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 analog 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 analog signals. However, 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. 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 current drivers for the DIN-rail-based K-System are also available with spring terminals

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).


For termination-board mounting: the SIL 3 current driver of the H-System