An enclosure arrangement, with protection against touch, of a power electronics appliance, more particularly of a frequency converter (31, 51) and its additional devices (12, 13), which solution contains an enclosed power electronics appliance and one or more enclosed additional devices installed in connection with it, which enclosed power electronics appliance and additional devices are modules, which can be fitted to be installed in combination one above the other such that the protection against touch of the appliance entity formed is as great as or higher than the protection against touch of the separate appliances.