Beckhoff EL3773 Documentation page 134

Commissioning
Fig. 151: Diagram signal delay (step response)
2.2 Signal delay (linear)
Keyword: Group delay
Describes the delay of a signal with constant frequency
A test signal can be generated externally with a frequency generator, e.g. as sawtooth or sine. A
simultaneous square wave signal would be used as reference.
The signal delay [ms, µs] is then the interval between the applied electrical signal with a particular amplitude
and the moment at which the analog process value reaches the same value.
A meaningful range must be selected for the test frequency, e.g. 1/20 of the maximum sampling rate.
134 Version: 2.5 EL3773