Abstract: An apparatus, in particular for simulating electrical sensor/actuator components, having a drive module (4), which provides a model (5, 6, 7) of the S/A component to be simulated and generates interface signals (U1n, Un) in accordance with the signals of the real S/A component to be simulated, and having a signal interface (12, 26) for each connection pin (28, 29) of the apparatus (1), which is driven by the real-time signals (8, 9, 10, 11) of the drive module (4) and generates, for each interface connection pin (28, 29), an interface signal (U1n, Un) corresponding to the electrical signals of the real S/A component, in which case the current direction or the energy flow of the interface signals (U1n, Un) can be directed, in a manner influenced by a control/regulation circuit of the signal interface (12, 26), towards the signal interface (12, 26) or away from the latter, with the result that the apparatus can optionally simulate a sensor or an actuator.