Delfin CUBE 20 K2 PN Z22

The two models have identical mechanical and filtration specifications -- same motor, same airflow (2,500 m³/h), same vacuum (21 mbar), same cartridge filter surface (200,000 cm²), same container (90 L). The difference is certification and construction for explosion hazard. The Z22 version is ATEX-certified for Zone 22 (II 3D Ex h IIIC) and can be used in officially classified zone areas; the ACD version is for non-classified areas with combustible dust (IEC 60335-2-69 Annex AA). The Z22 model has additional dust-tight testing of the entire enclosure, Ex-certified motor and control box, plus nameplate and documentation per the ATEX directive 2014/34/EU. The price difference reflects this extra certification effort (ca. 2,500-3,500 EUR over the ACD version).

There is a subtle but important difference. The ACD version uses an 'automatic alternating air washing system' -- pulse-jet fires in a rotating pattern while the unit runs normally. The Z22 version is specified with 'automatic filter cleaning with operated air during suction' -- same fundamental principle, but ATEX-compatibly timed so compressed-air pulses are coordinated with suction-point vacuum to avoid momentary counter-flow particles on the cartridge's clean side. For the end-user it makes no difference -- cleaning is still automatic, still continuous and still operationally independent of the operator. But the certificate requires this coordinated design to maintain dust-tight certification during pulses.

The AISI 304 stainless steel control box is an ATEX construction standard on Z22 models -- required by the aggressive environmental norm for Zone 22, where the atmosphere may contain corrosive substances beyond combustible dust. The stainless box withstands condensation, chemical attack from process dust (e.g. alkaline powders or corrosive organic compounds), and mechanical impact in industrial environments. The box is IP65 enclosed, which combined with the deduster's own IP65 ensures the electrical system is sealed against dust and water jets. Contactors, cables, signal circuits and control cards are all Ex-certified and installed per ATEX guidelines.

The CUBE 20 K2 PN Z22 is self-certified by Delfin per the harmonised standard EN 17348:2022 (harmonised March 2023). 'Self-certified' means that Delfin as manufacturer has performed the required performance tests per the standard's annexes and issued the CE conformity declaration; it is NOT certified by a notified third party. For Category 3D products (Zone 22) the ATEX directive 2014/34/EU permits the manufacturer's own conformity assessment under certain conditions -- this applies specifically to this category. Documentation (CE declaration, EC type examination report where relevant, and controlled production procedure) is available on request. If your safety organisation requires notified third-party certification, you should consider asking for documentation or upgrading to a Category 2D model.

ATEX installations in Zone 22 require all conductive parts in contact with dust to be connected to the same earth potential -- maximum resistance 10⁸ ohm. For the CUBE 20 K2 PN Z22 this applies to the deduster chassis, filter housing, container, suction piping, and all extraction arms or Y-branches coupled to it. Delfin supplies the model with a standard earth grounding clamp on the chassis (MT included), but installation must verify continuity between ALL components. At the transition from metal hose to antistatic polymer hose, a metallic end clamp with sufficiently low resistance is required -- typically a stainless steel ring clamp. During installation, measure: (1) from each collection point to earth (≤10⁸ ohm), (2) from container to chassis (continuity), and (3) from chassis to the installation's earth busbar.

Classic ATEX Zone 22 industries for this model are (1) pharmaceutical production with active powder substances classified as combustible (e.g. paracetamol, lactose or protein powders), where strict filter quality and continuous operation is required, (2) food and flour industry with higher risk classification than average -- especially where milling and sieving generate dust in constant presence, (3) chemical industry with pigments and colourants (carbon black, organic pigments), (4) coating and powder coating halls with fully classified zones due to concentration of combustible powder, and (5) light-metal processing with aluminium or magnesium powder in classified production cells -- though here the INERT version of the deduster might be a better choice due to reactive metallic dust. Documented risk analysis is always the precondition.