For ideal performance, ensure that your system is configured with the following limitations in mind:

  • Maximum number of regular and AUX data points per Connect device: 500
  • Maximum number of COVs per Connect device: 200/minute
  • Maximum number of alarms per Connect device: 200/minute

For devices that do not support COVs, Building Operator Discovery will poll the network according to its default tuning policy. On slow networks, such as MSTP, this tuning policy may not be ideal. Refer to the Building Operator Discovery documentation for instructions to configure a custom tuning policy


AUX data points and system limits

Unlike regular data points, AUX data points do not collect historical information and are identifiable by an “aux” tag. However, AUX points are counted in the maximum number of data points per Connect device.


Building Operator Discovery supports BACnet services to discover, subscribe, read, and write the main value of BACnet analog, binary, multi state, and other object types. The following object types are available:

  • BACnet Analog Input
  • BACnet Analog Output
  • BACnet Analog Value
  • BACnet Binary Input
  • BACnet Binary Output
  • BACnet Binary Value
  • BACnet Multi state Input
  • BACnet Multi state Output
  • BACnet Multi state Value
  • BACnet Command
  • BACnet Accumulator
  • BACnet Large-Analog-Value
  • BACnet Loop
  • BACnet Positive-Integer-Value
  • BACnet Pulse Convertor
  • BACnet Averaging
  • BACnet Integer-Value
  • BACnet Load-Control


Building Operator Discovery supports Modbus function codes to read/write single Modbus coils and register.

  • Modbus FC01 Read Coils
  • Modbus FC02 Read Discrete Register
  • Modbus FC03 Holding Register
  • Modbus FC04 Input Register
  • Modbus FC05 Write Single Coil
  • Modbus FC06 Write Single Register


Building Operator Discovery supports Haystack REST API services to discover, read, and write Niagara framework-based control point objects.

  • nHaystack Boolean Point
  • nHaystack Boolean Writeable
  • nHaystack Numeric Point
  • nHaystack Numeric Writeable
  • nHaystack Enum Point
  • nHaystack Enum Writeable