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Siemens  TX-I/O™ Module system – Functions and operation  CM110561en_08 
Building Technologies  Digital output functions  2018-10-25 
Parameter  Description  Range  (default) 
Direction  Exchange of outputs (only n and n+1) to correct faulty 
wiring.  
 
Direction = False 
(normal) 
Direction = True 
(inverted) 
BOOL  (False) 
True / false 
 
•  If EndPosDetection = inactive, the runtimes RunTimeUpDown and 
RunTimeDownUp must be parameterized.  
•  If EndPosDetection = active, the motor current at the relay feeds is measured. This 
allows for detecting the end positions and determine the motor runtimes between 
positions Up and Down2. The runtime measurement RunTimeUpDown and 
RunTimeDownUp is executed each time when the blinds drives the entire stretch 
from Up to Down2 or vice-versa.  
Values RunTimeUpDown and RunTimeDownUp are saved to the module's flash 
memory. They change over time (temperature deviations, aging).  
Changes to the motor runtime are sent to the bus master for subsequent evaluation 
in the application function. 
Changes > 7% or > 3 s are saved to flash memory. 
Changes > 15% are not saved as unbelievable. 
•  If EndPosDetection = once, the motor current measurement is active, the stroke 
model is synchronized in the end positions, but the run times are only saved to the 
flash memory once after start-up. 
•  Command CAL can be used to force runtime measurement. 
If EndPosDetection = Inactive, the module ignores the command. 
 
•  Because of the current measurement, interposing relays for the control of several 
blinds in parallel are not admitted. 
 
If process value (AOBValue) changes, the new value overwrites the old value.  
The function drives to the new position in case of absolute commands. 
 
•  The I/O status LEDs are lit when the associated relay is active  
•  In case of an error, the I/O status LED and the module status LED are lit. 
 
Details, blinking pattern and errors in particular: See section "Display, operation and 
diagnosis" in [6] "TX-I/O™ engineering and installation".  
 
•  The relays drop off in case of a DC 24 V bus supply failure.  
When power is restored, the relays remain inactive until a valid process value is 
available. 
•  In case of bus failure: 
The behavior can be parameterized for each I/O function:: BackupMode, 
BackupValue and BackupDelay; see above parameters. 
 
Reaction to changes of 
AOBValue 
Response in case of error