Transmitter supply units type 9160 from R. Stahl's ISpac product line are now available as completely revised versions. Featuring new functions, the units are now suitable for an extended application range. In addition to a new model with an intrinsically safe interface for standard voltage signals, a SIL 3 version for functional safety applications according to IEC EN 61508 has been added. Users can design the sensor part of a safety function as a single-channel version according to SIL 3, or, in two-channel set-ups, extend the required test cycles. On top of that, a range of features has been optimised in all units from the 9160 and 9163 series. These include reduced power consumption, reduced attenuation during transmission of HART signals, consistently improved results for SIL applications allowing for more flexible planning, and a reduced signal delay, i.e. a faster reaction of the output signal to changes at the input. The transmitter supply units are available as one and two-channel versions, enabling space-saving installation in the cabinet. In addition to the connection of two-wire transmitters, the units also allow for the operation of three-wire-versions and the transmission of signals from four-wire-transmitters. HART signals are transmitted bidirectionally.