J-Tech Engineering - Product Subpage - cdpd

By: J-tech Engineering  09-12-2011
Keywords: Modem, Autodialer

The Autodialer permits a remote DNP3 intelligent electronic device (IED) to transmit "Unsolicited Messages" or report-by-exception over a dial-up line. This capability is often a requirement for electric utilities using DNP3 and dial-up for Poletop RTUs and Independent Power Producers (IPPs).

Where dial-up access to a communication channel is required, there are currently two choices: A modem designed for DNP communications, able to intercept data and initiate a dial-out procedure; or a conventional modem in conjunction with the Autodialer module. In the latter case, any modem can be used to initiate communications, and the end result is a more cost-effective and modular system.

In a typical DNP system, when data must be reported through a communication channel, it is simply transmitted. The Autodialer sits between the DNP system and the modem, monitoring the system for communication activity. If activity is sensed, the Autodialer will sieze the channel, and establish a dial-up connection via the modem. Once this is established, control will be returned to the DNP system, and data may be transmitted. As this is a non-handshaked mechanism, the DNP system must be configured to transmit relevant data at least three times in order to give the system a chance to establish communication.

The unit has the following feature set:

  • Default communication speed of 9,600 bps.
  • DIN rail mountable enclosure.
  • Built-in self-test mechanism.
  • Reset Switch.
  • Up to 28V DC unregulated power input.
  • Field programmable using standard RS-232 cable.
  • No special software required, can be programmed using any terminal emulator.
  • 94V0 Rated PCB.

Keywords: Autodialer, Modem

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