Technical data

1. When the thermostat is powered up, a closing command for the actuator
running time + 150% is provided to ensure that the actuator fully closes and
synchronizes to the control algorithm.
2. When the thermostat calculates the positions "fully close" or "fully open", the
actuator's running time is extended + 150% to ensure the right actuator
position is synchronized to the control algorithm.
3. After the actuator reaches the position calculated by the thermostat, a waiting
time of 30 seconds is applied to stabilize the outputs.
The demand calculated by PI control from the current room temperature and set-
point is provided via Y1 and Y3 to the valve actuator as a PWM (pulse width
modulation) signal for thermal actuators. The output is activated for a period
proportional to the heating / cooling demand and then switched off for the rest of
the PWM interval.
The interval is 150 seconds (factory setting). It can be adjusted via parameters
P44 (Y1) or P45 (Y3). These parameters are only visible if 2-position is selected via
DIP switches 4 and 5 and if PWM is selected via P46 and P47.
For PWM, the integral time (P35) must be set to 0.
For thermal valve actuators, set the running time to 240 seconds.
• Never apply PWM to a motorized actuator
• It is not possible to ensure exact parallel running of 2 or more thermal valve
actuators. If several fan coil systems are controlled by the same room
thermostat, preference should be given to motorized actuators with on / off or
3-position control
For electric heaters, set the running time to 90 seconds.
To avoid burn-off of mechanical contacts by frequent switching, use a current valve
in place of a relay or contactor.
For PWM, the integral time (P35) must be set to 0.
This function is available with RDG160KN only.
The demand calculated by PI control from the current room temperature and
setpoint is provided via Y10 and Y20 to the valve actuator as a continuous
DC 0...10 V signal.
• The demand calculated by PI control from the current room temperature and
setpoint is provided via Y20 as a continuous DC 0...10 V signal.
• The signal converter (SEM61.4) converts the DC 0...10 V signal to AC 24 V
PDM pulses for the current valve.
• The current valve (SEA45.1) supplies the electric heater with pulsed current.
On RDG160KN the electrical heater can be controlled via the On/Off output (Q2)
by setting P47 = 1. Adaptive temperature compensation: see 3.6.4.
Synchronization
PWM control
(RDG100KN only)
Note!
PWM for therm
al
valve actuators
Note!
PWM for electric heaters
Note!
DC 0...10 V control
DC 0...10 V
for valve actuators
DC 0...10 V
for electric heaters
Note!
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Siemens RDG100KN, RDG160KN Basic documentation CE1P3191en
Building Technologies Functions 2014-05-23