Hello Ronald,
If you check the API Explorer under TASK you will see, that there are different fields, that have something to do with the task duration.
- duration (double)
- durationExpression (string)
- durationMinutes (int)
- durationType (string / enum)
- durationUnit (string / enum)
Clicking on each of those entries in the API Explorer will show you some details.
I just tried to update a task duration using the module Update record. It simply worked passing an integer to the field duration.
Before I used the Read a record module passing * as output to get all fields. There I recognized, that the task I updated was set like this:
durationType: A
durationUnit: H
The field durationMinutes was calculated automatically.
I would suggest playing around a bit, perhaps the durationType can be showstopper when trying to simply update the duration field...
I hope I could help a bit.
Regards
Lars