BuyLog Flippingbook MAR 2024

TRANSFORMERS - LOW VOLTAGE, DRY TYPE, BUYLOG SECTION 5

5-44

— Drive isolation Product overview

The use of thyristor control circuitry with adjustable-speed drives has resulted in a need for a line of isolation transformers specifically designed to meet the demanding power supply requirements of thyristor controlled drives. Symmetrically placed taps and added coil bracing minimize mechanical forces caused by the often severe thyristor drive duty cycles. These reinforcing features also help protect the transformer from the regenerative duty cycles and more frequent temporary short-circuits associated with thyristor drives. Isolation transformers also reduce line pollution feedback resulting from thyristor firing circuits. The ABB delta-wye designs meet the NEC requirements for grounded secondary neutrals that isolate primary distribution systems. kVA ratings of the DIT line cover most dc motor requirements from 3 to 1000 hp.

The enclosed drive isolation transformers are UL listed and are excluded from the DOE 2016 regulations. Features • Unique core and coil design using grain oriented silicon steel • Core and coil assemblies mounted on rubber isolation pads • Single piece front/back • Copper ground strap

— Drive isolation