An analog input module includes an activation unit, an analog/digital converter, an input circuit with a first input and a second input and a voltage divider disposed between the first input and the second input. The activation unit is connected to the first input and the second input and is connected upstream of the analog/digital converter. The voltage divider has center tap which is connected to a first comparator input of a comparator of a closed-loop control unit. The closed-loop control unit has a switching device disposed between the second input and a reference point. The comparator includes a second comparator input which is connected to a reference source. The comparator has a control output which is connected to a control input of the switching device. The closed-loop control unit is configured such that the switching device enables or disables a current path to the reference point.