A LITTLE HISTORY

Over the last 20 years, the complexity and sensitivity of electrical distribution systems have changed and grown substantially. Electronic equipment, such as industrial PLCs, robotics, computers, and office equipment, use sensitive and critical microprocessors (chips). In addition, industrial and commercial facilities are powering energy efficient solid state lighting, energy management systems, telecommunications, building support systems, air handling, fire alarm and security systems, HVAC systems, drives, and more. In all modern power systems, there are interactions of the electrical equipment throughout a facility. In years past, these interactions had little consequence. Motors, incandescent lighting, relays, and resistive heating elements all used power in essentially the same way with little apparent effect on each other.