Objective/Method/Outcome
Objective: Determines if the temperature control of chiller is poor.
Method: Compares the actual temperature of the Chilled Water Supply and the setpoint and checks if it is greater than the dead band for more than the appropriate amount of time during operational hours.
Outcome: Triggers an Integrity KPI insight.
Applicable System
CWS
Description
Determine the error severity of a chilled water temperature control system in degree*hours.
This rule is part of the CopperTree Standard rule-set.
Calculate the severity metric based on the absolute difference between the water temperature and the water temperature setpoint deadband while the water temperature is outside of the deadband during scheduled hours.
Diagnosis
- Issue with control loop. Review and modify controller tuning parameters.
- Automatic setpoint control has been overridden. Revert setpoint back to automatic control.
- Input sensor(s) faulty or miscalibrated. Verify input sensor(s) operation.
Message
The chilled water supply temperature has deviated from the setpoint for more than 10 degree*hours per week while the system is enabled. Review controller tuning parameters.
Rule Template
Insight Type: Integrity KPI
Trigger Type: Active High
Default Priority
Medium
Logic
Inputs
| Input | Unit | Tags | Description |
|---|---|---|---|
| Chilled Water Supply Temperature | °C/ °F | Chilled Water Supply Temperature | The recorded water temperature |
| Chilled Water Supply Temperature Setpoint | °C/ °F | Chilled Water Supply Setpoint | The water temperature setpoint |
| Status | Chilled Water System Enabled, Chiller Status | To detect if CWS is operational | |
| Const. – Temperature Threshold | °C/ °F | To minimum temperature deviation from setpoint beyond which an insight would be generated | |
| Const. – Acceptable Weekly Threshold | °*hr | ||
| Days of operation annually | Days per year the system is operational | ||
| Cost per Degree*Hour | $ |
Notes
CTL generated:
CHWST Severity KPI
