BECKHOFF EL9xxx - Manual (Page 46)

Product overview
Fig. 38: EL9550
The EL9540 system terminal contains an overvoltage filter for the 24 V field supply, the EL9550 for the 24 V
field and system supply. The filter protects the EtherCAT Terminals from line­bound surge voltages that can
occur due to high­energy disturbances such as switching overvoltages at inductive consumers or lightning
strikes at the supply lines.
The EtherCAT Terminals EL9540 or EL9550 protect the terminal station from damage in particularly harsh
environments. The ship classification organisations require the use in shipbuilding applications and in the
onshore/offshore sector.
EL9xxx 46 Version 3.1