The Interra ITR403-1001 is a ceiling-mounted KNX smoke + heat detector that senses typical fire indicators and publishes alarm telegrams on the KNX bus. Powered only from the bus (approx. 2.8 mA standby / 7.6 mA alarm), it needs no separate mains supply. An internal sounder starts on high temperature, smoke or fire emergency; when smoke exceeds the threshold, the device can notify touch panels or mobile clients through the KNX infrastructure.

Two relay outputs are available (1 A @ 30 V DC / 0.25 A @ 230 V AC). Twist-lock head-to-base mounting and a tamper-resistant design simplify install and service. Under normal residential/hotel conditions one device covers about 40 m²; recommended spacing is ~6.3 m. Programming mode is entered with a magnet at the reed relay. Pair flood detection via ITR401-0001 for a fuller risk stack.

Key Features — Smoke + Heat on KNX

• Dual sensing: Smoke chamber + heat; local siren on emergency.
• Bus-only power: No auxiliary PSU; KNX certified / ETS.
• Two relays: Auxiliary contacts for panels, bells or plant logic.
• ~40 m² coverage: ~6.3 m spacing in normal ceiling conditions.
• Twist-lock base: Fits common octagonal / round / square junction boxes.
• IP44: 100 × 50 mm (Ø × H) light-grey housing; −30…50 °C operation.

At a Glance

Specification	Detail
Order code	ITR403-1001
Product type	KNX Smoke + Heat Detector
Current	2.8 mA standby · 7.6 mA alarm
Relays	1 A @ 30 V DC · 0.25 A @ 230 V AC
Coverage (typical)	~40 m² · ~6.3 m spacing
Dimensions (Ø × H)	100 × 50 mm
Protection	IP44
Configuration	ETS · magnet reed programming

Applications and Related Products

• Residential / hotel ceilings: Early fire indication into KNX panels and servers.
• Leak detection: ITR401-0001 or conventional ITR400-0001.
• Presence / lighting: ITR415-0003 wide-range multi-sensor.
• Visualisation: Interra iX panels or building servers for alarm routing.

Choosing and Commissioning

Mount on ceiling ≥15 cm from walls (or wall-mount 10–30 cm below ceiling). Wire KNX+ to terminal 5, KNX− to 2, relays to 3 and 6 (terminals 1 and 4 unused). Twist the head clockwise onto the base. Use a magnet on the reed for programming mode, then load the official .knxprod. High-bay / warehouse coverage may shrink with height — see datasheet notes under Downloads.