2909B.5

Description

HPS 2A and 3A motor starting autotransformers have been an industry standard for many years. Autotransformers are a significant component of a motor controller. In its simplest form, motor starters start and stop a motor and protect against overvoltage and under voltage. In most applications, a simple full-voltage magnetic starter places full voltage across the motor’s windings on startup and maintains full voltage at the motor during the run mode. For larger motors, or motors where the load is connected, the effect of motor-starting inrush can stress the electrical system with significantly lower currents in the distribution network. This can cause all manner of disruption to the system with subsequent interruption in the facility. In these cases, reduced-voltage starting must be applied. The addition of a motor starting autotransformer during the startup sequence limits the starting inrush current. The 2A and 3A product line is designed for Medium Duty service including applications for drive loads such as pumps, compressors, conveyers and fans. Units are manufactured in accordance with NEMA Industrial Controls and Systems, Publication No. ICS-1970.