The invention relates to a
digital input assembly for an
automation device, comprising: - an input terminal (E1, E2, E3) functioning as a
digital input, - a ground connection (M), - a detection means (PE) having an input (1, 2, 3) for an input
signal (I1, I2, I3) present at the input (1, 2, 3) and designed to detect a
logic level of the
signal present at the input (1, 2, 3) via the input terminal (E1, E2, E3), the detection means (PE) furthermore has a level output (P1, P2, P3) at which the detected
logic level is output, wherein to avoid incorrectly detected logic levels between the input terminal (E1, E2, E3) and the ground connection (M) before the input (1, 2, 3) a first
diode (D1, D2, D3) is connected in series with a first
suppressor diode (D4) and also a first counter
diode (D11, D22, D33) is connected in series with a second
suppressor diode (D3), as a result of which a first protective path (S1) for a positive interference
coupling-in and a second protective path (S2) for a negative interference
coupling-in are realised, additionally a preresistor (R11, R12) for current limitation is arranged between the input terminal (E1, E2, E3) and the diodes.