(19)

(11)

EP 0 572 639 A1

(12)

(43) Date of publication: 08.12.1993 Bulletin 1993/49 (21) Application number: 93901933.0 (22) Date of filing: 18.12.1992

(51) International Patent Classification (IPC):  H04M 11/ 00( . ) H04N 5/ 765( . ) H04B 1/ 20( . ) (86) International application number: PCT/US1992/011119 (87) International publication number: WO 1993/013630 (08.07.1993 Gazette 1993/16)

(84) Designated Contracting States: FR GB (30) Priority: 20.12.1991 US 19910811780 (71) Applicant: SQUARE D COMPANY Palatine, IL 60067 (US)	(72) Inventors: STEVENSON, Bruce Lexington, KY 40504 (US) FARINELLI, Robert Lexington, KY 40515 (US) UNSELD, Bill, R. Lexington, KY 40517 (US) ROSE, Shelton Lexington, KY 40514 (US) DICKENS, James Lexington, KY 40503 (US) (74) Representative: Sorrell, Terence Gordon  Fitzpatricks, Cardinal Court, 23, Thomas More Street London E1 9YY London E1 9YY (GB)