Imperial Valley Resource Recovery (IVRR) is a biomass-to-electric power plant delivering more than 16 MW of power onto the grid. In the spring of 2004, during a maintenance shutdown控制工程网版权所有, the electrical paralleling switchgear suffered a major electrical explosion that destroyed the connection to the grid and adjacent Control room electronics. As a result of the extensive damageCONTROL ENGINEERING China版权所有, Dynalectric Co. was contracted to provide designCONTROL ENGINEERING China版权所有, installation, programmin

g, and support to update the prior electrical and process telemetry, and ultimately incorporate Ethernet-based Modbus RTU communications and controls. The new Ethernet-based system has been in place for

        To stay on budget, some equipment was reused. New Ethernet equipment was installed in the old control system cabinets.

        approximately one year with the generator again 'on-line' and with significant improvements adapting Ethernet-based I/O Net Concentrator Systems (NCSs) from Moore Industries.
        Flash and boom
        Imagine that you are in the control room, when suddenly the adjacent ac power panel room lights up brilliantly white, accompanied by a loud boom. A plasma fireball bursts out of the ac power panel main contactor area. It immediately vaporizes the paint off of the nearby power cabinets and melts the aluminum overhead cable trays. All your control room cables carrying signals to and from the facility are incinerated.
        You exit your workstation—after all, the melted cables have definitely shut down the facility. The fireball remains for a few secondswww.cechina.cn, but there is no subsequent flame. The metal walls of the contactor room do their job so nobody is injuredwww.cechina.cn, but there is soot everywhere.
        The fireba