Cleanroom contamination control continues to provide improved performance at ever reduced prices. The use of fan filter units (FFUs) continues to gain market share over centralized systems as their performance is improved while installed costs are driven lower, eliminating the key obstacle of a higher installed cost. The expansion of smaller clean-air space, special areas within ballroom clean-spaces, and mini-environments has created new challenges to the application of FFUs in a “set-it-and-forget-it” environment. This article focuses on the electronics and motor/fan choices for the FFU that influence “smart FFU” options. Improvements in filter media, noise reduction efforts, and other developments have been well documented, providing greater price/performance in FFU selection and allowing suppliers to “differentiate” their solutions from the competition. The information below reviews the present options and new “smart FFU” options. These options will create a new baseline of price/performance not previously seen in the market today. As the FFUs continue to capture more market share from centralized systems, the new, smarter FFU options will increase the “smart cleanroom” share of this growing, clean-space market segment.

EXISTING “SMART” SOLUTIONS – EC BASED
“ Smart FFU” product sales have been steadily growing in the market. The introduction of the MAC10 IQ in 2001 (Figure 1) by ENVIRCO using the GE-ECM (electronically commutated motor) platform to provide control to the FFU was a major leap forward from the basic AC fan solutions prevalent at the time. Today, smart ECM solutions are available from many vendors as they have incorporated the GE-ECM platform as well or used EC fans from other suppliers. The market has become large enoughto attract companies creating their own, proprietary EC solutions.

The market acceptance of EC-based FFU solutions have been influenced by: positive attributes; smart EC-based solutions operating at lower power levels and running quieter than AC products and products with addressable, controlled I/O along with failure notification and self-correction software. Negative attributes are high cost, inverter drive complexity and reliability concerns, potential RFI concerns, customized software platforms, etc. that require system integrators, expensive commissioning, and high “installed cost.” A driving factor is that the clean-air market segment is a small part of the greater HVACR market. The majority of products and solutions used by cleanroom manufacturers has been created for the broader HVACR market rather than the targeted. The market is then divided into the “haves” (smart EC based systems that are custom designed and installed) versus the “have-nots” (basic AC systems that are set-and-forget). The heavy cost difference (a factor of 2 to 3 times in installed cost) between these options polarized the market intothese two extremes.

This two-tier system has been in place for over five years with product differentiation emphasis targeting noise, maintenance considerations, and service and energy consumption as key pivotal points in choosing the right system solution. The market continues to look at innovative ways to close the “gap” between the low cost AC platform and its EC counterparts. Several companies developed their own platforms and solutions to try and address the “gap” aswell. An example is shown in Figure 2.

It is this increased effort that has begun to change the landscape for “smart FFU” solutions in thecleanrooms market. Development and improvements are accelerating as performanceconverges and competitive price pressures demand improved-cost platforms.