Reference, Installation, and Operations Manual

Section 6: Meter operation

3-9000-743 Rev S

June 2013

 

 

 

The Mark III meter firmware is segregated into distinct “tasks”, each of which is protected from the operation of the other tasks by the hardware MMU and the operating system. Any attempt of a task to access memory allocated to another task results in the shutting down of the errant task and a log of the task shutdown. The watchdog then performs a system warm start.

6.9.6Log transfer integrity

The Mark III optionally generates logs in standards-based XML files. These XML files are compressed into binary files and CRC protected for transfer from the meter to the user's PC where they are checked for CRC integrity and de-compressed before being further processed into reports for the user.

6.9.7Data value limit checks

All Mark III stored data resides in an internal database in which each data point has preprogrammed "sanity limits." The database enforces these limits on all values written to it, thus ensuring that under no circumstances will any data take on an illegal value.

6.9.8Configuration dependency checks

The Mark III checks for and enforces configuration dependency checks on most configuration values written to it (either by Modbus or to the native data point using Daniel MeterLink). For example, the AGA8 Detail method cannot be selected if the temperature input is disabled. This provides enhanced protection against inadvertent misconfiguration by the user.

Log transfer integrity

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