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Insight

Dynamic Arc Recognition and Termination

Wed, 01/25/2012 - 08:34

Based on the existing technology of dynamically acting power supplies, the world market leader for intrinsic safety and explosion protection company Pepperl+Fuchs’ dynamic arc recognition and termination (DART) technology means that available power is dramatically increased compared to previous intrinsically safe (IS) electronic systems. When a potentially threatening condition occurs, such as the opening or closing of an electric circuit, DART ensures that the circuit is in a safe state before critical levels are reached. This works by recognizing the typical voltage and current pattern that indicates the development of a spark and cuts off the power supply in a few microseconds, thereby ‘extinguishing’ the spark before it is able to develop sufficient energy to ignite potentially combustible materials in hazardous areas where the technology has been installed. This differs from existing IS technology because it allows much more power to be used in an installation; previous IS methods involved limiting power availability. DART technology means that up to 50 watts can be supplied to devices within the explosive zone.

Both Pepperl+Fuchs and R. Stahl have signed a license agreement for using new DART technology. The open licensing model allows for the unlimited use of this patented technology in order to support its fast international acceptance. Both companies also hope that DART technology will soon be standardized internationally.

CURRENT, VOLTAGE AND POWER OF A BREAK SPARK

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There are many potential applications for DART, which is currently in the development phase, and as a result Pepperl+Fuchs is concentrating on two different versions of the technology. DART Power is designed for point- to-point connections, which will enable the maximum available power of 50 watts on a 100m cable. The second is DART Fieldbus, which is optimized for maximum cable length while retaining the potential to connect up to 20 fieldbus instruments to a segment. The company is looking for development suggestions from users of Pepperl+Fuchs technology in order to tailor the technology to specific applications.

CURRENT, VOLTAGE AND POWER OF A SPARK INTERRUPTED BY DART

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