CP600 display - Trend: Page duration

In CP600 displays, I am having a hard time changing the "Page duration" in "History trend" while running the program. The syntax in the dropdown menu is "1 min, 10 min, 1hour, 2hours ..." but I do not know which data type this is. I would like to use a "Combo box" with theese alternatives. Does anyone know how to do this?

Best regards

Jostein