Black Box BRI-HUB ISU2011-4-UK Manual De Usuario

 

 
 
The TE-ports termination resistors are permanently active and cannot be switched off.  
 
Please install terminating resistors to the end of the connecting cables.  
 
 

 

 
 
 
In the above example the Term-switch must be in the off position, i.e. termination resistors 
are off.  This is because the BRI-Hub is not connected to the end of the bus. 
 
 

If the BRI-Hub loses power, the terminal devices directly connected to the NT ports will still 
operate. For this to happen case one must observe the maximum cable length and the position 
of the terminating resistors. In more detail this is: 
 

•

  The length of the cable connecting the NT to the BRI-Hub plus the length of the cable 

connecting the BRI-Hub to the TE on the second NT port must not be longer than 150m. 
Both cables form a passive bus. 

 

•

  In case of a bus installation at the NT port, BRI-Hub must be the last device on the bus. 

 

•

  The termination resistors must be switched off. Termination resistors must be installed at 

the end of the TE’s bus