UL-60079-5:2016 pdf free download – STANDARD FOR SAFETY Explosive Atmospheres – Part 5: Equipment protection by powder flling “q”.
4 Constructional requirements
4.1 Containers
4.1.1 Closing and sealing
4.1.1.1 General
Containers of electrical equipment, parts of electrical equipment or Ex components protected by powder filling “q” shall be filled and sealed at the time of manufacture. The closing and sealing shall be the methods of 4.1.1.2 or 4.1.1.3.
4.1.1.2 Containers permanently sealed at the time of manufacture
The container shall be permanently sealed at the time of manufacture and shall not be capable of being opened without leaving visible evidence that the container has been opened. The container shall be marked in accordance with Clause 6, item a).
NOTE Suitable techniques that can provide visible evidence of containers being opened are, for example, welding, soldering, cemented joints, rivets, cementing of screws, or lead-seal safety-wiring of screws.
4.1.1.3 Containers intended to be opened for repair
Electrical equipment, parts of electrical equipment, or Ex components that are designed to be repaired shall incorporate sealing methods that are capable of being renewed without damage to the container when the equipment is repaired, re-filled, and re-sealed. The container shall be marked in accordance with Clause 6, item b).
4.1.2 Pressure test of container
The electrical equipment, parts of electrical equipment or Ex components protected by powder filling “q” shall meet the pressure test requirements specified in 5.1.1.
4.1.3 Degree of protection of the container
4.1 .3DV DR Modification of Clause 4.1.3 to replace with the following:
The container of the electrical equipment, parts of electrical equipment, or Ex components protected by powder filling “q”, in their normal service condition, i.e. with all openings closed as in normal use, shall comply at least with the degree of protection 1P54 as defined in IEC 60529. If the degree of protection is 1P55 or higher, and the container is not hermetically sealed, the container shall be provided with a breathing device. The container with the breathing device in place shall comply at least with the degree of protection 1P54 according to IEC 60529. The test shall be conducted on an empty container without the powder filling installed. At the end of any water ingress tests, no water shall be visible inside the container.
NOTE 1 As the container may need to be destroyed in order to determine the entrance of dust or water, two separate test samples could be required for the two ingress tests.
NOTE 2 When the container is also the external enclosure, the tests of enclosures requirements of UL 60079-0 lEG 60079-0 apply.
4.1.4 Filling procedure
Filling shall be carried out so as not to leave any void within the filling material (for example by shaking down). The free space within electrical equipment, parts of electrical equipment or Ex components protected by powder filling “q” shall be effectively filled with filling material (see also 4.3.2).
4.1.5 Containers that are not external enclosures
The container of type of protection “q” equipment or Ex Component that is installed or intended to be installed internal to another enclosure is considered the same as that of an Ex Component.
4.2 Filling material
4.2.1 Material specification
The material shall be quartz or solid glass particles.
The material specification shall state that, determined in accordance with the ISO 2591-1 procedure for dry materials, the size of particles are within the following sieve sizes:
— 1 mm nominal aperture sieve in accordance with ISO 3310-1 or ISO 331 0-2
— 500 jim nominal aperture sieve in accordance with ISO 3310-1.