Reference, Installation, and Operations Manual

Section 6: Meter operation

3-9000-743 Rev S

June 2013

 

 

 

6.6Archive logs

The Mark III meter provides five types of data logs (daily, hourly, audit, alarm, and system logs) which meets the requirements set forth in the American Gas Association / American Petroleum Institute Manual of Petroleum Measurement Standards, Chapter 21.1, Flow Measurement Using Electronic Metering Systems (ref. [4]).

Each log type is discussed in detail below (Section 6.6.1 through Section 6.6.5) followed by instructions on using Daniel MeterLink to read (and optionally save) meter log records (Section 6.6.6).

Note that reading log records is an optional feature as described in general in Section 430 and in detail in Section 4.1.4.

Daily and hourly log data point actions

Five different log data point actions are supported by the daily and hourly logs: snapshot, average, flow-gated (average), totalize, and macro as described below:

•Snapshot: causes the data point’s value at the log time to be recorded.

•Average: causes the data point’s average value over the log interval (day or hour) to be recorded.

•Flow-Gated: causes the data point’s flow-gated average value over the log interval (day or hour) to be recorded. A point’s flow-gated average is the average of its values when the flow is above the low-flow cut-off. If the flow does not exceed the cut-off during the interval, then the data point’s flow-gated average is the same as its regular (non-flow- gated) average.

•Totalize: causes the data point’s accumulated value over the log interval (day or hour) to be recorded.

•Macro: causes the (boolean) data point’s ‘latched’ value over the log interval (day or hour) to be recorded. A (boolean) data point’s latched value indicates if the point was ever TRUE during the log interval (where a TRUE value is represented by a 1 and a FALSE value is represented by a 0). This allows a group of boolean data points to be grouped into a single integer value where each bit represents the latched value of a single boolean data point.

6.6.1Daily log

The Mark III meter stores a daily log record once per day at the specified contract hour. (Refer to Section 5.10.1 for information on specifying the ContractHour data point.)

The meter can store up to 365 daily records. The user can select whether old, unread records can be overwritten by new records when the log becomes full via the data point DoOverwrit- eUnreadDailyLog. This point can be modified using the Daniel MeterLink Tools - Edit/Compare Configuration screen. The default is to overwrite old, unread records. Refer to Section 6.6.6 for information on reading records and marking records as read. The data point IsDailyLogFull indicates whether or not the daily log is full and cannot overwrite old, unread records.

Archive logs

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