The new CPUs and Power Modules in the Remote I/O IS1+ system from R. STAHL are now also available for installation in Zone 1. This means that the extensive range of functions offered by the Zone 2 version, such as integrated support for PROFIBUS DP, PROFINET (CC-B), EtherNet/IP, Modbus TCP and OPC UA, can now also be used in Zone 1.
Although IS1+ has, until now, been restricted to eight I/O modules for Zone 1 installations, the new solution have now made it possible to double the number of I/O modules that can be connected to 16 and therefor 128 analogue or 256 digital signals can be handled by one system. This also makes the system even more cost-effective to operate. In plants with both Zone 1 and Zone 2 installations, in particular, the additional engineering work required is significantly reduced because Zone 1 and Zone 2 systems can be handled almost identically in terms of their design and planning.
Unlike the Zone 2 CPU, the Zone 1 version uses intrinsically safe communication interfaces in order to enable extensions, modifications or maintenance work during operation, even in explosive atmospheres – without any time-consuming approval processes or shut downs. The PROFIBUS DP connection is still based on the intrinsically safe RS485-IS standard. For the Ethernet protocols, IS1+ uses the new, standardised Ex i version for 4-wire Ethernet: 100BASE-TX-IS. In order to bypass the length restriction of 100 m for copper-based Ethernet, a Zone 1 media converter is just in development, which converts the intrinsically safe 100BASE-TX-IS in FO 100BASE-FX for distances of up to 30 km. It will be available springtime 2023.
As well as the communication protocol, which can be adjusted by the user, all additional innovative functions of the Zone 2 version have been ported to the Zone 1 version; take, for instance, the expanded ambient temperature range of -40 to +75 °C in both horizontal and vertical mounting positions. Also included is integration into ring topologies with MRP or DLR, as well as support for a range of redundancy concepts like CPU & Power Module redundancy or PROFINET S2 (Conformance Class B).
The comprehensive diagnostics, including NE107 «Maintenance Required» signalling for predictive maintenance, are accessible for both the CPU and Power Module. All diagnostics and system information plus HART-field device data is available as a second channel via the process bus or Ethernet network, as well as via a separate ServiceBus. Access can be obtained via the typical FDT/DTM means or via the, integrated OPC UA interface.