I'm working on designing a system and my team is debating the virtue of using a sub-system Allen Bradley PLC for a particular plant area. The proposal was to use a VIM to integrate the AB-PLC.
I'm pretty ignorant of VIM's, I only really know what they are, but not much about their capabilities. (PS- Just read the Mynah documentation for one of their products- doesn't look like this would be possible???)
Does anyone know, at a minimum, if AMS can use the DeltaV interface through a VIM to communicate via HART with devices on a PLC Sub-network. Has anyone ever done this?
Thanks for your input.
Brian
Brian McWhorter ISA:CAP OPC:SI PE:CSE
Brian,
As far as I know there would be no way for AMS to "see" any HART devices through the VIM. There are positives and negatives to using a VIM.
The VIM uses either Modbus TCP or Ethernet I/P and you are restricted to landing your data in DeltaV landing modules just as you would with a DeltaV serial interface. In fact the VIM will show up in DeltaV explorer as multiple serial cards.
If you need to interface to a PLC then the VIM is definitely the preferred approach but you will lose any ability to communicate to smart devices with AMS. If there are a significant number of HART/AMS/Profibus DP devices and you need to use AMS then you've only got two real opitons; 1) use HART multiplexers for the devices under the PLC and "bypass" DeltaV to commuicate with AMS. 2) omit the PLC all together, run the logic in DeltaV and have full AMS access to all devices.
hope this helps,
dewey
In reply to Dewey Kuchle:
Adding on to Dewey's reply
If the AB PLC is Contrologix with specific HART cards, AMS could interface directly to it for HART devices. It requires Spectrum Connects software. The best solution would be AMS via DeltaV (for HART, DP, and FF) but this is an option for HAR Tonly.