EtherCAT fieldbus remains in the state "Pre-operational"

Frage:
What might be a reason that the EtherCAT fieldbus remains in the state "Pre-operational" after a restart of a Lenze controller (Inverter i550 / STO)?
 
Antwort:
Please see the attached document.

URL for linking this AKB article: https://www.lenze.com/en-de/go/akb/201800217/1/
Kontaktformular