Filter membrane Rittal 3321.705 for enclosure ventilation, replacement filter media (pack quantity not specified)

The Rittal 3321.705 filter membrane is a chopped-fibre mat designed for enclosure ventilation and air filtration in electronic and electrical cabinets. It features a progressive structure with an open side for dust-laden air and a closed side for clean air, offering reliable filtering of most dust particles from around 10 µm. The material is temperature-resistant up to 100°C and meets self-extinguishing category F1 according to DIN 53 438.

Advantages

The progressive chopped-fibre construction provides effective capture of particles while maintaining airflow. The dual-sided design—with an open structure facing the dust-laden air and a closed structure on the clean-air side—helps prolong service life and simplifies installation orientation. Temperature resistance to 100°C and F1 self-extinguishing classification increase safety in electrical enclosures.

Suitable for

• Ventilation and filtration panels in electrical and electronic enclosures
• Replacement filters for Rittal SK series and similar cabinet filter housings
• Applications requiring removal of dust from approximately 10 µm and larger particles

When it may not be suitable

This filter membrane is not intended for capturing submicron particles or for HEPA-level filtration; it is designed for coarse to medium dust filtration starting at about 10 µm. It may not be appropriate where oil mist, sticky contaminants, or chemical vapours are present without additional specialized filtration.

Key specifications

• Material: chopped-fibre mat with progressive structure
• Particle retention: effective from approximately 10 µm
• Temperature resistance: up to 100°C
• Fire behaviour: self-extinguishing category F1 (DIN 53 438)
• Structure: open side for dust-laden air, closed side for clean air

How to use

Install the filter membrane in the filter frame or housing with the open-structure side facing the incoming, dust-laden airflow and the closed-structure side facing the enclosure interior. Replace the membrane according to the equipment manufacturer’s maintenance intervals or whenever pressure drop increases noticeably. Ensure correct seating and sealing to prevent bypassing of unfiltered air.

What to consider before purchase

• Confirm compatibility with the filter frame or holder dimensions and the specific Rittal SK model if replacing original parts
• Assess required particle retention: this membrane is intended for coarse/medium dust from ≈10 µm, not for HEPA-level filtration
• Consider environmental factors such as oil, chemical vapours, or moisture that may require specialised media

Usage recommendations

For correct performance, orient the membrane with the open side toward incoming air, perform regular inspections for clogging, and replace when airflow is substantially reduced or after recommended service intervals.