blockTimeSuppression
Calculate a time-delay period after change in set point
Information
This sequence checks if there is setpoint change and if the time-based suppression has finished. The implementation is according to the Section 5.1.20 of ASHRAE Guideline 36, May 2020.
Calculate a time-delay period after any change in setpoint based on the difference between the controlled variable at the time of the change and the new setpoint. The default time delay period shall be as follows:
-
For thermal zone temperature alarms: 18 minutes per °C (10 minutes per °F)
of difference (
chaRat) but no longer than 120 minutes (1800). -
For thermal zone temperature cooling requests: 9 minutes per °C (5 minutes per °F)
of difference (
chaRat) but no longer than 30 minutes (1800). -
For thermal zone temperature heating requests: 9 minutes per °C (5 minutes per °F)
of difference (
chaRat) but no longer than 30 minutes (1800).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Real | chaRat | 540 | Gain factor to calculate suppression time based on the change of the setpoint, seconds per Kelvin. For cooling or heating request, it should be 540 seconds, for temperature alarms, it should be 1080 seconds |
| Real | maxTim | 1800 | Maximum suppression time. For cooling or heating request, it should be 1800 seconds, for temperature alarms, it should be 7200 seconds |
| Advanced | |||
| Real | samplePeriod | 120 | Sample period of component, set to the same value as the trim and respond that process static pressure reset |
| Real | dTHys | 0.25 | Near zero temperature difference, below which the difference will be seen as zero |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | TSet | Setpoint temperature | |
| Buildings.Controls.OBC.CDL.Interfaces.RealInput | TZon | Zone temperature | |
| Buildings.Controls.OBC.CDL.Interfaces.BooleanOutput | yAftSup | True when there is no setpoint change, or suppression time has passed after setpoint change |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Buildings.Controls.OBC.CDL.Reals.Min | supTim | Calculated suppression time due to the setpoint change |
Revisions
-
June 18, 2024, by Antoine Gautier:
Replacedholdwithpreto break the algebraic loop involving the latch component. This is for issue 3883. -
December 12, 2023, by Jianjun Hu:
Reimplemented the check of ignoring the first sampling period. This is for issue 3596. -
August 1, 2020, by Jianjun Hu:
First implementation.