Siemens RDF302 - Control Outputs; Overview

30 / 58
Siemens RDF302 Basic documentation CE1P3079en
Building Technologies 07 Dec 2011
3.7 Control outputs
3.7.1 Overview
Different control output signals are available. They need to be defined during
commissioning (see below).
Control output
Product no.
2-position 3-position
RDF302 Y11, Y21
(2 x SPST)
Y11, Y21 *)
(1 x
/ )
*) Only on 2-pipe application
The valve or compressor receives the OPEN/ON command via control output Y11
or Y21 when…
1. the acquired room temperature is below the setpoint (heating mode) or above
the setpoint (cooling mode).
2. the control outputs have been inactive for more than the “Minimum output
OFF-time” (factory setting 1 minute, adjustable via parameter P48).
OFF command when…
1. the acquired room temperature is above the setpoint (heating mode) or below
the setpoint (cooling mode).
2. the valve has been active for more than the “Minimum output on-time” (factory
setting 1 minute, adjustable via parameter P49).
The electric heater receives an ON command via the auxiliary heating control
output (Y…, see Mounting Instructions) when…
1. the acquired room temperature is below the “Setpoint for electric heater”
2. the electric heater has been switched off for at least 1 minute
The OFF command for the electric heater is output when…
1. the acquired room temperature is above the setpoint (electric heater)
2. the electric heater has been switched on for at least 1 minute
A safety limit thermostat (to prevent over-temperatures) must be provided
externally.
Output Y11 provides the OPEN command, and Y21 the CLOSE command to the 3-
position actuator.
The factory setting for the actuator's running time is 150 seconds. It can be
adjusted via parameter P44.
The parameter is only visible if 3-position is selected via DIP switches.
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.
Overview of control
outputs
ON/OFF control signal
(2-position)
Electric heater control
signal
(2-position)
Caution
3-position
control signal
Synchronization