Beckhoff EL2911 - Fig. 30 Worst-Case Reaction Time

Operation
EL2911 and EL2911-220048 Version: 2.0.0
Fig.30: Worst-case reaction time
This assumes that a signal change occurs at the sensor and is transmitted to the input. A communication
error occurs at precisely the moment when the signal is to be transferred to the communication interface.
This is detected by the logic following the watchdog time of the communication link. This information should
then be transferred to the output, but a further communication error occurs here. This error is detected at the
output following the expiry of the watchdog time and leads to the switch-off.
This results in the following equation for the worst-case reaction:
max Comm Comm Actuator
ReactionTime WD WD RT= + +
with, for example
15 15 20 50
max
ReactionTime ms ms ms ms= + + =