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14. Datalogging
14.1. Introduction
Datalogging allows memorizing values of your process, in order to visualize its history.
TB
OX
LT2
contains memory for recording historical values of Tags and events (see technical
specifications); the latter is what we call the database of
TB
OX
LT2
.
There are two categories of databases:
The Chronologies
hronologies are 'On event' recordings, by means of changes in Tags (also known as “Sequence of Events”).
Each event is recorded with time, date, Tag and its status or value.
The minimum resolution is 1 ms.
Example of ‘digital events’:
The changes of status of the Tag represent the events.
Example of ‘analog events’:
The variations of the Tag represent the events.
TB
OX
LT2
stores chronologies in 2 tables: one for digital data and one for analog data.
The size of the tables is defined in the General RTU properties, as described chapter 7.1.
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