How Does Virtual Energy Metering Work? – Delta Controls

Note: Virtual energy metering is supported in firmware 2.4 or later and enteliWEB 4.23 or later.

Due to the addition of the ATZ and BTZ objects, databases created in 2.4 are not compatible with devices running older firmware.

What is Virtual Metering?

Virtual metering allows the O3 to provide insight into energy usage of equipment it controls or is integrated to. Using virtual metering, you can save money on estimating energy usage without the cost of a real power meter and associated installation costs.

Setting up Virtual Metering

There are a few key components to setting up virtual energy metering:

Step 1: Create and configure the ATZ object

Create the ATZ (Analog Totalizer) object, which calculates consumption and peak demand.
Ensure you have entered the following required parameters for each object, where required.
- ATZ:
  - Input Reference: Input Reference specifies the object that provides the measured value that you want the ATZ object to totalize. By default, the ATZ object totalizes the input reference object's present value.
  - Consumption Units: Consumption Units specifies the units that are displayed in the value bar and with other consumption values.
  - Conversion Rate: The Conversion Rate setting specifies the rate of change used by the Input Reference.
  - Occupancy Reference (Optional): Occupancy Reference specifies the object that provides occupancy status.

For more information about configuring ATZ objects, see the ATZ topics in the online help.

Step 2: Determine Virtual Demand

Calculate the virtual demand for your space using GCL+.

The following is an example of a GCL formula used to calculate the virtual demand:

Scenario for this formula: Pair of lighting AOs are both set to 50%

Variable MaxPower As Real
//Set max power to 0.140 kW
MaxPower = 0.140

//Set AV to equal current demand power
'Lighting Virtual Power Demand' = (('Light 1 Control Output' * 0.01) + ('Light 2 Control Output' * 0.01)) * MaxPower

Step 3: Set the Virtual Demand

Set the virtual demand to an accumulated value (AV).

Step 4: Enter the AV into the Input Reference field

Enter the accumulated value into the input reference field, and the ATZ will immediately begin totalizing.

Note: You can use eVAULT and enteliWEB/enteliCLOUD for trending, archiving, and reporting.

See the following example of an ATZ object configured in enteliWEB:

ATZ