Kenneth L Wester

US Patent:

6738441, May 18, 2004

Filed:

Jul 5, 2000

Appl. No.:

09/609354

Inventors:

Steve R. Webster - Raymond NH
Richard H. Breinlinger - Hampstead NH
Kenneth L. Wester - Nashua NH

Assignee:

Schneider Automation Inc. - North Andover MA

International Classification:

H04B 100

US Classification:

375350, 375257

Abstract:

A method and device for filtering an input signal received by an input module in order to produce a filtered input signal, wherein the received input signal is converted such that it has either a HIGH input state or a LOW input state each having a time duration characteristic of the input module, and the filtered input signal is represented by an ON filtered state and an OFF filtered state. The time duration of the HIGH input state and the LOW input state are determined by sampling the converted input signal at a certain sampling rate so as to allow the sampling results to be used by a filtering algorithm to set the filtered input state to ON or OFF based on a set of filter parameters which may vary from one input module to another. The filtering device is adapted to be configurable such that the filter parameters can be electronically selected so that the same filtering algorithm can be used for different input modules having different electrical characteristics.