Patent ID: 8704681

Claim:
An arrangement for cross monitoring two independent generated signals, the arrangement comprising: a first calculating unit configured to calculate a value depending upon a signal value, drift value and a feedback value, wherein the signal value comprises information about an absolute value of a difference between the two independent generated signals; a determining unit configured to determine a larger one of the calculated value and a first predetermined value after calculation of the calculated value; a comparing unit configured to compare said determined larger value with a second predetermined value after determining the larger one of the calculated value and the first predetermined value; and a delaying unit configured, after comparing said determined larger value with the second predetermined value, to delay said determined larger value and change status of said larger value to become an updated feedback value to be provided to the calculating unit configured to calculate the value; wherein the comparing unit is arranged to output a warning signal if said determined larger value is equal to or larger than the second predetermined value so as to indicate that the independent signals differ too much from each other relative the second predetermined value.