When designing Wi-Fi and other wireless systems that can be managed uniformly and centrally, including in hazardous areas, all potential ignition hazards posed by wireless equipment must be circumvented using special protective measures. For this reason, R. Stahl equips conventional wireless devices for use in zone 1/21 by installing them in flameproof enclosures so that they are explosion-protected. To realise safe, uncomplicated cabling, the enclosures feature a separate Ex e connection chamber. The tested units, which have been certified for wireless use around the world, also feature intrinsically safe bushings for connecting any desired industrially capable antenna. The HFisolators from their 9730 series also guarantee optimum safety; as well as Wi-Fi, they support a wide range of additional wireless standards such as LTE, Bluetooth, LoRaWAN, WirelessHart and ISA100.11a. As a cost-effective alternative for zone 2, the 9851 series features an enclosure system with Ex nR type of protection and a separate connection chamber. In comparison with Ex d solutions, these enclosures are up to 70 % lighter. In addition, they allow the installation of wireless modules that only have internal antennae, like many Wi-Fi or RFID readers.
R. Stahl Schaltgeräte GmbH, Waldenburg, Germany
