The MTU is usually located in the same building as the HMI and typically connected on a 100MBit/s or Gigabit ethernet connection. The MTU collects data from DNP3, MODBUS and older MultiTrode remote devices and supplies this data to other systems supporting OPC-XML-DA, DNP3 or MODBUS.
The MTU communicates with the field hardware using open protocols. Communications can be via serial radio, ethernet radio, cellular data (GPRS & 1XRTT) and PSTN/cellular dial-up. In fact, because communication runs on RS232, TCP/IP and UDP/IP, most communication methods are supported.
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