Digital Couplers for Explosive Atmospheres:
08 May 2008
R. STAHL's new explosion-proof digital I/O coupler for the ISbus system ensures a direct and consistent integration of basic sensors and actors. Thereby, intrinsically safe binary signals in a Foundation Fieldbus environment can be directly connected.
The coupler is suitable for use in Zone 1 and Zone 2. Besides eight channels for NAMUR specification or EN 60947-5-6 compliant Ex i input signals, four high-performance Ex i outputs are available.
The coupler can be used to connect e.g. proximity switches, contacts, indicator lights and, most notably, a wide range of magnetic valves. Up to four Ex i magnetic valves including two position feedback signals each can thus be directly integrated into a foundation fieldbus H1 network.
Extensive function block support ensures that such solutions benefit from particularly powerful FF technology features: the coupler provides not only DI, DO, MDI and MDO functions, but also advanced functions such as AI for frequency signals, CI for counters, and logic transducer blocks for logical interconnections of inputs and outputs.
The type 9413 coupler comes in a plastic or stainless steel enclosure. Wire breaks and short circuits are monitored on all channels and diagnostic messages are reported via the bus. Each output channel delivers a starting current of 30mA as well as 15mA holding current during regular operation. Types with status LEDs for all single inputs and outputs as well as the bus and power lines are optionally available. R. STAHL supplies two-wire or four-wire models fed via the non-intrinsically safe fieldbus; the four-wire coupler can also be used with a separate power supply on an intrinsically safe FISCO bus.
