Xenta 102-AX Setpoint Offset Value will not Hold

Issue

The nviStPointOffset in the Xenta 102-AX controller will not hold a value when it is entered in Vista Workstation or through the browser in LonMaker/NL220.

Product Line

TAC Vista

Environment

  • NL220
  • LonMaker
  • Vista Workstation
  • Xenta 102-AX Plug-in

Cause

There are two possible reasons for this issue:

  1. If there is a SNVT bound to nviStPointOffset, then the value that is manually entered will be pushed out every time the SNVT value is sent across.

  2. The Stat Adjustment Range in the Xenta 102-AX plug-in may be set to low causing the value too not hold.

Resolution

  1. First check in LonMaker/NL220 if there is a SNVT bound to nviStPointOffset. If there is a binding here then it will either need to be broken or the point will not be able to be overridden. If there is no binding then move on to step two.
  2. Open up the Xenta 102-AX plug-in and click on the Operating Parameters tab. Check what value is set in the Stat Adjustment Range field.

This value needs to be set high enough to accommodate the setpoint offset range that is desired. In order to enter a positive or negative offset of 5°F, then a value of 5 needs to be entered into the Stat Adjustment Range. If the value is set to 5°F and an offset of 6°F is entered, the entered value will revert back to the maximum amount allowed by the range, 5°F.

Note: Keep in mind that this setting is also used to set up the range for wall stats that have an adjustment feature. In this case the range is divided by two to give the wall stat the capability to go negative and positive. For example if 5°F were entered into this setting, the wall stat will only be able to adjust up and down 2.5°F unlike nviStPointOffset that will be able to move up and down 5°F.