Economizer Damper (Common MAD Output) (MADD-MZ) - Johnson Controls - Metasys - LIT-12011147 - Software Application - Controller Configuration Tool - 15.0

Controller Tool Help

Brand
Johnson Controls
Metasys
Product name
Controller Configuration Tool
Document type
User Guide
Document number
LIT-12011147
Version
15.0
Revision date
2022-11-18
Language
English

The selection options for Economizer Damper(s) are:

  • Economizer Damper (Common MAD Output)

  • Economizer Suitability

    • Network Command

    • Enthalpy Switch (BI)

    • Outdoor Air

      • Dry Bulb Temp Economizer

      • Temp & Enthalpy Economizer

      • Outdoor Air versus Return Air: This option compares outdoor air with return air to switch the economizer.

  • Mixed Air Damper Minimum Position Reset by CO2 Sensor

  • Reduce Outdoor Air on Low Temperature

  • Damper Minimum Position Reset by OA Flow

    • Velocity Pressure (Pitot Tube)

    • Flow Measurement (Scaled)

The Reduce Outdoor Air on Low Temperature selection enables logic that reduces the intake of outdoor air when the Mixed Air Temperature is low. This reduction is accomplished by modulating closed the outdoor dampers.

If a preheat coil is located downstream of the mixing plenum (that is, it is in the mixed air), the Preheat Temperature (downstream of the coil) serves as the process variable for this control strategy. Otherwise, the Mixed Air Temperature serves as the process variable.

The control logic for the low limit strategy is embedded directly into the Output Control modules and activated simply by connecting the appropriate setpoint and process variable. The logic takes precedence over all logic other than Emergency Modes.