Rockwell Automation 1756-HIST2G Historian ME 2.1 - Manual (Page 277)

F • D ESIGN C ONSIDERATIONS AND L IMITATIONS
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To calculate the total events per second, tags divided by the scan rate have to be
summed up per scan class for the module:
For example, if the Data Collection configuration is based on two scan classes, one
with 200 tags at a 250ms scan rate and one with 600 tags at a 2s scan rate, the total
events per second is 1100.
200/250ms + 600/2sec <-> 200/.25sec + 600/2sec <-> 800 + 300 events/sec = 1100 events/sec
Time Synchronization
This section lists considerations related to time synchronization.

For information about how configure the FactoryTalk Historian SE as an NTP
time server, refer to Microsoft’s knowledgebase article “How to Configure an
Authoritative Time Server in Windows” at http://support.microsoft.com/kb/
816042/en-us
A sample public NTP server is located here: 0.north-america.pool.ntp.org.
Backup and Recovery
Module configuration data can be backed up to a compressed file.

Only the last version of the backup configuration is stored.

Do not edit the backup and recover XML files.
System Connectivity
This section lists considerations related to system connectivity.

The maximum number of modules per chassis is 2.

Number of controllers that can transfer data to one module is 4.