Timed Meter

A Meter has a reference (via an ORD) to a History in the Station database. Each Contract has a reference to a Meter and is used to calculate Invoice information.

Reference: this BFormat Property is used to reference the Meter on the Invoice Px page. By default, this refers to the name of the meterType being used. For example, if the Meter Type is selected to 'water', then the Invoice Px page Slot reference to the Meter would be 'slot:meters/water'. More information on engineering Invoice Px pages is covered here.
Meter Type: A list of Meter types.
History Identifier: The Meter History to be used. It's this history that's used to generate the Invoice.
Check Data: If the Meter History was recorded with an Interval, this setting will check all of the relevant history data before an Invoice is generated. The check ensures all of the data is present at the specified Interval.
Check data interval deadband: This Property works in conjunction with the 'Check Data' Property. If a check is being conducted, this is a deadband of time used in the Interval check.
Allow Negative Usage: If true, the invoice calculation will use negative interval consumption values. If false, the invoice generation will fail if any negative interval consumption values are detected. It may be common to have negative interval consumption values when metering electric loads with some form of on site power generation.
Ignore Hidden Recs If true, the invoice calculation will exclude any records from the meter history which have the hidden flag set. In circumstances where an individual history record has an incorrect value caused by an anomaly, simply setting that record to hidden will exclude the value from the calculation.
Status Filter: The Status Flags used to filter out invalid historic records when calculating an Invoice. When an Invoice is calculated, historical records are used. Any records with the matching Status flags (other than 'ok'), will be filtered out of the calculation.
Timed Meter Schedule: Select a Timed Meter Schedule to use. A Timed Meter Schedule encapsulates a standard Numeric Schedule component. It's this Schedule that dictates the different tariffs for in and our of hours.

A Meter can be disabled. Once a Meter is disabled, no more Invoices can be generated using this Meter.

A Meter also has other standard Niagara History views (History Chart, History Table etc).

Timed Meter Schedule Configuration

Each Meter references a Timed Meter Schedule. A Timed Meter Schedule encapsulates a standard Numeric Schedule. Instead of the Numeric Schedule doing any control, it's used as a reference for its time periods and rates. For instance, every Monday the Schedule will output a value of 3 between the hours of 9:00 and 11:00 A.M.

Let's have a look at this in more detail to see how part of the Invoice is calculated...

The Numeric Schedule has an output value of 3 between the hours of 9:00 and 11:00 A.M. In this case 3 is the 'in hours rate'.
The start value is the value from the Meter history before or equal to 9:00 A.M.
The end value is the value from the Meter history before or equal to 11:00 A.M.
Therefore, to calculate the Invoice essentially it's (end value - start value) * rate.

This calculation is repeated between the start and the end date the Invoice is generated for. The Invoice calculation also takes into account...

The default output of the schedule: the default output is the out of hours rate. For example, the above picture shows an our of hours rate of 2 between the hours of 12:00 and 9:00 A.M. The value calculated here will get used to compute the out of hours cost.
Special events: The normal hours can be 'overriden' by a special event. The special event can specify an alternative set of times and rates to be used for a day.
Effective period: The effective period gets taken into account when computing the invoice. If the start and end dates specified for calculating the invoice fall outside the effective period, the out of hours rate will be used (if specified).

More information on best practice for configuring Niagara Histories for Meters can be found here.