Star Delta Motor Control Panel

Large motors almost never get the benefit of a light start. When they are started directly, they will draw a very heavy inrush current and create severe disturbance across the totality of the bus. By utilizing our star delta motor control panels, we can manage this transition in a controlled and repeatable manner with timing based on the acceleration of the motor and its load inertia. The timings for changeover are not based on fixed timer values taken from jobs done previously.

These panels are manufactured for pumps, compressors, blowers, and conveyor drives that require reduced starting currents but do not want to add drive electronics to accomplish that goal. The contractor selection, thermals overload settings, and short-circuit protection settings are matched with the actual FLC and duty cycle of the motor. There is mechanical and electrical interlocking between the star and delta contactors to prevent any overlap in timing during the transition process.

The arrangement within an enclosure keeps shortening and rigidity of power connections thus allowing for large inrush currents while assuring that no rise in temperature occurs at the joints. Control wiring is run separately from all other wiring and will ensure stable operation of timers, as well as provide for ease of tracing faults in wiring.

The tests performed during the manufacturing process include checking each unit for proper performance of the star to delta transfer, current characteristics, proper function of interlocks, and the actuation of overload protection devices. These types of star delta motor control panels have been manufactured in anticipation that they will operate effectively in facilities throughout the United States and will provide for dependable motor starting, minimum impact to the power system, and simple access to perform maintenance in an industrial setting on a continuous basis.