Connecting device for transmitting electrical energy from a spatially fixed conductor rail to a tapping device which can be moved along the conductor rail or is also spatially fixed, comprising: - at least one connection housing , wherein the line rail is mechanically connected to the pick-off device via the connection housing , the connection housing comprising at least one base support on which connection components are mounted on a mounting surface , - a current pick-up device which comprises sliding contact elements for picking up electrical energy from the conductor rail , the sliding contact elements being guided through the base support and having, on a side of the base support facing away from the conductor rail , a contacting region by means of which at least one printed circuit board of the connection device and/or at least one printed circuit board of the pick-up device and/or at least one motor printed circuit board is electrically conductively contacted, wherein the connection housing has contacting shafts on a side facing the conductor rail , which contacting shafts are open at least in places in a direction parallel to the conductor rail , at least one sliding contact element running along an inner surface of each of the contacting shafts , so that an electrical line of the conductor rail , which is in each case assigned to a contacting shaft , can be contacted within the contacting shafts , and further wherein the sliding contact elements in the region of the contacting shafts are of wave-shaped design, and further wherein the contacting shafts are designed in the form of a plug-on device on the individual lines, characterised in that the connection components comprise at least one terminal and a protective circuit , and in that the protective circuit is fixed on the mounting surface of the base support . - at least one connection housing , wherein the line rail is mechanically connected to the pick-off device via the connection housing , the connection housing comprising at least one base support on which connection components are mounted on a mounting surface , - a current pick-up device which comprises sliding contact elements for picking up electrical energy from the conductor rail , the sliding contact elements being guided through the base support and having, on a side of the base support facing away from the conductor rail , a contacting region by means of which at least one printed circuit board of the connection device and/or at least one printed circuit board of the pick-up device and/or at least one motor printed circuit board is electrically conductively contacted, the connection housing has contacting shafts on a side facing the conductor rail , which contacting shafts are open at least in places in a direction parallel to the conductor rail , at least one sliding contact element running along an inner surface of each of the contacting shafts , so that an electrical line of the conductor rail , which is in each case assigned to a contacting shaft , can be contacted within the contacting shafts , and further wherein the sliding contact elements in the region of the contacting shafts are of wave-shaped design, and further wherein the contacting shafts are designed in the form of a plug-on device on the individual lines, characterised in that the connection components comprise at least one terminal and a protective circuit , and in that the protective circuit is fixed on the mounting surface of the base support . <EOS>