Could someone help me understand the difference between the EGD Configuration Server and the System Database that GE uses in the ControlST, Toolbox, and other automation software suites.

As far as I know, both can store information about EGD exchanges and devices configuration and have seen both being used on a single system, so I'm not very sure of what is the purpose of each one.

 

They do much the same thing; the difference is mainly generational. The SDB is from the Toolbox Classic, Mark VI and EX2100 era; the EGD configuration server is from the Mark VIe and ToolboxST era. You see both in systems with mixed Mark VI, Mark VIe, and EX2100 devices.

Primarily the SDB and EGD config servers are the central point for sharing symbols between parts of the system. Ie, the Mark VIe posts its global EGD variable list to the EGD config server, and all HMIs in the system can immediately see and use those variables.

Over time, the EGD config server has picked up a lot of non-EGD duties as well, like holding Alarm symbol and color information, and deploying HMI screen files to multiple HMIs in the system.

 

So, this means that on the new pure MarkVIe systems there is no more SDB?

And, that you mention about holding Alarm Symbols, does this substitute the TCI module of Toolbox Classic? or is this a completely different function?

 

Correct, you shouldn't see an SDB on a pure Mark VIe system.

TCI's function was a combination of protocol gateway and aggregating server for various protocols, including alarms. WorkstationST fills that role for the Mark VI and Mark VIe today (and older systems in certain retrofit scenarios).

What I meant about alarm symbols on the EGD config server is that the system-level configuration for alarms (ie classes, severity, sounds, colors, graphical symbols, etc) are shared via the EGD configuration server. The actual real-time data from the alarm queues on the controllers is aggregated by the WorkstationST alarm server, and passed to the individual alarm viewers on each HMI or engineering workstation.

A notable difference there from older generations is that HMIs don't use the CIMPLICITY alarm system; WorkstationST has its own alarm viewer application (and CIM plugin) that has much richer capabilities.