Changeover bypass - Johnson Controls - LIT-12011950 - Building automation software - Smart Equipment Controller - 5.0

Smart Equipment Controls Sequence of Operation Technical Bulletin

Product
Building Automation Systems > Building Automation Systems > Smart Equipment Controller
Document type
Technical Bulletin
Document number
LIT-12011950
Version
5.0
Revision date
2024-06-06
Product status
Active

Setpoints and related data

The setpoints and related data include the following items:

  • Rooftop Controller Type (CntrlType) Changeover Bypass
  • VZC Online
  • COBP Mode
  • COBP Supply Air Temperature Setpoint (COBP SAT SP)

Operation

The VZC sets a point called VZC Online on the SSE controller to Yes to indicate that a Verasys system is connected.

The VZC sends the COBP Mode it wants the SSE controller to operate in (Heat/Cool/Fan Only/Balancing/Satisfied/Off) and the COBP Supply Air Temperature Setpoint.

Cooling: COBP Mode = Cool and Supply Air Temperature > COBP Supply Air Temperature Setpoint, Compressors are staged on.

Heating: COBP Mode = Heat and Supply Air Temperature < COBP Supply Air Temperature Setpoint, Heating is staged on.

Note: The COBP Supply Air Temperature Setpoint needs to be an appropriate value for the current COBP Mode or else stages may not turn on as expected. For example, if COBP SAT SP is set to 110°F but the COBP Mode is set to Cool, no compressors will turn on assuming the SAT is below 110°F.

The same sequences described above apply when the unit is in Unoccupied mode.