Low-voltage or medium-voltage switching and distribution system which is protected against contamination by dust and adverse influences from high air humidity, and a method for achieving the desired protection

摘要

For a low-voltage or medium-voltage switching and distribution system, which is to be protected against contamination by dust and adverse influences from high air humidity and is composed of a plurality or a multiplicity of switch panels (11...18) which are joined together, it is proposed to allocate an air-conditioning unit (20) to the switch panels or to a limited number of switch panels of the system, which unit is intended to suck in atmospheric air and to filter and to dry it; in this case, an air flow which emerges from the air-conditioning unit is intended to be supplied via a channel or pipe system (21, 22, 24), which is closed to the exterior, to each individual switch panel, causing a slight excess pressure therein in comparison with the air pressure of the external atmosphere, continuously or at intervals. The method which is used in this case is characterised in that atmospheric air is sucked in, filtered for dust and dried, or is not dried and then filtered for dust until after it has been sucked in, by means of the air-conditioning unit (20) which is to be allocated to the system, and said air is thereafter supplied via the said channel or pipe system (21, 22, 24), which is closed to the exterior, to the individual switch panels (11...18). An improvement in the method of operation of these measures can be achieved in that at least a part of the airflow supplied to the switch panels is supplied to the air-conditioning unit again. IMAGE