The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 14, 2009
Filed:
Mar. 02, 2002
Ron Naismith, N. Andover, MA (US);
Allan Tanzman, Newton Centre, MA (US);
Dean Papadopoulos, Groton, MA (US);
Andy Swales, Windham, NH (US);
Orlando P. Metcalf, North Andover, MA (US);
Ron Naismith, N. Andover, MA (US);
Allan Tanzman, Newton Centre, MA (US);
Dean Papadopoulos, Groton, MA (US);
Andy Swales, Windham, NH (US);
Orlando P. Metcalf, North Andover, MA (US);
Schneider Automation Inc., North Andover, MA (US);
Abstract
A method and apparatus for providing an active standby control system includes the steps of providing a first and second programmable logic controller (PLC), each controller having an operating state. Each controller includes a network module board operably connected to a network; a control unit, a remote I/O head; and, a hot standby module, each hot standby module is operably connected together. PLC. This method and apparatus can be used within a control system for monitoring input devices and for controlling output devices which reside on the standard communications network such as an Ethernet network, and the standard communications protocol used therein can be TCP using Modbus.