Delfin CUBE 20 K4 PN ACD

Same logic as on the ZFR EV: the K4 is the right choice when (1) total piping length exceeds 15-20 metres, (2) the number of simultaneous collection points is 4 or above, or (3) the dust is particularly sticky, heavy or hygroscopic (moist metal dust, moist concrete dust, polymer process with adhesive binder). For ACD installations a fourth reason is added: continuous 24/7 operation over many years requires the extra motor headroom of the K4 to avoid running the motor at its limit under demanding load. The K2 is sufficient for 8-12 hours daily operation with 2-3 points; the K4 is the choice for continuous operation on central-suction architecture.

No -- the ACD version is specifically certified for non-ATEX classified areas per IEC 60335-2-69 Annex AA. If your area is classified as Zone 22 (external dust zone during normal operation), you must choose the CUBE 20 K4 PN Z22 -- the identically-equipped ATEX version. The difference is constructive and certification-wise: the Z22 version has Ex h IIIC T80°C internal / T135°C external marking, a nameplate with ATEX mark and CE documentation per the ATEX directive 2014/34/EU, plus additional tightening of cable seals and dust-tight testing. The ACD version lacks these -- and using an ACD model in a Zone 22 zone is a violation of ATEX regulations regardless of how safe the model might be in practice.

Cartridge filter life depends on three factors: dust type, dust loading and pulse-jet cleaning quality. Under typical ACD conditions (wood dust, flour dust, powder coating) and continuous 8-hour operation a cartridge life of 2-4 years is expected -- corresponding to ca. 6,000-10,000 operating hours. Sticky dust (glue, resin, moist flour dust) reduces life to 1-2 years because pulse-jet pulses cannot shake the layer fully off. Continuous 24/7 operation reduces calendar life but not operating-hour life -- cleaning cycles wear less than static loading. Indication of filter replacement: falling suction-point vacuum even after pulse-jet cleaning (typically below 15 mbar at nominal operation) and visible dust pass-through to the HEPA H14 final filter. Filter replacement takes 30-60 min and requires no special tools.

The HEPA H14 final filter is a 'fire-and-forget' component -- it is NOT cleaned during operation, because the filter medium is too fine and fragile for pulse-jet flushing. The design philosophy is that cartridge filters retain 99.9 % of dust, so the HEPA filter receives only a small residual fraction that accumulates slowly. In practice this means the HEPA filter typically lasts 4-8 years under normal operation without replacement, provided the cartridge filters are maintained correctly. Signs that the HEPA filter needs replacement: total suction-point vacuum drops even with new cartridges, or the built-in differential pressure sensor reports high pressure drop across the HEPA cell. Replacement requires access to the filter housing and may cost 200-400 EUR depending on supplier.

The forklift lifting points are designed to move the empty unit (250 kg) or the unit with an empty container. They are NOT dimensioned to carry a fully loaded container of up to 180-200 kg (with heavy metal dust) on top of the 250 kg chassis. If you need to move the unit during operation, the container must be emptied first. Forklift specification: 2 forklift lifting points in the chassis bottom with standard 600 mm forklift tine entry; lifting points are welded to the chassis frame and can carry the unit's full weight. In practice the lifting points are used mostly for (1) initial installation from delivery truck to final position, (2) moving to a technical service area for major renovation, and (3) scrapping at end of life. For continuous use the unit is built to stand fixed.

Calculate with three main items at 8-hours x 220 days/year = 1,760 operating hours. (1) Electricity: 4 kW nominal, ca. 3.2 kWh/h average (80 % load) = 5,632 kWh/year, at 1.5 DKK/kWh = 8,450 DKK/year. (2) Compressed air for pulse-jet: ca. 100 nl/min average = 10,560 m³/year compressed air, at typical industrial cost 0.02 EUR/m³ = ca. 1,580 DKK/year. (3) Maintenance: HEPA final filter every 5-8 years (ca. 3,000 DKK/unit / 6 years = 500 DKK/year), cartridge filters every 2-4 years (ca. 4,000 DKK/set / 3 years = 1,333 DKK/year), misc. (gaskets, valve service) ca. 500 DKK/year. Total TCO ca. 12,000-13,000 DKK/year excluding container emptying and service labour. Under 24/7 operation electricity cost rises to ca. 20,000 DKK/year; total ca. 25,000 DKK/year.