Wiring an STR-150 into a Xenta 121

Issue

The STR-150 Installation Instructions state that the stat wires into D1, X1, and M of the Xenta 100 series controller. However, this is not applicable to the Xenta 121, which does not have a D1 input.

Product Line

TAC Vista

Environment

  • Xenta 121
  • STR-150

Cause

The correct terminal for the mode input from the STR-121 is labeled differently on the Xenta 121 versus all other Xenta 100 series controllers.

Resolution

Wire the stat as follows:

STR-150 Xenta 121
Label Terminal Label Terminal
Mode 11 Y1 5
Data 12 X1 7
M 13 M 6

 

The Purpose of output Y1

The only function that the STR-150 uses Y1 for is to get an effective occupancy signal from the Xenta 121. When the Xenta 121 is occupied, the man symbol will be displayed on the STR-150. If Y1 is already in use then the Status LED can be moved to a K output as explained in Lessons Learned Article #8262. In order to activate this feature, the Hardwired status LED option must be selected. This can be found under the Configuration tab > Connected devices > Room unit in ZBuilder.

If this feature is not desired then unselect Hardwired status LED and only wire up X1 and M. The STR-150 will still be able to send the controller the temperature, setpoint, bypass signal, and fan speed.