Can the Volume (source word) in "Project" be modified in e.g. page or any other value?
Yes, if you change Default CAT Calculation Unit in System Configuration > General Configuration > Settings > Defaults tab > Default CAT Calculation Unit.
Thank you, I cannot edit this setting with my profile as project manager, but we can do it with admin profile.
I have selected a new setting in "Base System Calculation unit", but in old project Volume is still as "source words".
Furthermore, the only choice I can see for "Default CAT Calculation Unit" is "source words".
Should we add a new calculation unit somewhere else before selecting the calculation unit?
Having only one calculation unit available would suggest that the others were disabled or removed.
You can review their status by going to System Values: Advanced > Calculation Units on the configuration page from your screen shot.
Activating existing units or adding new ones will require you to be an administrator.
Can this be done on a per project basis? Also, how would changing this unit affect automatic deadline calculations? (Which are based on it, if I´m not mistaken).
We do not know that yet, but these are surely valid questions to ask when designing a solution.
There is a development idea being discussed in parallel: http://xtrf.userecho.com/topics/601-copy-volume-for-fully-automated-projects/
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