Device Coupler is designed for hazardous area applications.

Press Release Summary:

ATEX-certified TG300 TRUNKGUARD Device Coupler connects FOUNDATION Fieldbus H1 or PROFIBUS PA fieldbus devices in flameproof Zone 1 and 2 locations. Available in 4 or 8 fieldbus device models, coupler can accommodate additional field devices and link with other units to power as many devices as segment can support. TG300 has short-circuit protection, Automatic Segment Termination, and LED status indicators.

Original Press Release:

MooreHawke's Fieldbus Device Coupler Works in Hazardous Areas

TG300 TRUNKGUARD Device Couplers are ATEX-certified for use in Flameproof Zone 1 and 2 Locations

NORTH HILLS, CA-October 6, 2006-MooreHawke, a division of Moore Industries-International, Inc., announces TG300 TRUNKGUARD Fieldbus Device Couplers for applications in hazardous areas.

The TG300 TRUNKGUARD Device Couplers make connecting FOUNDATION Fieldbus H1 or PROFIBUS PA fieldbus devices in Zone 1 and 2 hazardous locations easy and inexpensive compared to traditional methods. The TG300 TRUNKGUARD allows "live" access for maintenance without de-powering the segment and eliminates the need for expensive Exd/Flameproof junction boxes.

The TG300 Device Couplers are available in models that individually handle four or eight fieldbus devices. Additional field devices can be accommodated by connecting the TG300's TRUNK-OUT connection to any adjacent TG300 TRUNK-IN connection. TG300 units can be linked together to power as many devices as the segment can support.

Special features for Zone 1 and 2 installations include a key-operated magnetic interface that allows individual fieldbus devices to be de-energized and worked on without de-powering the entire segment.

Full protection to IP30 as required for Zone 1 installation is provided by plastic shrouds and terminal entry fillers. This allows "live" access to the unit in Zone 1 areas. The shrouds have holes for a small screwdriver blade, and do not need to be removed for wiring.

Ready-fitted cable glands for armored or unarmored cable are made from nickel-plated brass. Compound seal glands for cable with inter-core spaces are also available.

IP66 Exe-approved enclosures are available in GRP (glass-reinforced polyester), aluminum and 316 stainless steel. The stainless steel enclosure has a vertically removable lid for easy access and bottom entry cable glands.

As with all MooreHawke TRUNKGUARD Device Couplers, the TG300 has short-circuit protection, Automatic Segment Termination, and LED status indicators.

MooreHawke's short circuit protection method prevents segment failure caused by single device faults. A unique "fold-back" technique automatically removes the faulted device from the segment, and does not permit any current flow to the device until the fault is corrected. All other fieldbus device couplers use a "current limiting" technique that holds a fault on the segment permanently; the additional current draw from the faulted circuit can overload the segment power supply or cause other devices on the segment to fail because of a lack of power.

The Automatic Segment Termination feature automatically determines which TG300 Device Coupler is the last one on the segment, and automatically applies proper termination. In the event that there is a cable break between TRUNKGUARD device couplers, the upstream device coupler senses this break and automatically applies its terminator until the repair has been made. This ensures that the remaining connected devices on the segment continue to communicate without any problems. This simplifies installation and commissioning during startup, and makes it easier to connect and disconnect TG300 Device Couplers for maintenance purposes.

For more information, contact Moore Industries-International, Inc., 16650 Schoenborn St., North Hills, CA 91343, U.S.A; Telephone: (818) 894-7111; FAX: (818) 891-2816; E-mail:; Web Site:

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