Description
The KFD2-SR2-Ex2.W is a 2-channel isolated switch amplifier (barrier) from Pepperl+Fuchs’s K-System range, designed for intrinsic safety applications where signals need to be safely transferred between a hazardous area and a non-hazardous control area. It accepts digital input signals from NAMUR proximity sensors or dry (volt-free) mechanical contacts in Zone 0/1/2 or Division 1/2 hazardous locations, and converts them into isolated relay contact outputs for the control side.
Each of the two independent channels provides a changeover relay output that switches state whenever its corresponding input signal changes, and the normal output state of each channel can be reversed individually via onboard DIP switches (S1, S2) to suit the application logic. A separate switch (S3) enables or disables line fault detection (LFD), which monitors the field wiring for breakage or short-circuit and reverts the relay to its de-energized (safe) state on a fault condition, with LED indication per NAMUR NE 44. The device is powered via 24V DC, either through a Power Rail system (which also enables a collective error message) or directly via terminals. Rated up to SIL 2 (SC 3) per IEC/EN 61508, it’s well suited for level, flow, and proximity switch monitoring in hazardous-area process plants, including oil & gas, petrochemical, and marine/offshore installations.