The Historian OSI PI collector does not modify the time stamps placed on data samples by the OSI PI Data Archive. As a result, if your system clocks are not synchronized on both your OSI PI Data Archive server and Historian server, it is possible that Historian may receive data samples in the future or in the past.
PITimestamp Data Type not Supported
The PITimestamp data type is not supported by the OSI PI Collector. If you attempt to collect a tag with the PITimestamp data type, an error will be logged and the value will not be collected.
PI Digital States/Enumerations
Upon manual startup of the OSI PI collector (that is, a restart via the services control panel), the PI Digital States are imported into Historian. When enumeration tags are subsequently configured (digital tags in OSI PI), the matching enumeration is set as well and data will then be matched against the enumeration.
For a PI digital tag, we create a Historian enumerated tag and for a PI digital set. If the PI tag contains values from its enumerated set, then it values are written correctly in the Historian tag. But, in some special cases, the PI tag may contain values from a special set (System set). Historian does not support these values as we cannot assign two enumerated sets to one tag. In these cases, the values are written as 0- Bad quality.
The Historian PI Collector has the ability to connect to an OSI PI Collective (PI redundancy). This allows data to be moved to Historian to prevent data loss.
