Attributes (VF Primary Min Flow 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 VF Primary Min Flow Control modules:

Table 1. VF Primary Min Flow Control Attributes

Name

Type 1

Description

Default Value

Control Status

 

Current status of the module. See the PID specification for more information.

Overridden

Set Name: Control Status

Direct Acting

 

Signals the action of the PID: True= Direct Acting, False = Reverse Acting. Direct acting control is used in applications where an increase in the process variable causes the controller’s present value to increase. An example of direct acting control is temperature control with a cooling coil. With reverse acting control, an increase in the process variable causes the control present value to decrease. Three examples of reverse acting control are: temperature control with a heating coil, flow rate control, and static pressure control applications.

False

Mode

 

Desired mode of operation.

Control

Set Name: Off/Max/Control/Hold

Output Overridden

 

Not implemented at this time; for future use. Indicates whether the controlled output is overridden externally.

False

Output Position

 

Not implemented at this time; for future use. Used for bumpless transfer after an output override is released.

0.0

Percent Cmd

 

This is the analog percent output to the control device.

0.0%

PID Tuning Reset

 

Causes the PID objects to reset their tuning parameters to the default based on the appropriate Process ID.

Normal

Set Name: PID Tuning Reset

Process Dead Time

 

The time required for the process variable to begin to reflect the results of a step change of the Percent Cmd.

6 Seconds

Process Range

 

The magnitude of the range that the PID Process Variable traverses as the PID Present Value varies between its minimum and maximum values. For example, when the Process Variable ranges between 60 and 90 degrees due to the PID Present Value varying from its Low Limit to its High Limit, then Process Range is set to 30 (60 - 90).

6.3 l/s, 100 gpm

Process Time Const

 

The time required for a first-order system to reach 63% of its final magnitude given a 100% step change; it is often represented by the symbol T.

60 Seconds

Process Variable

 

When Mode is commanded to Control, this is the controlled variable. Therefore, this variable must respond to changes in the output. For example, it can be connected to the Zone Temperature.

6.3 l/s, 100 gpm

Ramp Rate

 

Analog value that defines the rate of change in Percent Cmd output.

60 per Minute

Setpoint

 

This is the desired setpoint for the process variable when commanded to Control.

6.3 l/s, 100 gpm

State

G

Indicates operating state of the module.

Control

Set Name: Off/Max/Control

OVR

1 B - BACnet Exposed Parameter, C - Configuration Mode Only, G - Default Element (Generated State, if applicable), SC - Simulation and Commissioning Modes Only, V - Calculated Value (Outputs)