Primary States (Preheat Proportional Valve with Return Water Control) - 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
  • Off: Turn everything off. The Heating Percent Cmd is set to 0%.

  • Max: Open the heating valve. The Heating Percent Cmd is set to 100%.

  • Hold: Hold the outputs at their current position. If the Output Overridden input is true, then the Output Position input is passed to the Heating Percent Cmd.

  • Water Flush: Open the valve to the Water Flush Position.

  • Limited Max: Open the valve to the Limited Max Value. This state may be used for unoccupied heating.

  • T Control: Open the heating valve and adjust the output to control the Process Variable. The module controls the output in order to maintain the Process Variable at the Setpoint. The Heating Percent Cmd adjusts between 0% and 100%.

  • LL-T Control: Open the heating valve and adjust the output to control the Limit Variable. The module controls the output to maintain the Limit Variable at the Limit Setpoint. The Heating Percent Cmd adjusts between 0% and 100%.

  • Low OA Temperature: Open the valve to the Low OA Temperature when the Protect-T is less than Protect-Tsp.

  • Failsoft: Open the valve to the Failsoft Value. This state may be used when the control temperature is unreliable.

  • Low OA Temperature Startup: This mode activates the T Control state section, but limits the rate at which the valve can close so that the unit can safely come into control (typically used for 100% OA units with low OA temperatures at startup).

  • Remain In Control: Modulate the valve to control the Limit Variable to the Limit Setpoint. If the Limit Variable is reliable, the module controls the output to maintain the Limit Variable at the Limit Setpoint. Use this mode only as a shutdown strategy to add energy to the duct when the fan is off. Do not use this mode for general temperature control.

Table 1. Preheat Proportional Valve with Return Water Control Command Hierarchy

OA Temperature isReliable

Low Limit Process Variable isReliable

LowOAT

PID Tuning Reset

Mode

State

*

*

*

*

Off

Off

*

*

*

*

Max

Max

*

*

*

*

T Control

T Control

*

*

*

*

LL-T Control

LL-T Control

*

*

*

Reset 1st PID

Hold

T Control

*

*

*

Reset 2nd PID

Hold

LL-T Control

*

*

*

*

Hold

Hold

TRUE

*

TRUE

*

Low OA Temperature

LL-T Control

TRUE

*

FALSE

*

Low OA Temperature

Off

FALSE

*

*

*

Low OA Temperature

Failsoft

*

*

*

*

Water Flush

Water Flush

*

*

*

*

Limited Max

Limited Max

*

*

*

*

Failsoft

Failsoft

*

*

*

*

Low OA Temperature Startup

T Control

*

*

*

*

Remain in Control

Remain in Control

*

*

*

*

Remain in Control

Failsoft