Impedance data

Impedance data for analog inputs

Unless otherwise defined in individual cases, the impedance data given for analog inputs refer to the operational, energized device status in the selected interface (if selectable).

The following must be observed:

• Devices may contain a self-test or cable break detection function. During execution, the impedance of the input channel may change considerably.
  The source device should compensate for this impedance change.
• If the device is de-energized, an impedance measurement (which necessarily applies a voltage to the input) leads to very specific leakage currents into the input circuit with its mixture of active and passive components. The impedance values determined in this way depend on the test voltage and may deviate considerably from the operating state.