User Manual

2/6
Siemens Building Technologies Room Temperature Controller CE1N3042en
HVAC Products 22.08.2003
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.
Heating Cooling
Y
Out
[%]
XpH
w
0
100
3026D01
T [°C]
Y
Out
[%]
w
0
100
3026D02
T [°C]
XpK
Note: the diagrams only show the proportional part of the PI controller
T Room temperature
Y
Out
Manipulated variable
w Room temperature setpoint
XpH Proportional band heating
XpK Proportional band cooling
The water temperature acquired by the changeover sensor (QAH11.1 + ARG86.3) is
used by the controller to switch from heating to cooling mode, or vice versa. When the
water temperature lies above 28 °C, the controller switches to heating mode, below
16 °C it switches to cooling mode.
CM
HM
T
W
[°C]
3026D03
16 28
M
CM Cooling mode
HM Heating mode
Tw Water temperature
M Operating mode
Outputs Y1 = opening, Y2 closing and N = neutral are used to drive three-position ac-
tuators with a maximum running time of 150 seconds from the fully closed to the fully
open position.
When commissioning the controller, an opening signal of 200 seconds is delivered,
followed by a closing signal of 200 seconds to ensure the actuator will be fully closed.
When the actuator has reached the position calculated by the controller, a waiting time
of 30 seconds is observed in order to stabilize the outputs.
The control outputs carry AC 230 V.
The room temperature setpoint can be limited in increments of 1 Kelvin by making use
of the minimum and maximum limitation facility. Arbitrary setpoint readjustments can
thus be prevented.
Operating modes
The following operating modes are available:
Normal operation is activated when the external operating mode changeover switch is
not activated. In normal operation, the controller maintains the adjusted setpoint.
Energy saving mode can be activated with the external operating mode changeover
switch, provided DIP switch no. 1 is set to ON.
In energy saving mode, the setpoint of heating is 16 °C and the setpoint of cooling
28 °C, independent of the position of the setpoint knob.
Function diagram
Automatic
changeover
Three-position control
signal
Energy saver
Normal operation
Energy saving mode