8 control outputs, 1 control output for air flow, Single duct with radiator or floor heating – Siemens RDG400 User Manual

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Siemens

RDG100, RDG100T, RDG110, RDG140, RDG160 Basic Documentation

CE1P3182en

Building Technologies

Functions

28 May 2009

4.8

Control outputs


Different control output signals are available depending on the configuration of
thermostat via DIP switches 4 & 5, and parameters P46 & P47.

Control output


Product No.

Modulating
DC 0 … 10 V

2-position
on/off

2-position
PWM

Modulating
3-position

RDG400

Y10

Y1

Y1

Y1/Y2
(1 x / )



4.8.1 Control output for air flow


The demand calculated by the PI control from the current room temperature and
setpoint is provided to the valve actuator as a continuous DC 0...10 V signal via
output Y10.

A 3-position control output for a damper has 2 control signals, one for the “opening”
command and one for the “closing” command. The thermostat has an internal
stroke model to calculate the position of the actuator. Therefore the running time
from the fully closed to the fully open position has to be adjusted via parameter P44
(from 20…300sec; factory setting is 150 seconds).

In single-duct applications, a closing synchronization is done to readjust the
internal stroke model to the real position of the actuator.
1.

When the controller starts up, a closing signal (actuator running time + 150%
= 2.5 x running time) is delivered to ensure the actuator will be fully closed
and synchronized with the control algorithm.

2.

Each time the controller calculates the position fully closed, the actuator’s
running time is extended + 150% to ensure the right position of the actuator.

3.

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.


Note: opening synchronization is available for valve outputs only.

Overview of control
outputs

DC 0..10 V
control signal

3-posotion
control signal

Synchronization

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