The EL9400 power supply terminal is used to refresh the E-bus via which the data exchange between EtherCAT couplers and Terminals takes place. Each EtherCAT Terminal requires a certain current from the E-bus (see technical data: "Current consumption via E-bus"). This current is fed into the E-bus by the power supply unit of the respective EtherCAT coupler. For configurations with a large number of EtherCAT Terminals, the EL9400 can be used to increase the power supply to the E-bus by 2 A.
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