The 750-627 End Module for Internal Data Bus Extension is snapped onto the DIN-rail at the end of the module assembly like the standard 750-600 End Module. The assembly is terminated with the module, to which a connecting cable can be attached with an RJ-45 connector. Power to the internal electronics is supplied via internal data bus. One end module and at least one 750-628 Coupler Module for Internal Data Bus Extension are an operative unit. The fieldbus coupler/controller performs all diagnostic and commissioning tasks. Installation note (NOTICE): In order to guarantee safe operating conditions when using the 750-627/-628 Coupler Modules for Internal Data Bus Extension, these must be registered prior to startup with the couplers or PLCs (refer to manual for supported couplers/PLCs). You must use the WAGO Extension Setting Software for this (Download: www.wago.com). Please complete the manufacturing number matrix on the right-hand side of the couplers when updating the firmware and internal operating parameters.