Afocus on size has led to the latest in AC drives from ABB Inc., New Berlin, Wis. The company recently introduced the ACS 800 low-voltage drives, which are 50% smaller than their equivalent predecessors.
Available in NEMA 1 or NEMA 12 enclosures, the bookshelf-style units range from 6.5-in. wide, low-hp designs up to freestanding 600-hp units that measure 13.78 in. The freestanding enclosures of the 150 to 600-hp drives easily turn to fit into deep, narrow spaces or wide, shallow spaces.
Designed with integral EMC filters and chokes and rated at supply voltages of 230 V to 690 V, the ACS 800 drives are backward compatible with ABB's previous ACS 600 family. Parameters have the same name and scaling.
The new drives include ABB's proprietary open-loop direct-torque control technology, which eliminates the need for installing encoders and lets the drives calculate the state (torque and flux) of the motor 40 times/sec, making the motor controllers trip-less.
Also built into the new series is adaptive programming, which eliminates the need for extra hardware or software and extends the freely programmable I/O and parameter selections. Adaptive programming consists of a set of 15 programmable blocks for performing any operation from a predefined set of 20 functions. All common mathematical and logical functions as well as switches, comparators, filters, and timers are available for detailed programming.