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CR24-A3 Room temperature controller with 3 sequences AC 24 V Auto mode

On request
£125.33 £150.40

CR24-A3 Room temperature controller with 3 sequences AC 24 V Auto mode

•    Room temperature controller with 3 sequences
•    AC 24 V
•    Auto mode, without manual operation
•    Setpoint: 18...35º C
•    Temperature sensor: NTC internal 0, external: 10...45º C
•    5 inputs: EHO, Stand-by, (C/O / Boost / dewpoint),
•    0...10 V shift, ext. temperature sensor
•    3 outputs: VAV 0 / 2...10 V, heating 3-point,
•    Heating / cooling 0...10 V
•    Control characteristics: modulating, P-controller, P-Band switchable
•    Housing colour white RAL 9003
•    Base colour light grey NCS 2005 -R 80 B

More Information


Energy hold off: In energy saving mode, the room temperature is reduced to building protection level, i.e. eitherthe heating setpoint is significantly reduced or the cooling setpoint is significantly increased, forinstance in a room with an open window.

Stand-by: The room temperature is reduced to stand-by level, i.e. either the heating setpoint is slightlyreduced or the cooling setpoint is slightly increased, for instance in a room that is temporarily unoccupied.

Frost: The frost protection function is activated if the actual room temperature falls below 10°C.

Change-over: Change-over heating or heating/cooling.

Chilled ceiling with dew point limiting: Chilled ceiling with dew point limiting

Boost: The room can be ventilated with the maximum volume flow (max) or heated or cooled with themaximum capacity.

External temperature sensor: An external temperature sensor can be connected to the analog input ai1, for instance in orderto measure the average room temperature in the exhaust air duct.

External setpoint shift: An external DC 0...10 V signal at the analog input ai2 can be used to shift the basic setpoint0...10 K, for instance for the summer/winter compensation.

Manuals & Datasheets
Technical Information

•   Electrical data Nominal voltage AC 24 V 50/60 Hz
•   For wire sizing 3 VA, without actuators
•   Power supply range AC 19.2...28.8 V
•   Connections Terminal block 1...3: 2.5 mm2 Terminal block 4...8: 1.5 mm2
•   Functional data Control characteristics P / PI– P-band heating / cooling Selectable: 1.5 / 1.0 K or 3.0 / 2.0 K
•   External temperature sensor (ai1) Type NTC, 5 kΩ, sensing range 10...45°C for example Belimo type TFK
•   Heating setpoint Range 15...36°C (default 21°C)– Energy hold off Heating 15°C / cooling 40°C– Stand-by Heating –2 K / cooling +3 K
•   Dead band1 K
•   Frost limit temperature10°C
•   Operation (CR24-B.. only)– Mode switch and status indication (LEDs) AUTO (green) – ECO (orange) – MAX (red)– Rotary knob for setpoint adjustment±3 K
•   Communication port for field devices 2 x PP (for PC-Tool, MFT remote control etc.)
•   Inputs 2 x analog, 3 x digital– External temperature sensor (ai1)Type NTC, 5 kΩ, sensing range 10...45°C– External setpoint shift (ai2)0...10 V corresponds to 0...10 K–       Digital inputs (di1, di2)Contact rating 10 mA
•   Outputs 3 x analog– VAV system output (ao1) (0) 2 ... 10 V, max. 5 mA– Heating / cooling output (ao2) 0...10 V, max. 5 mA– Heating output (ao3) 3-point, AC 24 V, max. source current 0.5 A / 10 VA (optimized for actuators with a running time ofapprox. 150 s)
•   Norms und standards Protection classIII Safety extra-low voltageDegree of protectionIP 30 to EN 60529Mode of operationType 1 to EN 60730-1Software classA to EN 60730-1 EMC CE conformity to 89/336/EEC
•   Ambient conditions– Operation0...+50°C / 20...90% rH (without condensation– Transport and storage–25...+70°C / 20...90% rH (without condensation
•   Dimensions / Weight Dimensions (H x W x D) 99 x 84 x 32 mm
•   Weight 105 g
•   Housing colors Baseplate CoverNCS2005-R80B light gray(corresponds approx. to RAL 7035) RAL 9003-Signalweiss

Manufacturer Belimo