Three-Position Control Signal (Bo 3-Pos Relay, Bo-3-Pos Triac / Y250T)) - Siemens TX-I/O TXM1.8D Functions And Operation

Application
Hardware
Function
Configurable / fixed
variables
Parameter details
Runtime
Pause
Reaction Time
(Series D and higher)
42/54
Siemens
Building Technologies
5.9 Three-position control signal
(BO 3-Pos Relay, BO-3-Pos Triac / Y250T))
For open/close control of three-position actuators without feedback (position
potentiometer), e.g. for
– Valve actuators
– Damper actuators
– Third-party actuators
The function uses two I/O points which must be on the same module and adjacent to
each other. I/O point (n) = Open, I/O point (n + 1) = Close.
• The function converts the process value into 3-position positioning signals.
An internal stroke algorithm calculates the required length of the OPEN or CLOSE
pulses from the actuator runtime and the position specified in the process value.
No position feedback is required from the actuator.
• The function supports asymmetrical actuators with different opening and closing
runtimes. However, this function can only be used if it is also supported by the bus
master.
Value
Rise Time
Fall Time
Break time
Reaction Time
(Series D and higher)
Nz
Hys
Backup mode
Backup Value
Synchronization
Direction
(Series D and higher)
Asymmetric runtimes can be set as parameters (if supported by the bus master).
Delay time before the actuator changes direction
Additional runtime when traveling to or from 0 % (clearance between motor and drive).
Note: Reaction Time is not part of the stroke model.
TX-I/O™ Module system – Functions and operation
Digital output functions
Description
Time to OPEN
Time to CLOSE
Pause between opening
and closing
Additional runtime when
traveling to or from 0 %
Dead band
Hysteresis
Response of process value
in the event of bus failure
Backup value if
Backup Mode = Value
Synchronization mode
Inversion of the outputs to
fix incorrect wiring
Value range (Default)
6.3 ... 6553.5 s (150.0 s)
6.3 ... 6553.5 s (150.0 s)
0...25.5 s (0.1 s)
0...50.0 s (0.0 s)
0...10%
0...10%
Keep = Last active value
No = 0%
Value = Backup Value
0.01...100%
Details see below
False (normal) (False)
True (inverted)
CM110561en_08
2018-10-25
(1 %)
(2 %)
(No)
(0 %)