Setup of Honeywell Modbus Funace Topics

I have just started with Ignition and am trying to make sure I am doing this in the most efficient manner.

I have a bunch of PID loops that are contained in a multiple Honeywell HC-900 Controllers. Each controller has a fixed modbus map that is available from Honeywell.

In order to get the tags into ignition I completed the following steps.
Created the Modbus connections to each controller.
Created an address map for each modbus controller that reflects a majority of the tags that I needed.
Created a UDT that has the majority of the Modbus mapping in it. Since all of the modbus registers are in the same order with a different start address, I used the parametization to allow me to only enter the PLC name and the starting address. I created all my history setup and alarm profiles in this so I can config and go in one place.

This is where my first question comes in, how liberal or strict should I be in getting that mapping to align with only the tags I plan on using? Should I enter a large range so that I have all the tags and or should I narrow it fairly close down. I am a little confused about efficiently polling the modbus device. Does it make much of a difference if I poll from individual tags without mapping?

Does this seem like the most efficient way to do this or should I be doing something completely different. I am new to all of this and appreciate any help or guidance.

The mappings in the devices are a convenience for browsing in the designer. They don’t actually impact communications with the device. The driver will by default span multiple registers automatically if they are near each other and have the same polling pace (different scan classes with the same pace are merged).

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