User Manual

ManualsBrandsSiemens ManualsRoom controlsUniversal Room Controller

CE1N3042en

22.08.2003

Siemens Building Technologies

HVAC Products

042

RCU20

Room Temperature Controller

RCU20

for heating or cooling systems

Modulating PI control

Three-position output for heating or cooling

Operating modes: normal operation, energy saving or OFF

Automatic heating / cooling changeover

Operating mode changeover input for remote control

Operating voltage AC 230 V

Use

Control of the room temperature in individual rooms of ventilation or air conditioning

plants that are heated or cooled.

For the control of the following pieces of equipment:

• Three-position valve actuators

• Three-position air damper actuators

Summary of content (6 pages)

PAGE 1
3 042 RCU20 Room Temperature Controller RCU20 for heating or cooling systems Modulating PI control Three-position output for heating or cooling Operating modes: normal operation, energy saving or OFF Automatic heating / cooling changeover Operating mode changeover input for remote control Operating voltage AC 230 V Use Control of the room temperature in individual rooms of ventilation or air conditioning plants that are heated or cooled.
PAGE 2
Functions The controller acquires the room temperature with its integrated sensor and maintains the setpoint by delivering three-position control commands to the valve. The controller provides PI control. The proportional band in heating mode is 4 Kelvin and in cooling mode 2 Kelvin. The integration time is 5 minutes.
PAGE 3
Operating mode changeover switch A changeover switch can be connected to status input D1-GND. When the switch closes its contact (caused by an open window, for instance), the operating mode will change from normal operation to energy saving mode (provided DIP switch no. 1 is set to ON), or from normal operation to OFF (provided DIP switch no. 1 is set to OFF). Ordering When ordering, please give name and type reference. The QAH11.
PAGE 4
Accessories Description Adapter plate 120 x 120 mm for 4“ x 4“ conduit boxes Adapter plate 96 x 120 mm for 2“ x 4“ conduit boxes Adapter plate for surface wiring 112x130 mm Type reference ARG70 ARG70.1 ARG70.2 Notes In systems without automatic changeover, the temperature sensor can be replaced by an external switch for manual changeover. In systems with continuous heating operation, no sensor will be connected to the controller’s input.
PAGE 5
Technical data Power supply Functional data Environmental conditions Norms and standards Operating voltage Frequency Power consumption P-band XP Setpoint setting range Setpoint «Energy saving mode Setpoint «Energy saving mode Integration time Control outputs Y1, Y2 Voltage Current Changeover - status input B2 », heating », cooling Status input D1 and GND Contact sensing Insulation against mains Operating action Perm. cable length with copper cable 1.
PAGE 6
L M D1 GND B2 Y1 N N Y2 3042G01 Connection terminals L N B2 D1 Operating voltage AC 230 V System neutral Signal input “Changeover sensor“ Signal input for potential-free operating mode changeover switch (selectable operating action) Control output “Open valve“, AC 230 V Control output “Close valve“, AC 230 V SELV Y1 Y2 Connection diagram N1 S1 L S1 B2 L M N Y1 Y2 N1 3042A01 N B2 Y1 D1 GND B2 Y1 N Room temperature controller External operating mode changover switch (N.O.