Recent motor drive introductions feature ac and dc models
Motor drive and controller products continue to come to market, with ac offerings dominating dc models. However, two recent introductions include each technology, as represented by AC Technology Corp. and British Sprint Electric Ltd., respectively. AC Tech's entry, SMVector drive, intends to set a low-cost threshold in the highly competitive variable-frequency drive (VFD) arena.
Said to be easy to use, SMVector also includes AC Tech's Electronic Programming Module (EPM)-a removable memory chip that reportedly allows users to program multiple drives in seconds.
Motor drive and controller products continue to come to market, with ac offerings dominating dc models. However, two recent introductions include each technology, as represented by AC Technology Corp . and British Sprint Electric Ltd., respectively. AC Tech's entry, SMVector drive, intends to set a low-cost threshold in the highly competitive variable-frequency drive (VFD) arena. Sprint Electric says it offers a versatile range of slim design, single-phase dc motor controllers. More about these new drive products and links to manufacturers' Web sites are given below.
SMVector drive from AC Technology, a member of the Lenze Group, counts on its price, flexibility, and up to a 20-hp output range to make an impact with users. It promises to "excel in environments where inverter technology was once considered too costly, including packaging machinery, food processing machinery, material handling/conveying systems, and HVAC systems," says the company. To meet requirements of those demanding applications, SMVector's features include four operating modes-V/Hz (open loop), enhanced V/Hz, vector speed, and torque-along with high starting torque, auto-tuning, advanced low-speed control, and dynamic speed regulation. Wide input voltage ranges from 120 V ac (single-phase) to 600 V ac (three-phase) reflect this drive product's global design.
Slimmest model in Sprint Electric's new single-phase dc motor controller family is only 35-mm (1.4 in.) wide.
Sprint Electric 's new dc motor controllers are designed for permanent magnet or shunt-wound dc motors in a space-saving, DIN-rail-mount package. Dual voltage supply and selectable AVF or tachometer feedback are included as standard features. They're offered in three styles: non-isolated, isolated one-quadrant, and isolated regenerative four-quadrant dc drives. Power ratings are in the 0.55-1.8 kW range (0.50-3 hp, equivalent) at 180 V dc supply, with current capability of 3.4, 6.8, and 12.2 A, respectively.
Non-isolated drive models 340, 680, and 1220 come with basic functions at a very competitive price, says Sprint Electric. Footprint size starts at 35 x 105 mm. Isolated drives (340i, 680i, and 1220i Series) cater to applications that need connection to other drives or auxiliary equipment.
Fully isolated models 340XRi, 680XRi and 1220XRi offer four-quadrant regenerative drive design for applications requiring fast, controlled deceleration/stopping or control of overhauling loads. Energy regeneration to the supply line (under braking conditions) is done without need for complex intermediate storage, resistive dumping, or additional power bridges, according to the company. In four-quadrant operation, torque reversal is said to be smooth or almost instantaneous, as required.
The new motor controllers are part Sprint Electric's integrated analog or digital dc motor control products, available from 0.37 to 265 kW. Based in England and founded in 1987, the company's products are distributed through Bardac Corp . in the U.S. and MDA Controls Inc . in Canada.
—Frank J. Bartos, Control Engineering, executive editor