A high voltage system, in particular in a motor vehicle, having a) a plurality of high voltage components that case carry an electrical high voltage, b) a plurality of insulation measuring devices that are each designed to measure an insulation resistance between one of the high voltage components and earth, and c) at least one monitoring unit for monitoring the insulation resistance of the high voltage components, wherein d) each insulation measuring device is designed to measure the insulation resistance routinely at short time intervals of less than 90 seconds, and e) the monitoring unit is designed to switch off the high voltage components if the measured insulation resistance is below a predetermined minimum value, characterized f) in that a ring-like monitoring line is provided that issues from the monitoring unit and sequentially connects the latter to the individual high voltage components and finally is returned to the monitoring unit, g) in that the monitoring unit is designed to transmit a query signal by way of the ring-like monitoring line, h) in that the monitoring unit is designed to check whether the query signal that is transmitted by the monitoring unit after passing along the ring-like monitoring line is received again by the monitoring unit, i) in that the monitoring unit is designed to switch off the high voltage components if the monitoring unit does not receive the query signal, j) in that the high voltage components are connected to one another by wiring harnesses (7, 8), wherein the wiring harnesses (7, 8) each contain a high voltage line (9, 10) and the monitoring line, and k) in that the monitoring line is routed through the wiring harnesses (7, 8) between the high voltage components, so that a fault-related disconnection of the wiring harnesses (7, 8) also results in disconnection of the monitoring line. a) a plurality of high voltage components that case carry an electrical high voltage, b) a plurality of insulation measuring devices that are each designed to measure an insulation resistance between one of the high voltage components and earth, and c) at least one monitoring unit for monitoring the insulation resistance of the high voltage components, wherein d) each insulation measuring device is designed to measure the insulation resistance routinely at short time intervals of less than 90 seconds, and e) the monitoring unit is designed to switch off the high voltage components if the measured insulation resistance is below a predetermined minimum value, characterized f) in that a ring-like monitoring line is provided that issues from the monitoring unit and sequentially connects the latter to the individual high voltage components and finally is returned to the monitoring unit, g) in that the monitoring unit is designed to transmit a query signal by way of the ring-like monitoring line, h) in that the monitoring unit is designed to check whether the query signal that is transmitted by the monitoring unit after passing along the ring-like monitoring line is received again by the monitoring unit, i) in that the monitoring unit is designed to switch off the high voltage components if the monitoring unit does not receive the query signal, j) in that the high voltage components are connected to one another by wiring harnesses (7, 8), wherein the wiring harnesses (7, 8) each contain a high voltage line (9, 10) and the monitoring line, and k) in that the monitoring line is routed through the wiring harnesses (7, 8) between the high voltage components, so that a fault-related disconnection of the wiring harnesses (7, 8) also results in disconnection of the monitoring line.