HVAC consultants miss out on drive features, says ABB

"As many as 70% of building services consultants may not be using the most up to date specifications when selecting variable speed drives for their HVAC installations." James, Haigh, Senior Vice President, Drives, of ABB, said at a recent conference in London.

"As a result, they could be missing out on developments that bring lower running costs to buildings; improved safety features; and quicker installation, commissioning and start up routines, thereby saving considerable time and expense," Haigh continued.

In recent years, the technology employed in variable speed drives has improved dramatically. The size of drives, measured in volume, has decreased by some 70 to 80%, while the number of components has come down by some 60 to 70%. Thus, the mean time between failure (MTBF) of drives has increased five fold. Today the MTBF is better than 1 in 50 years.

In addition, technology has enabled the introduction of more features that are of direct benefit to the building services sector. This includes re programming drives with several HVAC specific application I/0s, such as supply and return fans, cooling tower fans and booster pumps. Connecting today's drives to a HVAC system is made easy by selecting pre defined HVAC macros or by simply connecting to one of ABB's built in fieldbus options.

Harmonics and RFI emissions are major concerns within many HVAC installations. Significant advances in technology have seen the development of DC chokes that can reduce harmonic emissions by up to 25%.

Also, many of today's drives feature built in PID controllers which allows demanding pump and fan functions without the added expense of an external controller.

The problem is that consultants do not purchase drives and are, therefore, not always targeted with the latest information by manufacturers. This is despite consultants being key influencers in the choice of drives with a need to understand the latest developments more than most.

To redress the issue, ABB has used the findings of its research and produced a guide entitled: "The HVAC drive Consultant's Checklist”

The document aims to be unbiased and starts by listing an the legislation, regulations and directives that affect the use of drives in buildings. It moves on to provide a definitive fist of all the product features that can be found in today's bespoke HVAC drives. Ibis gives a useful checklist for consultants who specify variable speed drives for HVAC installations. The benefit of each feature is also given.

Recognising the limitations of the printed document, ABB has also established a dedicated website for consultants. "The website offers the most comprehensive fist of certification, dimension drawings, technical guides and software tools ever assembled in one place and dedicated to the consultant," says Mike Carman, ABB's HVAC sales manager. "It's navigation structure follows that of the Consultant's Checklist which we believe sets a new standard for variable speed drive use in HVAC applications."

The website can be accessed by sending an email to enquiiies@gb.abb.com with the "Subject: HVAC for consultants".