Abstract: The operating condition of sliding components inserted between a slide or sprocket chain and a guide system for such chain is continuously monitored by an electrical loop conductor which passes through a plurality of sliding components. The electrical conductor is provided with an electrically insulating jacket which is preferably also heat resistant. The loop conductor is inserted into a monitoring circuit including a relay for activating an alarm when the loop conductor is either interrupted or when its insulation is damaged. This happens when any one of the sliding components through which the loop conductor passes, are sufficiently damaged. The alarm signal may also be used to stop the further drive of the sprocket chain.