Heavy Truck
Electra-Finish, Inc. Painting of Volvo MD11 & MD13 Valve Covers www.electra-finish.com
Introduction to Plc and Scada
Introduction to PLC’s
Programmable Logic Controllers
Bedford Associates, founded by Richard Morley introduced the first Programmable Logic Controller in 1968. This PLC was known as the Modular Digital Controller from which the MODICON company derived its name. The History of the PLC as told to Howard Hendricks by Dick Morley provides an interesting insight into the early development of the PLC.
 Schnieder Quantum PLC
Programmable Logic Controllers were developed to provide a replacement for large relay based control panels. These systems were inflexible requiring major rewiring or replacement whenever the control sequence was to be changed.
The development of the micro processor from the mid 1970’s have allowed Programmable Logic Controllers to take on more complex tasks and larger functions as the speed of the processor increased.
Ladder Logic
PLC had to be maintainable by technicians and electrical personnel. To support this the programming language of Ladder Logic was developed. Ladder Logic is based on the relay and contact symbols technicians were used to through wiring diagrams of electrical control panels.
Until recently there has been no formal programming standard for PLC’s. The introduction of the IEC 61131 Standard in 1998 provides a more formal approach to coding. PLC Manufacturers have so far been slow on the uptake of the standard with partial implementation. The SearchEng articleIEC 61131-3, a Standard for PLC Software by R.W. Lewis provides an introduction to the standard.
The documentation for early PLC Programs was either non existent or very poor, just providing simple addressing and basic comments, making large programs difficult to follow. This has been greatly improved with the development of PLC Programming Packages.
SCADA and HMI
The early programmable logic controllers interfaced with the operator in much the same way as the relay control panel, via push-buttons and switches for control and lamps for indication.
...honda steed Directory
Heavy truck painting and body work. Tandem Truck Sales also offers an ... If you would like to further discuss truck painting or body work with us: ...
is equipped to sandblast and paint all makes and models of dump trailers, dump truck body's, heavy equipment and more. Sandblasting & Painting Services ...
Get directions, reviews, payment information on Cliffs Heavy Truck Painting located at Whitefield, ME. Search for other Automobile Body Repairing & Painting in Whitefield
Cliffs Heavy Truck Painting, Whitefield, ME : Reviews and maps - Yahoo! Local, 207.549.7146. Get Ratings, Reviews, Photos and more on Yahoo! Local.
Based on BBB files, Kearney's Painting has a BBB Rating of A+ on a scale from A+ ... Truck & Heavy Equipment Repair & Parts, Truck Painting & Lettering ...
