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Speed of Communication between I/O Card and the control module

Hi all, so I read in several of documents that stated "communication between the I/O cards and the control module shall be via well-secured communication link with high capacity of data transfer and speed not less than 2 Mbps"

kindly please advice, is it that statement can comply with DV, please info exactly the speed of DV's communication.

thanks and best regards

Al Amin

4 Replies

  • Al Amin, please refer to Page 2 of this Product Data Sheet (PDS) which states network speed for DeltaV Area Control Network (ACN).

    Quoting from the PDS:

    "The DeltaV ACN supports the use of auto-negotiated 10-half, 100-half, 10 full, and 100-full duplex communications where the industry standard auto-negotiation process determines the highest speed at which two devices will communicate with each other.."

    Hope this helps.

  • In reply to MC_Chow:

    Hi Mr. MC Chow,

    Thanks for your answer Sir.

    please correct me if i'm wrong, so DeltV ACN provided communication between Workstation and Controller. then if I want to know, how fast exactly speed or data transfer between controller and IO module, is it same with DeltaV ACN support Sir.

    Thanks
  • In reply to al amin:

    Knowing "The Speed" is unnecessary. The bus is sized to support 64 io cards. Unless you are doing something really "weird" you will run out of CPU / memory capacity for you configuration long before the IO card bus will even get close to capacity.
  • In reply to al amin:

    The speed is always an interesting question. The real criteria is the update rate and its suitability for the application.

    DeltaV does not discuss the actual baudrate of the IO bus. It is a proprietary architecture and is designed to a specific purpose. This information is not available. What is important is that the localbus IO will update every 50 ms or better.

    DeltaV CHARM IO cards have a configurable update rate of 50ms, 100 ms, 250ms and 500ms. The DeltaV ACN will be 100 MB (Full Duplex) to CHARM IO and controllers.

    So if the requirement is to have a better than 2 MB link between controller and IO cards, we can do that with CHARM IO and a 100 MB link. For localbus IO, the protocol is proprietary and designed to deliver IO data to the controller at better than 50 ms as a closed system.

    I would indicate that the 2 MB bus speed does not apply because DeltaV localbus is a proprietary IO solution.

    Andre Dicaire