Hello Doug,
The default setting for writing outputs for the Modbus (Zetron) object is to do so immediately. I.e., whenever you attempt to write to an output, you initiate the polling of your rtus, essentially.
If you rather want to make a bunch of changes and then write them together in one poll, you must uncheck this 'write outputs immediately' setting (under Advanced), and use the Poll datamember, with a PushButton for instance.
Hope this helps. Please write back if I misunderstood your question.
Regards,
Khalid