Timing the announcement with the AHR show this week in Chicago, Danfoss has introduced the VLT® HVAC Basic Drive - a small, full-featured variable speed drive that promises reliable, low-cost HVAC performance for basic fan and pump operations.
“In some fan and pump operations advanced drive features are unnecessary and, because they are superfluous, simply add to overall costs. The VLT HVAC Basic Drive is an ideal solution that strikes the optimum balance between price and variable speed drive performance in these straightforward HVAC installations,” says Ed Smith, a company representative.
VLT HVAC Basic Drives minimize wear on HVAC equipment and maximize system up-time, while reducing HVAC system operating costs up to 15%.
The company says that the VLT HVAC Basic Drive is the most compact drive in its class and with its specifications to reduce panel space requirements. Numerous built-in features reduce, and in some applications may even eliminate, the need for additional external equipment such as gateways, PI controllers and PLCs. An Automatic Energy Optimizer function reduces energy consumption by up to 15%, while “sleep mode” functionality can help further reduce operating costs and extend drive life. Bypass frequencies minimize operating noise, vibration and resonance issues.
VLT HVAC Basic Drives also feature a “start up wizard” that makes drive set-up fast and simple, and easy tool access further aids fast and effective commissioning and operation. A robust single-piece enclosure provides reliable, maintenance-free operation in ambient temperatures up to 50 degrees C, with no external cooling required. A unique cooling concept provides problem-free performance, even in harsh environments, without forced air flowing over the electronics.
Drives are coupled with motor systems for one of two basic reasons: 1.) affinity laws promise greater energy efficiency when full speed operation isn’t required, or 2.) something about the process demands variable operation and control. Sometimes the needs are combined and the drive, or drives, become very important elements in a machine, building, water or factory system. This article will focus on energy efficiency.
Since the drive came into view as a green technology -- a tool to lower consumption and costs associated with energy -- the economics of drives have improved. For example, since 2001, the base costs of a drive, purchased, installed and operating, are flat or slightly down, while the electricity price paid by businesses is up.

As long as these two numbers move in the directions that they have been moving, more businesses will become drive owners, whether the people in them know what a drive is or not. It would seem to be a matter of necessity.
However, as competition increases, project budgets tighten, and economic trends remain volatile, small differences in energy performance matter. More importantly, service advantages among drive suppliers can be the difference between a selecting a smart, green system to start with, or regressing to full throttle operation in the interest of stretching limited construction funds. Drives are not ubiquitous, yet. In the U.S., 84% of motors are not yet drive controlled and in the E.U., 76% of motors are not drive controlled.
To try to understand why, we asked energy consultants to explain the challenges that they face specifying drives. The top two reasons: effort to predict energy ROI, and complex or custom application work.

Interestingly, those same energy consultants tell us that they struggle to prove energy payback concretely. While it is common practice among consultants to rely on drive suppliers to offer pre-sale predictions of energy performance and payback, it is rare that an installed drive is proven, through audit or performance testing, to be delivering on its economic promise.

More than 50% of consultants say that they have no idea if their projects payback and another 20% say that the payback estimate is proxy for compliance (but it shouldn’t be.)
So we think that 2012 will be the year of the audit. Watch as suppliers visit job-sites, parametric data, calculators and kW meters in hand, to show why drives are, and will be, crucial to reducing energy consumption, costs, and to lowering carbon footprint. And watch as consultants begin to demand that such services are included by, even required of, accepted suppliers in winning contracts.
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*We interviewed more than 190 mechanical and HVAC consultants and users of DASH Energy ROI Software in North America for this data.