Posted to News on 7th Oct 2021, 00:00
SIL 3 current drivers for hazardous areas
With new SIL 3 current drivers, Pepperl+Fuchs is completing its portfolio of SIL 3 isolated barriers for all types of signals – both as modules for DIN rail mounting and as isolating components for termination boards. Positioners in a SIL 3 application – which have always been available for digital signals from or into the field, and for analogue measuring signals – can now be connected directly to the controller with a single interface module. A SIL 3 application must no longer be realized via the elaborate path of redundant SIL 2 devices.
SIL 3 applications are also widely used in safety-related applications in which field devices in hazardous areas must be controlled using analogue signals. However, Pepperl+Fuchs asserts that no suitable isolated barriers with the ability to transmit signals between the controller and field devices have been developed to date. It may be possible to put a workaround with redundant SIL 2 devices in place, but a SIL 3-compatible interface module would require significantly less effort compared to a structure comprising two redundant SIL 2 modules. Last but not least, isolated barriers with SIL 3 suitability can even be useful in SIL 2 applications, for example, when the longest possible proof time is to be achieved.
The new, single-channel current drivers have a width of 12.5 mm, line fault detection, and a separate fault output. This allows users to build SIL 3 applications from a single portfolio, whether with SIL 3 isolated barriers or with redundant, SC3-capable SIL 2 modules.
A product selector for safety products can be found at www.pepperl-fuchs.com/safety-hub. This selector can be used to select suitable devices by function, signal type, SIL level or performance level (safety relays for safe shutdown both have SIL and PL levels).
