Issue
Is it possible for multiple Automation Servers to be placed on the same backplane and use one power supply?
Some known issues in this unsupported configuration:
- Automation Server only partially discover the IO Modules
- Function Block Programs (FBP) remain in an unloaded state (see FBP Unloaded)
- EBO 2022 (v4.0) and higher, Alarm: IO Driver unexpectedly timed out
Product Line
EcoStruxure Building Operation
Environment
- Automation Server
- Power Supply
- SmartStruxure IO Modules
Cause
The terminal bases provides a path for communication between all connected units on the same backplane, as such the connection of two or more Automation Servers will cause communication issues between all connected units on that same backplane.
Resolution
From EBO 2022 (v4.0.1) due to changes in the Central I/O (CIO), checks are now made in the Automation Server to verify that the server is physically in SLOT 2, if this is not the case, then all Tasks are disabled, and will not run.
You cannot connect more than one Automation Server to the backplane. Only one Automation Server is allowed per power supply, the architecture is always "PS-AS-....." and after that I/O modules with additional PS units as needed, but only one Automation Server can exist on the same backplane.
Note that an alarm will also generate if you have the following configuration is attempted (also not supported)
- PS-AS-PS-AS
Alarms will only clear after a restart (warm) of the server
