IEC 62784-2019 pdf free.Vacuum cleaners and dust extractors providing equipment protection level Dc for the collection of combustible dusts- Particular requirements.
For the purposes of this document，the terms and definitions given in IEC 60079-0,lEC 60079-31,IEC 60335-2-69 and the following apply.
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3.1 combustible dust finely divided solid particles，500 um or less in nominal size，which may form explosivemixtures with air at standard atmospheric pressure and temperatures.
Note 1 to entry: This includes dust and grit as defined in ISo 4225.
Note 2 to entry: The term solid particles is intended to address particles in the solid phase and not the gaseous orliquid phase, but does not preclude a hollow particle.
3.2 explosive dust atmosphere mixture with air，under atmospheric conditions，of flammable substances in the form of dust,fibres or flyings which,after ignition， permits self-sustaining propagation.
Note 1 to entry: Minimum ignition energy values for common dusts can be found in IEC 60335-2-69.
[SOURCE:IEC 60050-426:2008,426-01-08，modified -The note to entry has been added]
3.3 mobile machine transportable equipment machine that is capable of being moved from one location to another.
4.1General Vacuum cleaners covered by this document minimize the risk of ignition during normaloperation (intended use).By fulfilling the requirements specified in this standard, any misusewhich can reasonably be anticipated is addressed. The requirements given in this standardapply to each machine，including all accessories, such as nozzles，hoses,unless otherwisestated.
4.4supply connection and external flexible cords
Supply cords and plugs shall comply with lEC 60079-31 for EPL Dc if the connection isintended to be made within the hazardous area.
4.5 Connection facilities and termination compartments
Terminal compartments for external conductors shall comply with lEC 60079-31 for EPL Dc.
5 Type verification and type tests
Compliance with the requirements of this standard is checked by inspection, examination andtests, as appropriate.
End-to-end hose resistance of the hose assembly shall be less than 1 MQ.
6 Routine tests
The manufacturer shall also carry out routine tests required by the standards listed inClause 2 which were used for the examination and testing of the equipment and areappropriate for this product group with EPL Dc and are applicable for this product group.
7 Marking and instructions
Marking shall be in accordance with lEC 60079-0.
The symbol provided for the “type of protection used” for the appliance is to be “62784″.
An example for this marking is “Ex 62784 lIC T135°C Dc”.IEC 62784 pdf download.