Enhanced Prioritization – Equipment Runtime Analysis

Applicable Systems

  • Primary: AHU, RTU, MUA, ERV
  • Secondary: HP, FCU, UV, UH

Description / Method

Measures runtime outside occupancy to determine Potential Savings and Energy Impact. Insight is triggered when Potential Savings exceeds the predicted yearly threshold. This can be changed to trigger Energy Impact.

  • Potential Cost Savings is the energy cost based on time equipment runs unnecessarily, a forecast in $/year.
  • Energy Impact is the number of days (expressed in percent of total days analyzed) that the energy consumption has exceeded the baseline.
  • A CTL measures the cumulative sum (CUSUM) of the difference between actual energy cost and baseline energy cost – as determined by occupancy schedule.
  • A second CTL measures the cumulative sum (CUSUM) of the number of days the energy consumption has exceeded baseline.
  • A third CTL measures the cumulative sum (CUSUM) of the number of hours the equipment has run to date.

Logic

Enhanced Prioritization - Equipment Runtime Analysis
Enhanced Prioritization – Equipment Runtime Analysis
  • 1. Schedule or control outputs in manual override, at the BAS front-end or control device.
  • 2. Control program error. Verify equipment scheduling and sequence of operations.

Message

Equipment runtime issue. Please verify equipment scheduling and sequence of operations. The equipment has been running above the scheduled hours.

Notes

Default Values for Constants

  • Threshold – Potential Savings Yearly [$]:100
  • Threshold – Amperage Status [A]: 2
  • Threshold – Energy Impact Weekly [%]: 14
  • Voltage 3-phase [V] {sensor, voltage}: 480
  • Power Factor [p.f]: 0.85
  • Energy Rate [$/kWh]: 0.07

Rule Template Type

  • Insight Type: Fault Detection
  • Trigger Type: Active High

Inputs

Inputs Units Default Value Tags Description
Equipment Amps [A] {sensor, current} Amps   sensor, current Amperage of the equipment you want to monitor
Equipment Schedule {occupied}     occupied Schedule that the equipment should be running within
Threshold – Potential Savings Yearly [$] $ 100   Threshold to trigger potential savings Insight
Threshold – Amperage Status [A] Amps 2   Minimum current level that will be considered to be on
Threshold – Energy Impact Weekly [%] % 14   Weekly Energy Impact
Voltage 3-phase [V] {sensor, voltage} Voltage 480 sensor, voltage 3-Phase Line-to-Line Voltage
Power Factor [p.f]   0.85   Power Factor of equipment
Energy Rate [$/kWh] $/kWh 0.07   Local utility rate

Output Calculated Trend Logs

Output CTL Units Description
EquipmentRuntime_HoursCUSUM Hours Cumulative sum of equipment runtime in hours
PotentialSavingsCUSUM[$] $ Cumulative sum of potential cost savings
PotentialSavings_Yearly[$] $ Potential Savings if runtime issues are resolved
DaysAboveBaselineCountCUSUM Days Cumulative Sum of days equipment is running above the baseline count
EnergyImpact % Energy Impact of Equipment running out of schedule