Attributes (Cooling Tower Control) - Johnson Controls - Metasys - LIT-12011147 - Software Application - Controller Configuration Tool - 16.0

Controller Tool Help

Brand
Johnson Controls
Metasys
Product name
Controller Configuration Tool
Document type
User Guide
Document number
LIT-12011147
Version
16.0
Revision date
2023-10-02
Language
English

The following table describes the attributes used by the Cooling Tower Control modules.

Table 1. Cooling Tower Control Attributes

Name

Description

Default Value

Blocking Protect

This input causes the fan to run when the input value is Protect, Tower Enable is True, and System Enable is True. When this input is Protect and the system and tower are enabled, the fan runs for 5 seconds (default) once a week (default)

Off

Set Name: Blocking Protect

Device OnOff

Indicates the desired fan operation. This output is typically connected to either a constant speed fan or a variable speed fan. This output is also used for runtime totalization for this tower.

Off

Set Name: Off/On

Fan Type

This input indicates the tower configuration. The tower may be VFD, one speed fan, two speed fans, three speed fans, or vernier fan (a single fan with one or more one speed fans).

VFD

Set Name: Tower Fan Type

Instant Shutdown

This input provides a means to shut the tower down quickly. When true, the output’s Device OnOff, Speed 1 OnOff, Speed 2 OnOff and Speed 3 OnOff are set to Off. The Iso Valve Open Close output is set to Close.

False

Interstage Delay

This input is the minimum time between switching speeds.

120 Seconds

Display Precision: 1s

Iso Valve Cmd

This input is the cooling tower isolation valve command.

False

Iso Valve OpenClose

This output drives the isolation valve BO.

Close

Set Name: Close/Open

Iso Valve Setup

This input provides the cooling tower isolation valve setup. When set to Auto, the Iso Valve OpenClose output reflects the Iso Valve Cmd. When Set to On, the Iso Valve OpenClose output is always Open.

Auto

Set Name: Fan Mode Seq 4

Percent Cmd

This indicates the desired speed of a variable speed fan.

%

Pid Pct Cmd

This is the input from the Cooling Tower PID Control module. This input is the signal passed through for variable speed fans.

0.0%

Speed 1 Cmd

Input from the sequencer indicating that the tower should operate in speed 1.

False

Speed 2 Cmd

Input from the sequencer indicating that the tower should operate in speed 2.

False

Speed 3 Cmd

Input from the sequencer indicating that the tower should operate in speed 3.

False

Speed 1 OnOff

This is the desired fan speed 1 operation. This output is typically connected to a multi-speed fan’s low speed or speed 1 contactor.

Off

Set Name: Off/On

Speed 2 OnOff

This is the desired fan speed 2 operation. This output is typically connected to a multi-speed fan’s low speed or speed 2 contactor.

Off

Set Name: Off/On

Speed 3 OnOff

This is the desired fan speed 3 operation. This output is typically connected to a multi-speed fan’s low speed or speed 3 contactor.

Off

Set Name: Off/On

State

The current state of this output controller.

Off

Set Name: Fan Speed

See Primary States (Cooling Tower Control).

System Enable

This input indicates when the chilled water system is enabled.

True

Tower Enable

This input indicates when this tower is enabled. When the tower is enabled, any isolation valve associated with this tower is open.

True