System Safety Digital intelligent drives with the SERCOS interface offer outstanding protection against uncontrolled drive movements and excessive velocities. Using position values, command values, actual values and drive parameters, a SERCOS interface drive monitors itself and provides error warnings or error shutdowns, including forced orderly shutdown in the event of a malfunction or failure of the drive processor. Excessive velocities, overtravel, or axis runaway due to faulty or incorrectly transmitted position commands can be eliminated by logical monitoring by the drive of the values it receives from the control. Safety redundancy can be achieved by the control as it monitors the actual value data fed back from the drive via the SERCOS interface. This internal monitoring can ensure safe shutdown in the event of a communications failure.