Trane Technologies Symbio 800, Integration Manual

Page: 17 / 24

BAS-SVP046A-EN A–1
Appendix A. Arbitration
The Symbio ™ 800 controller includes arbitration logic for several points. For each read/write
point designated as “BAS”, an associated “Arbitration” point determines the behavior of that
communicated data compared to the local hardwired (or wireless) sensor and a default value.
As shown in Figure 6, p. A–1 , the arbitrator considers all possible sources of the provided data,
including Building Management Systems (BMS), local, and default. Each potential source is
defined at a pre-determined, fixed priority. When the arbitration method is selected as full/auto,
the BMS value is used instead of the local or default values.
The point designator with the arbitrator suffix includes the full priority array, allowing the user to
see the value associated with all potential sources considered in the logic. The active point
reflects the result of the arbitration logic.
Because the arbitrated points are normally associated with sensors, the default value is invalid,
meaning the value must be provided either by the BMS or the local sensor.
Figure 6. Arbitration method - full/auto
When the Arbitration Method is selected as local, the BMS value is ignored and local value is
used instead. Though the arbitration logic still considers all inputs, any values sent by the BMS
are effectively ignored.
Figure 7. Arbitration method - local