Omron NT31 Operation Manuals page 329

Fixed Displays
[Relationship with Other Elements]
318
S It is possible to make a single library data display by combining multiple fixed
display elements. If the display attribute for any of the elements in such a display
is "Flash" or "Inverse Flash", the display flashes in accordance with this setting.
The timing of the flashing is the same for all elements.
S Marks overlap with other fixed display elements in accordance with the order in
which they were registered. However, the way in which they overlap can be
changed with the Support Tool.
Section 7-4