Abstract: A monitoring device for monitoring an impedance of a protective conductor. The monitoring device has a first voltage divider for connection to a voltage source including a series connection to a first resistor and a second resistor. The second resistor has a resistance value which corresponds to a threshold value for the impedance of the protective conductor. A second voltage divider includes a series connection to a third resistor and a bridge diode and a connection to the first resistor at a first end of the third resistor and connectable to a second end of the third resistor and to the protective conductor. A measuring device is provided for the detection of a bridge voltage between a first node and a second node if the impedance of the protective conductor is greater than the value of the second resistor.

Abstract: A monitoring device for monitoring an impedance of a protective conductor. The monitoring device has a first voltage divider for connection to a voltage source including a series connection to a first resistor and a second resistor. The second resistor has a resistance value which corresponds to a threshold value for the impedance of the protective conductor. A second voltage divider includes a series connection to a third resistor and a bridge diode and a connection to the first resistor at a first end of the third resistor and connectable to a second end of the third resistor and to the protective conductor. A measuring device is provided for the detection of a bridge voltage between a first node and a second node if the impedance of the protective conductor is greater than the value of the second resistor.

Abstract: The invention relates to a system unit of a computer. The system unit has a plug-in card populated with components and a fan which supplies an air flow to an air ducting body arranged in the system unit. The air flow is provided for cooling the plug-in card which is arranged in the system unit essentially parallel to the air ducting body. Cooling of the plug-in card is improved in that the air ducting body has a central conduit and a first and a second side conduit. The side conduits are provided with a plurality of openings which are arranged in a row and aligned essentially parallel to heat sinks arranged on the plug-in card. The central conduit has a constriction for the admission of air.

Abstract: The invention relates to a system unit of a computer. The system unit has a plug-in card populated with components and a fan which supplies an air flow to an air ducting body arranged in the system unit. The air flow is provided for cooling the plug-in card which is arranged in the system unit essentially parallel to the air ducting body. Cooling of the plug-in card is improved in that the air ducting body has a central conduit and a first and a second side conduit. The side conduits are provided with a plurality of openings which are arranged in a row and aligned essentially parallel to heat sinks arranged on the plug-in card. The central conduit has a constriction for the admission of air.