Rockwell Automation 1756-HIST2G FactoryTalk Historian ME 2.2 - Manual (Page 289)

F • D ESIGN C ONSIDERATIONS AND L IMITATIONS
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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.
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For information about how configure the FactoryTalk Historian SE or PI server 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.
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Only the last version of the backup configuration is stored.
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Do not edit the backup and recover XML files.
System Connectivity
This section lists considerations related to system connectivity.
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The maximum number of modules per chassis is 2.
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Number of controllers that can transfer data to one module is 4.
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The maximum number of modules that can be used to transfer data
simultaneously from the ME to one SE server is 20.
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The maximum number of clients that can have simultaneous access to the module
is 5. This number includes a web browser, the FactoryTalk Historian SE or PI
server, and any other client tool. After the limit is reached, any client will be
denied access to the module based on total number of connections exceeded.