Primary States (Min OA Fan Constant Capacity) - 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
  • No Flow: This mode closes the OAD, and it de-energizes the minimum injection fan.

  • Max Flow: This mode opens the OAD, and it energizes the minimum injection fan.

  • Start: This mode opens the OAD, and the minimum injection fan is off. This mode is used to sequence the damper and the fan to ensure the damper is opening before the fan is energized.

Table 1. Min OA Fan Constant Capacity Command Hierarchy

Mode

Min Flow Control Enable

Damper Ready

State

Emergency Flow

*

TRUE

Max Flow

FALSE

Start

No Flow

*

*

No Flow

Max Flow

TRUE

TRUE

Max Flow

FALSE

Start

FALSE

*

No Flow

The Min Flow Control Enable Input indicates that the damper may be opened, and the fan may be energized. This input is True when the Low Limit Process variable is reliable, and it is more than the Low Limit Setpoint.

The Damper Ready input indicates that the damper has started to open, the damper delay has expired, and the fan is now allowed to start.