DIN EN 60079-18:2015-10

This part of DIN EN 60079 (VDE 0170) gives the specific requirements for the construction, testing and marking of electrical equipment, parts of electrical equipment and Ex components with the type of protection encapsulation "m" intended for use in explosive gas atmospheres or explosive dust atmospheres. The application of electrical equipment in atmospheres, which may contain explosive gas as well as combustible dust simultaneously, may require additional protective measures. It supplements and modifies the general requirements of DIN EN 60079-0 (VDE 0170-1). This part applies only for encapsulated electrical equipment, encapsulated parts of electrical equipment and encapsulated Ex components (hereinafter always referred to as "m" equipment) where the rated voltage does not exceed 11 kV. This standard does not apply to dusts of explosives or self-igniting substances which do not require atmospheric oxygen for combustion or react exothermically. The following changes in the standard are technically relevant: Subclause 7.8.3 "Protection against impermissible temperatures and destruction of cells or batteries" of the standard has been clarified to avoid possible misinterpretations. In addition, a new alternative has been included. In the case of "ma" equipment intended for use in areas where the "Da" level of protection is required, the maximum temperature must be determined for equipment installed in accordance with the manufacturer's instructions. The device must be embedded in dust at least 200 mm deep on all surfaces. The temperature rise of the device during the test can be a very slow process depending on the device and the resulting power loss. For this reason, it has been specified for devices with the "Da" protection level that the temperature is not stabilised until a temperature increase of max. 1K/24h has been reached. The responsible Committee is DKE/K 241 "Schlagwetter- und explosionsgeschützte elektrische Betriebsmittel" ("Electrical apparatus for potentially explosive atmospheres") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.