Issue
Automation Server - Warm and Cold Start differences
Product Line
EcoStruxure Building Operation
Environment
Building Operation Automation server
Cause
The explanation on the differences between a warm start and a cold start in the documentation and web help may not be clear to some.
Resolution
Warm Start: Restarts the controller's application
Cold Start: Restarts the controller's operating system
An Automation Server can be warm/cold started from Workstation or by using the reset button on the Automation Server. Refer to Reset Functions on Web Help for an explanation of the differences between warm and cold starting the AS.
Basically, you can set the Retain Levels for variables in Building Operation
to 'No', 'warm start' or 'cold start'. To change the retain level of a variable and go to its properties.
- Click on the gear icon.
- Set the retain level of the variable.
1. Retain level set to 'No' - The variable is reset to the value set when the object was created.
When you create an Analog Value object, the value of the newly created object is '0'. A user can set this to another value. When retain level is set for this Analog Value object, after a warm or cold start, the value of this object will default back to '0'.
2. Retain level set to 'Warm start' - The value is set back to the last value set by the user.
If a user change the value of an Analog Value object to another value and save, after a warm start, the object will return to the last value set by the user.
3. Retain level set to 'Cold start' - The value is set back to the last value set by either the user or the system (for instance by a program).
The operation is similar to the warm start but in this case, the last value set by the system will also be retained.
