects with an automatic gate, the KNX installation can control gate open/close from a KNX push-button, smartphone, or time schedule — integrated with the Comelit system for visual confirmation. Gate hardware: Came BXV gate operator with relay board (CAME 001RE432 radio receiver, or direct relay). KNX wiring: KNX 2-channel binary output module (MDT, Gira, or ABB) relay output → gate relay coil (24V DC or 230V depending on gate model). ETS6 logic: KNX push-button (GA 12/1/0, DPT 1.001) → KNX switch actuator (GA 12/1/0) → relay output ON 3 seconds → relay OFF (pulse activation). Comelit integration: 1456B door open output (GA 12/0/1) → linked to gate relay GA 12/1/0 via ETS6 scene or direct group send — pressing door button on monitor sends door open GA → simultaneously opens gate. CCTV confirmation: Axis camera on entrance → VAPIX event trigger when Comelit call GA = 1 → camera moves to entrance preset position and records.

Multi-apartment building configuration

For a building with 24 apartments, 1 entrance: Comelit VIP switchboard (Comelit 1082/4, 4 lines) → up to 32 monitors (one per apartment). Each apartment monitor: Comelit 6721W (7" colour monitor, 2-wire BUS connection). ETS6 configuration for KNX integration: one 1456B per entrance → single door call GA for all apartments (building-wide entrance lighting automation). For individual apartment call detection (which apartment was called): use Comelit 4-wire RS485 port on switchboard → Comelit manager software (PC) → REST API → Home Assistant → publishes per-apartment call events to MQTT → KNX IoT gateway or IP-Symcon sends KNX telegram for per-apartment lighting. Simpler alternative: each apartment has its own monitor with built-in relay output (Comelit 6721WR) — relay directly wired to KNX binary input in apartment distribution panel.

Comelit ViP cloud app integration

The Comelit ViP mobile app (iOS/Android) allows remote answering of door calls and remote door opening via 4G — no KNX required for the app, but KNX can trigger app notification. Configuration: Comelit 6741W door station registered in Comelit ViP cloud (account.comelihome.it) → SIP extension assigned → app receives push notification on incoming call. KNX trigger for app: 1456B door call GA (12/0/0) → Home Assistant → Comelit ViP API call (REST, documented at comelit.eu/developer) → sends push to additional mobile devices not registered as SIP extensions. App remote door open: Comelit ViP app → ViP cloud → SIP command → door station relay. Latency: 1–3 seconds typical on 4G. Do not rely on cloud app for security-critical access — always retain local hardware (key cylinder, keypad) as backup.