R. Stahl has extended its range of field device couplers, adding two models for zone 2 installation and one zone 1 model with detachable terminals. The first device is the zone 2 Ex i FDC (Field Device Coupler), an Ex i fieldbus barrier especially designed for installation in zone 2. The unit allows users to connect up to eight intrinsically safe Fisco-compliant fieldbus devices from zone 1. Compared with a zone 1 fieldbus barrier, this solution achieves savings of up to 20 %. The zone 2 FDC model has also been optimised for zone 2 applications. Combined with a suitable fieldbus power supply, up to 12 field devices on the fieldbus in zone 2 can be operated as hot-swappable components with Ex nL, Ex ic or ic Fisco and short circuit protection. Featuring a special mechanical design, this solution has become even more compact and cost-efficient. All clamps are detachable, and all fieldbus connections have LEDs for short circuit diagnosis. The Ex i FDC for zone 1, which has been available for some time as a four- or eight-channel version, can also be equipped with detachable terminals. This considerably facilitates maintenance efforts, such as exchanging the intrinsically safe fieldbus devices or the Ex i FDC unit itself.