05512732 is referenced by 272 patents and cites 23 patents.

A parallel, zone-type heating cable wherein thermally-controlled ferrite reed switches in each zone regulate current flow to heating elements aligned in parallel with each other. Two parallel conductors deliver current to the switches and the heating elements. A dielectric insulation material separates the conductors from each other and the heating elements. The heating cable may further include a component having a particular temperature coefficient of resistance aligned in parallel with the switch to further regulate current flow to a positive but lesser level when the switch is open.

Title
Switch controlled, zone-type heating cable and method
Application Number
586441
Publication Number
5512732
Application Date
January 7, 1993
Publication Date
April 30, 1996
Inventor
Blake E Heimbecker
Schertz
TX, US
Chandrakant M Yagnik
Austin
TX, US
Agent
Pravel Hewitt Kimball & Krieger
Assignee
Thermon Manufacturing Company
TX, US
IPC
H01C 7/02
H05B 1/02
H05B 3/34
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