Busch-Jaeger KNX Binary Input 4-Channel Flush-Mounted BI-F-4.0.12 2CDG510024R0021

In modern KNX building automation, integrating conventional switches, push-buttons, or potential-free contacts is a common requirement. The Busch-Jaeger KNX Binary Input 4-Channel Flush-Mounted BI-F-4.0.12 (2CDG510024R0021) enables exactly that: it reads up to four binary signals from external contacts and converts them into KNX telegrams for controlling lighting, blinds, or other functions. Installed in a standard flush-mounted box, it fits discreetly behind a conventional switch or push-button, making it ideal for retrofits and new installations alike.

Key specifications

• System compatibility: KNX
• Number of inputs: 4
• Input type: Binary (potential-free contacts)
• Mounting type: Flush-mounted (UP)
• Power supply: Via KNX bus
• Bus voltage: 21-30 V DC (KNX)
• Current consumption (KNX): Max. 5 mA
• Connection terminals: Screwless terminals for inputs, KNX bus terminal
• Max. input cable length: 10 m
• Configurable functions: Switching, dimming, blind control, value transmitter, scene recall, counter, sequence controller
• Operating temperature: -5 °C to +45 °C
• Protection class: IP20
• ETS software requirement: ETS4.2 or higher
• Housing material: Plastic
• Installation location: Standard flush-mounted box (e.g., Ø 60 mm)

Why choose it

This binary input offers high flexibility: each channel can be independently configured in ETS to trigger various KNX functions. Its compact flush-mounted design allows integration into existing switch boxes without additional space. The screwless terminals simplify wiring, and the device is powered directly from the KNX bus, eliminating the need for an auxiliary power supply.

Ideal use cases

• Connecting conventional light switches or push-buttons to a KNX system
• Integrating window contacts, door contacts, or other potential-free sensors
• Retrofitting existing installations where no separate KNX input module is available
• Implementing multi-function control (e.g., long press for dimming, short press for switching)

Good to know

The device is part of the Busch-Jaeger KNX series and requires ETS4.2 or higher for configuration. It is designed for indoor use only (IP20). The maximum cable length per input is 10 meters, which should be considered when planning the installation.