AMS OPC Server


OPC Client can connect to the AMS OPC Server and read values only Sync from Device/Cache mode. If the read mode is changed to Async IO  or  IOPCDATACALLBACK mode, I cannot read any values.  I would like to know what is preventing AMS OPC server to not respond to Async IO or IOPCDATACALLBACK mode?

  • Some additional information about Integration Tools in AMS Device Manager. This enables XML web services and also OPC-DA. The XML pulls data from the database of AMS Device Manager. OPC-DA is used to get dynamic data directly from the device in the field.

    The issue is AMS Device Manager is a window into the device. You see parameters like range values that are stored in the database. You also see dynamic variables which are only displayed and are NOT stored in the database.

    HART is 1200 baud. It takes about 7 seconds to call a device and read a dynamic variable. You may be able to get say 75 of these dynamic variables and be ok, but if you will pull maybe 100 or  more parameters the PC will lockup. Essentially you make requests for data faster than we return the results from the devices; so the memory will overrun.

    AMS device Manager is NOT a process historian. If you need dynamic data from devices, you should request it from the DCS, PLC, gateway, HART multiplexer if it supports OPC, etc. Do NOT get this data from AMS Device Manager.

    The Data Server available with v14.5 FP2 also gets data from the database; NOT the dynamic variables from the device. It allows you to map data through MQTT bs having to make XML calls. Some database data is available today. In the future, say April 2024, we should have access to all data in the database.

    Eric Snyder | NA PAM Platform Sales Development | Process Systems & Solutions

    Emerson Automation Solutions