Description

The ABB PSR85 is the largest model in the PSR series, rated at 85 A for three-phase induction motors up to 45 kW at 400 V, providing electronically controlled voltage ramp starting for large industrial motor applications. The PSR85 covers the 45 kW motor size used in large pumps, fans, compressors, and heavy industrial drives where the high starting currents and mechanical shocks of across-the-line starting would damage equipment, stress the supply network, or cause unacceptable mechanical disturbance to the driven load. Its thyristor-based voltage control provides smooth, adjustable acceleration ramps for optimised starting performance.

Compliant with IEC 60947-4-2, the PSR85 is designed for 35 mm DIN rail mounting and features the same simple two-parameter (initial voltage and ramp time) adjustment system as other PSR models, making commissioning straightforward for field engineers. A bypass contactor is required in parallel for continuous operation, and ABB provides co-ordination tables for selecting appropriate AF-Line bypass contactors, fuses, and protection devices for complete motor starter assembly design around the PSR85.

The PSR85 is applied in large water treatment pump drives, industrial process fans, heavy compressor starters, large conveyor drives, and significant process machinery in manufacturing, mining, water and wastewater, and energy production facilities. For motor applications above 45 kW, ABB’s PSS and PSTX series soft starters provide higher current capability with enhanced features. The PSR85 represents the upper capacity of the simple PSR series, offering proven soft start performance for applications where the benefits of current limitation and smooth acceleration are required for motors in the important 37–45 kW range.