System for disabling the reset circuit of fault indicating means

• US 4,034,360 A
• Filed: 08/06/1976
• Issued: 07/05/1977
• Est. Priority Date: 08/06/1976
• Status: Expired due to Term

• Current Assignee: Edmund O. Schweitzer Jr
• Original Assignee: Edmund O. Schweitzer Jr
• Inventors: Schweitzer, Edmund O. Jr.
• Primary Examiner(s): Habecker, Thomas B.
• Application Number:
  US05/712,281
• Time in Patent Office: 333 Days
• Field of Search: 340/253 A, 324/133
• US Class Current: 340/502
• CPC Class Codes: G01R 19/145 Indicating the presence of current or voltage
• CPC Class Codes: G01R 19/16509 using electromagnetic relays, e.g. reed relay magnetically driven reeds G01R9/06

Abstract

The reset circuit of a fault indicator is disabled to prevent automatic restoration of the movable target from fault indicating position where it can be observed and manually rest. A manually operable switch is connected across the reset ciruit and its contacts are closed by permanent magnet means or by manually operable switch means.

Claims

1. Fault indicating means responsive to flow of fault current in an electrical distribution system comprising:

indicator means movable from one position to another position on flow of fault current in said system, a trip circuit responsive to flow of fault current in said system to shift said indicator means from said one position to said other position, a reset circuit to shift said indicator means automatically back to said one position on restoration of said system to normal operating condition; and

manually operable means for disabling said reset circuit to maintain said indicator means in said one position.

2. Fault indicating means according to claim 1 wherein said disabling means includes switch means connected across a portion of said reset circuit.

3. Fault indicating means according to claim 2 wherein said switch means includes magnetically operable contacts, and means generating a magnetic field is juxtaposed to said switch means to close said contacts.

4. Fault indicating means according to claim 2 wherein a permanent magnet is movably mounted adjacent said switch means and is arranged in one position to close said contacts and in another position to open said contacts.

5. Fault indicating means according to claim 4 wherein said permanent magnet is pivoted intermediate its ends.

6. Fault indicating means according to claim 4 wherein said permanent magnet is pivoted at one end.

7. Fault indicating means according to claim 2 wherein said switch means includes:

normally open contact means, and manually operable means for closing said contact means.

8. Fault indicating means according to claim 7 wherein over-center toggle means cooperates with said manually operable means for closing said contact means.