Emerson Exchange 365

Hi Emerson Community,

I have a couple of questions regarding the following interface setup:
We are trying to set up a modbus interface to a couple of our Heat Trace Controllers from our DeltaV DCS. The Heat Trace Controller is an nVent Controller by Raychem (nVent was formerly known as Pentair). I believe the nVent Controller is capable of Modbus RTU only (RS-485). The nVent Controller uses an extended register scheme. Our DeltaV System is a rev13.3.1 with S-series DeltaV Controller Hardware.

My understanding is, I have the following two options available to set this interface up:

1. I can interface over a Deltav serial card but will need the 'enhanced modbus rtu' driver for access into the extended modbus addresses.
2. I can use a VIM to interface over modbus tcp and then place a protocol converter in between the VIM and this nVent Controller.

Questions:

1. For Option #1described above, can I go straight from the serial card to the nVent controller?  What are the drawbacks with Option #1? (I'm assuming the main drawback is data limitations, since a VIM is capable of 4x as much).
2. For Option #2 described above, would I still require the enhanced modbus driver to access the extended registers, using the emulated serial cards
3. Is there another option or something that I may be overlooking?

I appreciate any help in this matter!