Digital I/O module FBB-4DI2DO.R

RS-485Modbus RTU4-I

Product overview
The FBB-4DI2DO.R.xxx interface module provides four digital inputs and two relay outputs designed for decentralized switching tasks. It is suitable for controlling up to two motor-driven fire dampers (BSK) with feedback (end-switch OPEN/CLOSED), or for general remote I/O data points in HVAC and fire-safety control systems.

Measured run-time monitoring
The module supports measured run-time monitoring for motor-driven BSKs. Run times are captured on every actuator operation to determine total opening and closing durations and to measure dead time (the delay until the device reports departure from its initial position). Measured values are compared against maximum reference values configured during commissioning to detect deviations.

Variants and options
The FBB-4DI2DO.R.xxx family (also FBB-2DI1DO.R.xxx) is available in multiple variants and options:

• Supply voltage: 24 V or 230 V. In the R.230 variant the supply voltage is used as the relay output feed (line L = 230V is switched to the digital output via the relay contact).
• Option "AMP": module variants with AMP pluggable sockets to accept prefabricated cables/connectors commonly supplied with BSK actuators.

Applications
Designed for decentralized switching and monitoring in ventilation and fire-protection applications. Typical uses include actuation and runtime monitoring of motor-driven fire dampers (BSK) and implementation as distributed remote I/Os in building automation networks.

Technical specifications

• Manufacturer: romutec Steuer- und Regelsysteme GmbH
• Product number / SKU: 00003219
• Model/Series: FBB-4DI2DO.R (series FBB-4DI2DO.R.xxx)
• Inputs: 4 digital inputs
• Outputs: 2 relay outputs
• Relay rating (R.230 variant): uses supply voltage as output signal (L = 230V switched via relay contact); relay current rating 16 A
• Supply options: 24 V or 230 V
• Option: "AMP" = variants with pluggable AMP sockets for prefabricated BSK cables
• Intended use: control of up to two motor-driven fire dampers (BSK); general decentralized data points / remote I/Os
• Functions: run-time measurement (open/close), dead-time measurement, comparison with configured maximum reference values
• Compatible variants: FBB-2DI1DO.R.xxx and other FBB series variants
• Weight: 0.465 kg
• Release date (meta): 2026-04-28