Module in plastic protective housing for connection of an esserbus/esserbus-PLus loop, but with galvanic isolation (GI). The galvanic isolation ensures that any disturbances on one loop do not interfere with the other loops and with the panel itself. Modules are locked mechanically without screws in the slots, just quick and easy. Hot plugging and automatic recognition of modules just by Plug and Play, makes start-up and maintenance easy to handle.