I. Definition & Core Functions

1. ‌Basic Positioning‌
   As the primary filtration stage in HVAC or clean air systems, primary filters serve as "pre-filters," capturing dust particles ≥5μm to reduce the load on subsequent medium/high-efficiency filters and enhance overall system efficiency.

2. ‌Key Value Propositions‌

   • ‌Equipment Protection‌: Prevents large particles from clogging ducts and damaging fans, reducing failure rates.
   • ‌Cost Optimization‌: Intercepts ~80% of coarse contaminants, significantly extending the service life of high-efficiency filters.
   • ‌Purification Foundation‌: Improves indoor air quality and provides primary protection for controlled environments (e.g., medical, electronics).

   • II. Performance Parameters

   • ‌Filtration Efficiency‌

     • EN779 Standard: ‌G1–G4‌ (ascending efficiency), e.g., G4 captures 40%-60% of ≥2μm particles.
     • Typical interception rate for ≥5μm particles: ‌35%-95%‌ (dependent on media density/structure).

   • ‌Resistance & Airflow‌

     • ‌Initial Resistance‌: 10-50Pa (G3/G4).
     • ‌Final Resistance‌: Replace when ≤250Pa.
     • ‌Rated Airflow‌: 500–5000m³/h; scales with size (e.g., 595×595mm panel: 2400m³/h).

   • ‌Dust Capacity & Durability‌

     • ‌Dust Holding Capacity‌: 100-1000g/m²; pleated/bag > panel.
     • ‌Temperature Resistance‌: Standard: -10℃~70℃; high-temp variants: 250-300℃.

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