About Measuring Components

Measuring components are single points for which data will be received and stored in the system.

A measuring component can be associated to a device, which can have one or more measuring components, or it can be "virtual" or "stand-alone," meaning that it is not associated to a device.

The base package supports the following types of measuring components:

Physical : Physical measuring components are those that physically exist, and that are linked to a device that can be configured differently over time. Interval channels and scalar registers are examples of physical measuring components.
Note: The terms register and channel are synonyms for measuring component.
Standalone: A standalone measuring component is used to record measurements for something that does not have a physical presence or is not associated to a particular device or service point. For example, you might create a standalone measuring component to record the average daily temperature supplied by a weather station. Standalone measuring components can be identified through Standalone Identifier.
Scratchpad: Users create scratchpad measuring components based on physical measuring components to experiment with measurement manipulation functions.
Aggregator: An aggregator measuring component holds summarized usage from other measuring components. For example, aggregator measuring components could be configured to hold total consumption for each postal code within a service territory. Head end system processing statistics used by Oracle Utilities Smart Grid Gateway are stored as aggregated measurements for aggregator measuring components.
Refer to About Aggregations for additional functional information about aggregation measuring components.

Attributes used to define measuring components can include the following:

The measuring component type
The device configuration to which the measuring component is associated
Details concerning how the measuring component is read, such as the number of digits, the type of read out (dials or digital), the meter multiplier, etc.
The VEE groups used for validation and estimation of measurement data.
Refer to About VEE for details about the types of VEE groups supported.

Scalar vs. Interval

Beyond the four types described above, measuring components generally fall into one of two primary classes of: scalar measuring components, and interval measuring components.

Scalar measuring components are measured at unpredictable intervals. For example, "once a month" is not a predictable interval as the amount of time between reads in unpredictable and inconsistent.
Interval measuring components are measured at predictable intervals, such as every 15 minutes, every 30 minutes, every hour, etc.
The terms "interval size" and "seconds-per-interval" (SPI) are used to define the size of an interval measuring component's intervals.
Note: A device may have any combination of interval and/or scalar measuring components

Measuring Component Measurements

Measuring components are configured to measure specific types of quantities. These include:

Unit of Measure: The unit of measure for the quantity being recorded. Examples include kilo-watt hours (kWh), kilo-watts (kW), therms, cubic feet (CCF), temperature (Fahrenheit or Celsius), etc.
Time of Use: Modifiers for a given unit of measure that indicate a period of time during which a quantity has been used, such as On-Peak (meaning during a time when the greatest quantity of some consumable is being used), Off-Peak (meaning during a time when the least amount of some consumable is being used), etc.
Service Quantity Identifiers: Used to further distinguish between measured quantities that have identical UOM/TOU combinations, including situations in which the distinguishing identifier of a UOM is not accurately described as a TOU. Generally, SQI is only used when multiple measuring components measure the same thing, but in different ways. A meter that measures both generation KWH and consumption KWH could use SQIs to differentiate between the two.

The combination of UOM, TOU and SQI define what a measuring component measures. TOU and SQI are optional, but UOM must be defined for all measuring components. For example, consider a meter (as illustrated in the image below) with two measuring components, both measuring the same unit of measure (kWh), but each measuring component measures consumption in different time of use (TOU) periods (peak and off-peak).

Subtractive vs. Consumptive Measurements

Another attribute that defines how measuring components measure quantities is the distinction between subtractive and consumptive measuring components.

A subtractive measuring component's usage is equal to the current reading (also known as the Stop or End Measurement or Reading) minus the previous reading (also known as the Start Measurement or Reading). To put this more simply:

Usage = End Reading - Start Reading

Most residential scalar meters are subtractive and in some cases interval meters can be subtractive as well . The table below lists a series of measurements for a subtractive measuring component.


Date	kWh (Reading)	Usage
01/01/2010	0
01/31/2010	1000	1000 kWh
03/02/2010	1780	780 kWh
04/01/2010	2700	920 kWh

A consumptive measuring component's usage is equal to its current measurement. Most residential interval meters are subtractive. For scalar, consumptive measuring components are often used to measure demand, such as KW. The table below lists a series of measurements for a consumptive scalar measuring component.


Date	KW (Reading)	Usage
01/01/2010	0	0 KW
01/31/2010	10	10 KW
03/02/2010	10	10 KW
04/01/2010	13	13 KW