Siemens RDB160BN - Control Outputs; Available Control Output Signals; Specific Output Controls; Valve Exercising Feature

Control outputs
Control sequences
5
20
| 52 A6V11917618_en--_b
5 Control outputs
Different control output signals are available; they are defined during
commissioning (see below).
Product no. /
Control output
2-position (PWN
or On/Off)
DC 0…10 V
3-position
RDB160BN
DO4, DO5
(2x Triac)
AO1, AO2
1)
DO4, DO5
2)
(1x / )
1)
AO2 is shared with DC 0…10 V fan and can be used for valve actuators only
with 1-, 2- or 3-speed fan application.
2)
Only available for 2-pipe applications
On/Off and PWM control signal (2-position)
If the measured room temperature is below the setpoint (heating mode) or
above the setpoint (cooling mode), the valve receives the 'Open' or 'On'
command via control output DO4 or DO5. The valve receives the 'Off' command
if the measured room temperature is above the setpoint (heating mode) or
below the setpoint (cooling mode).
The control hysteresis of On/Off control output can be set via parameter P10.
The factory setting is 1 K.
The pulse degree of the PWM output can be set for heating (DO4) and cooling
(DO5) valve independently via parameters P18 and P19. The factory setting is
60 seconds.
Electric heater control signal (2-position)
The electric heater receives the 'On' command via the DO5 output with On/Off
logic only if the measured room temperature is below the setpoint for the
electric heater.
It receives the 'Off' command if the measured room temperature is above the
setpoint for electric heater.
CAUTION
Overtemperature
To avoid overtemperature, a safety limit thermostat must be provided
externally.
3-position control signal
Output AO4 provides the 'Open' command, and AO5 the 'Close' command to the
3-position actuator.
The factory setting for the actuator's running time is 120 seconds. It can be
defined via parameter P20.
Valve exercising feature
The valves are operated from time to time to prevent them from seizing after
long periods of inactivity. For example, in winter, only heating valves are used
and thus, cooling valves must also be operated from time to time so that they
do not get stuck in one position.
The time between two exercises is set via parameter P22 for the heating
actuator and P23 for the cooling actuator. The default setting is 23 hours.