Peterbilt Motors Company, founded in 1939, is an American manufacturer of medium-and heavy-duty Class 5 through Class 8 trucks headquartered in Denton, Texas. Peterbilt operates manufacturing facilities in Denton, Texas (1980), and Sainte-Therese, ThÃ©rÃ¨se. quebec
A programmable logic controller, PLC, or programmable controller is a digital computer used for automation of typically industrial electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or light fixtures.PLCs are used in many machines, in many industries.PLCs are designed for multiple arrangements of digital and analog inputs and outputs, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact.ore recently, PLCs are programmed using application software on personal computers, which now represent the logic in graphic form instead of character symbols. The computer is connected to the PLC through Ethernet, RS-232, RS-485, or RS-422 cabling.
The program is stored in the PLC either in battery-backed-up RAM or some other non-volatile flash memory. Often, a single PLC can be programmed to replace thousands of relays. Under the IEC 61131-3 standard, PLCs can be programmed using standards-based programming languages.