Thanks to MSB on www.sps-forum.de
, I have had a breakthrough that means it can be solved without scripts and without any changes having to be made in the S5 program.
If you are converting an old OP project from Protool to WinCC Flexible, then you must read this !
Here is the scoop:
S5TIME values, have to be setup as "KT" tags.
In order to be able to set the value as seconds on the HMI, and for it to be interpreted as such in the S5 PLC, it is necessary to use the linear scaling in the tag. Same for actual values.
The linear scaling must work like this:
It is not a typo that the PLC must be 0-1000.
The WinCC Flex HMI then knows how to create the correct S5TIME value.
300 seconds on the HMI becomes 300 x 1 seconds in the PLC.
5 seconds on the HMI becomes 500 x 0.01 seconds in the PLC.
The linear scaling has to be setup manually for each S5TIME tag. WinCC Flexible does not do this for you when the Protool project is converted.
No info how to deal with setpoints in the 0.01 - 0.99 seconds region. lucky for me, all the timers are more than 1 second.