Overview of control outputs
Different control output signals are available. They need to be defined during commissioning (see below).
Control output → Product no.↓ |
2-position |
3-position |
|---|---|---|
| RDF302, RDF302/VB, RDF302.B | Y11, Y21 (2 x SPST) |
Y11, Y21 *) (1 x  /  ) |
*) Only on 2-pipe application
ON/OFF control signal (2-position)
The valve or compressor receives the OPEN/ON command via control output Y11 or Y21 when…
the acquired room temperature is below the setpoint (heating mode) or above the setpoint (cooling mode).
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…
the acquired room temperature is above the setpoint (heating mode) or below the setpoint (cooling mode).
the valve has been active for more than the “Minimum output on-time” (factory setting 1 minute, adjustable via parameter P49).
Electric heater control signal
(2-position)
The electric heater receives an ON command via the auxiliary heating control output (Y…, see Mounting Instructions) when…
the acquired room temperature is below the “Setpoint for electric heater”
the electric heater has been switched off for at least 1 minute
The OFF command for the electric heater is output when…
the acquired room temperature is above the setpoint (electric heater)
the electric heater has been switched on for at least 1 minute
Caution 
A safety limit thermostat (to prevent over-temperatures) must be provided externally.
Adaptive temperature compensation for electric heater
When an electric heater is connected directly to the ON/OFF Y21, the current
causes the relay contact to heat up. This falsifies the reading of the internal
temperature sensor. The thermostat compensates the temperature if the rated
current/power of the electric heating is entered in the parameters
P46 (load current electric heater): factory setting: 0 A, setting range: 0.0…5.0 A.
3-position
control signal
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.
Synchronization
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.
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.
After the actuator reaches the position calculated by the thermostat, a waiting time of 30 seconds is applied to stabilize the outputs.