Parameter Category Specification System / Standard KNX / EN 50090, ISO/IEC 14543 Bus Voltage 21 – 32 V DC (KNX SELV) Auxiliary Supply (Us) 24 V AC/DC, SELV (Typical for valve actuators and fan speed relays) Core HVAC Control Functions • Room Temperature Control: Compares measured room temperature (via integrated or external sensor) with setpoint. • Fan Speed Control: 3-speed (High/Med/Low) or 4-speed (including Auto) via relay outputs. • Valve Control: Modulating control of water valves via 0-10V analog outputs for precise flow regulation in 2-pipe or 4-pipe systems. • Operating Mode Selection: Auto, Comfort, Standby, Frost Protection, etc. Inputs & Sensors • Integrated Room Temperature Sensor (likely due to E suffix). • Binary Inputs (AB): For window contacts, presence detectors, local push-buttons. • Optional External Sensors: Can connect to external temperature sensors (e.g., floor sensor) via KNX or analog input. Outputs • Analog Outputs (AE): 2 channels of 0-10V DC for controlling heating valve and cooling valve actuators (in a 4-pipe system). • Relay Outputs (AG): Typically 3 or 4 relays for fan speed control (High, Medium, Low, possibly Off). Each relay rated for fan motor load (e.g., 5(2)A @ 230V AC). • Additional Auxiliary Relay: May include one for On/Off valve or summer/winter changeover. KNX Communication • Sends room temperature, operating mode, fan speed, valve position, alarms. • Receives setpoints, mode commands, schedules from higher-level systems. • Can be part of energy management scenes (e.g., night setback). User Interface Likely includes a basic local display (showing temperature/setpoint) and buttons for manual override (if E indicates this feature). Configuration Exclusively via ABB ETS (Engineering Tool Software). Extensive parameters for: PID control loops, valve characteristics, fan speed logic, interlock with window contacts, hysteresis, etc. Mounting 35 mm DIN Rail in a distribution board, typically located near the fan coil unit. Typical Wiring Connects to: KNX bus, 24V AC/DC power supply, fan motor terminals, valve actuator cables, window contact, and optionally an external temperature sensor.