Programmable Logic Controller (PLC)
The PLC was invented in 1968
when General Motors sought an electronic replacement for hard-wired relays and timers that could accurately and reliably control the repetitive starts and stops of machinery. These hard-wired systems required the very time-consuming and expensive task of manually rewiring thousands of relays each year. The introduction of the PLC, and the evolution of relay logic, enabled automated control in the harshest environments while reducing the size and complexity of large relay panels.
They are still relied on in automotive manufacturing, as well as in food processing, material handling, pharmaceuticals, and many other industries. PLCs have evolved to accommodate the very sophisticated control strategies manufacturing machines now require; hence very sophisticated software solutions are required within the PLC. A PLC can be programmed via multiple programming languages familiar to software engineers. This level of sophistication makes PLC systems inherently expensive; furthermore, one incorrectly programmed PLC can cause plant downtime or create a dangerous condition.
Lighting Control Systems
Lighting Control Systems evolved out of light controllers and have always been about turning on and turning off the lights. This singleness of purpose has led to controllers that are highly evolved. They are widely used on both indoor and outdoor lighting of commercial, industrial, and residential spaces to maximize energy efficiency, improve occupant comfort, satisfy building codes, or comply with green building goals.
Having been born in the building control environment, lighting control systems have an easy time interfacing with other building systems and benefit from the familiarity that installers, designers, and users have with these and similar systems. They can be accessed remotely through a computer or smart device. This empowers building managers with a complete, holistic view into the building’s operational status, energy consumption, and utilization.
They are capable of sophisticated control scenarios that adapt to environmental and human factors in real time, such as dimming and granular management by cubical, section, floors, or entire building. This level of sophisticated control has led to systems that can be easily commissioned on startup and easily modified over time.