WR (Weather Resistant) Filters

The UAF WR (Weather Resistant) Filter solution utilizes a high efficiency primary filter in combination with a cleanable pre-filter.  Each filter uses a urethane gasket to provide a watertight seal.  A cleanable/ replaceable foam pre-filter assembly is installed upstream of the primary filter.  This 2-stage filtration solution offers a high-level of protection for outdoor enclosures by allowing higher air flow and lower initial resistance compared to other outdoor enclosure filter solutions.  The WR Filter solution provides protection against dust, water, and salt fog ingress to meet stringent industry standards, IP54 and Telcordia NEBS GR-487 (salt fog).  It offers similar water ingress and salt fog protection as other filters employing membrane technology, but at less cost and up to 25% lower initial resistance.  Model WR Filters meet industry compliance standards for RoHS/REACH and UL flammability.  The WR Filter can be custom designed to fit the unique enclosure characteristics and the environment of deployment by one of UAF’s protection specialists/engineers. 

Extruded Channel Frame: +/- 0.06″ length & width, +/- 0.03″ thickness

The WR pre-filter utilizes a 2-stage approach, consisting of an open-cell polyurethane foam filter media and an engineered polyester (PET) mesh.  The foam media is installed on the upstream side of the pre-filter and provides a low resistance means of capturing coarse dust particles while effectively decreasing the force of strong water jets directed at the filter.  The PET mesh is installed on the downstream side of the pre-filter and is PTFE coated for moisture resistance.  The WR primary filter provides a third stage of protection using a pleated, synthetic, MERV 15 media sealed in an aluminum frame to provide protection from fine dust particles and small amounts of water that may pass through the pre-filter.  This combination of media solutions provides an exceptional level of equipment protection for direct air cooled or convection vented outdoor enclosures.  Ratings as high as IP54 are achievable without the use of louvers, dependent upon your cabinet design.

The WR (Weather Resistant) Filter solution uses an aluminum frame for both the pre-filter and primary, both available with water sealing closed-cell foam gaskets.  A RoHS compliant chemical conversion coating can be added for corrosion protection of aluminum materials. The Model WR Filter solution is available in nearly any width and length (up to 24” x 48”) in standard, 2” and 3” nominal thicknesses (1.63” and 2.63” actual).  Custom thicknesses are also available.  For certain applications, drain holes can be added to the pre-filter frame so water exits quickly. 

UAF WR Filter solutions can help to meet the following enclosure ratings:

IP Ratings: IP54

NEMA Ratings: NEMA 3, NEMA 3R, NEMA 3S, NEMA 4, NEMA 12

Telcordia GR-487-CORE (Salt Fog)

Compliant to UL900, RoHS, and REACH

Helps meets the following enclosure ratings:  IP54 and NEMA 4, GR-487, MIL-STD-810E (Sand and Dust)

Primary Filter: MERV 15

Pre-Filter:  91% Average Dust Arrestance (Est. MERV 7)

UAF’s WR (Weather Resistant) Filters have been tested and certified to meet IP54 without the aid of mechanical protection of any kind, including louvers, hoods, or screens in a typical outdoor enclosure implementing direct-air cooling. Several customers have exceeded IP54 ratings by adding mechanical protection to their WR filter-protected enclosures.

Learn more about IP ratings

UAF’s WR Filters have passed a 30-day salt fog test using a 5% salt fog concentration per ASTM B-117 in accordance with GR-487-CORE, Issue 5.  The WR Filter provided an 85% reduction in corrosion cause by salt fog exposure.  The aluminum frame material can be coated with a RoHS compliant chemical conversion finish for addition corrosion protection of aluminum components.