Siemens RDG400 manual Functions, Temperature control, General note, Described in section, Display

4 Functions

4.1Temperature control

General note	Setting of the control parameters (P01 etc., mentioned throughout the document) is
	described in section 4.12.

The thermostat acquires the room temperature via built-in sensor, external room temperature sensor (QAA32), or external return air temperature sensor (QAH11.1), and maintains the setpoint by issuing actuator control commands to heating and/or cooling equipment. The following control outputs are available:

•Modulating PI / P control with DC 0 … 10 V control output

•Modulating PI / P control with 3-position control output

•Modulating PI / P control with PWM output

•On/off control (2-position)

	The switching differential or proportional band is 2 K for heating and 1 K for cooling
	(adjustable via parameters P30 and P31).
	The integral action time for continuous PI control is 5 minutes (adjustable via
	parameter P35).
Display	The display shows the acquired room temperature or the Comfort setpoint, selecta-
	ble via parameter P06. The factory setting displays the current room temperature.
	Use parameter P04 to display the room temperature or setpoint in °F rather than
	°C as needed.
/	If the thermostat is used in a system with manual heating/cooling changeover
	(P01=2), the heating and cooling	symbols on the display show the terminal
	unit status. Thus, the symbols are displayed even when the thermostat operates in
	the neutral zone. For all other cases, the heating and cooling		symbols are
	displayed when the heating or cooling output is energized.
Concurrent display of	Concurrent display of the current temperature or setpoint in °C and in °F
°C and °F	(parameter P07) is possible.

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Siemens	RDG100…/RDG110…/RDG140.../RDG160… Basic Documentation	CE1P3182en
Building Technologies	Functions	28 May 2009