Patent ID: 6154683
Filing Date: 2000-11-28
Classification: G05B,Y02B,Y04S

Abstract:
An industrial controller for use in hazardous environments and configured to read inputs from an industrial process and provide outputs to the industrial process under the direction of a stored control program, the industrial controller comprising:a power supply limited in output to avoid the generation of sparks with sufficient energy to ignite a flammable atmosphere during a fault condition in the power supply;a serial network port receiving and transmitting data over serial network media using signals limited in power to avoid the generation of sparks with sufficient energy to ignite a flammable atmosphere during a fault condition of the serial network;a processor executing the stored program and communicating with the serial network and receiving power from the power supply;a plurality of interface circuits receiving power from the power supply and communicating electrical signals over interface lines between the industrial controller and the industrial process, the electrical signals limited in power to avoid the generation of sparks with sufficient energy to ignite a flammable atmosphere during a fault condition of the interface lines; anddigital circuitry receiving power from the power supply and communicating data between the serial network port and at least one of the interface circuits;whereby the industrial controller may be operated from a location wholly within a hazardous location.