1. Now the speed is set from Downtime Monitor > Equipment > Attributes Management > Design Speed > Value: "15"; Unit of Measure: "Items / Minutes"; (as an example).
I can't change that value ("15") from a WinCC Tag (once the speed is set in Downtime Monitor it can't be modified unless a new version of Downtime Monitor project is created)
2. The speed is not automatically adjusted: the client must have the possibility to change this value regarding the production type of items of the machine (e.g. today: 15 items / minutes, tomorrow 60 items / minutes)
3. No, the speed should be set from a WinCC interface (PC) (operator input)
(I assume that this can only be done with a tag, but the problem is that this tag can't be set as "Value" in Downtime Monitor - point 1 of the answer).
unfortunately I've no ideea about Downtime monitor, but I assume that value goes to a PLC and that is the machine speed setpoint; that case I would define a new "place" into the PLC for the speed and set it from WinCC (pdl).