Electric circuit tracer

• US 20070063688A1
• Filed: 09/22/2005
• Published: 03/22/2007
• Est. Priority Date: 09/22/2005
• Status: Active Grant

• Current Assignee: Ideal Industries Incorporated
• Original Assignee: Ideal Industries Incorporated
• Inventors: Nguyen, Tich
• Granted Patent: US 8,351,869 B2
• Time in Patent Office: Days
• US Class Current: 324/67
• CPC Class Codes: G01R 31/086 in power transmission or distribution networks, i.e. with interconnected conductors

Abstract

A circuit tracer includes a transmitter that places one of first and second signals on an electrical circuit depending on whether the circuit is energized. A receiver detects the signals imposed on the circuit by the transmitter, with the signal strength indicating the proximity of the receiver to the circuit. The receiver detects which of the transmitter signals is present and thereby can also indicate whether power is present on the circuit. The receiver has first and second antennas, one optimized for wide area detection and one optimized for circuit breaker detection. The receiver has an OLED display that remains properly oriented for viewing regardless of the orientation of the receiver housing. The transmitter can have a clamp version that inductively couples to the circuit being traced.

Claims

1. A transmitter for an electrical circuit tracer, comprising:

an attachment element for electrically coupling the transmitter to the electrical circuit;

a power detection circuit connected to the attachment element;

a pulse generator connected to the power detection circuit, the pulse generator outputting a first signal if power is present in the electrical circuit and a second signal if power is not present in the electrical circuit; and

a transmission circuit connecting the pulse generator to the attachment element to place one of said signals on the electrical circuit.

2. The transmitter of claim 1 wherein the attachment element comprises one of the group consisting of probes, alligator clips and prongs.

3. The transmitter of claim 1 wherein the attachment element comprises a clamp.

4. The transmitter of claim 1 wherein the first and second signals comprise pulses having different widths.

5. A circuit tracer for locating an electrical circuit, comprising:

a transmitter having an attachment element for electrically coupling the transmitter to the electrical circuit, a power detection circuit connected to the attachment element, a pulse generator connected to the power detection circuit, the pulse generator outputting a first signal if power is present in the electrical circuit and a second signal if power is not present in the electrical circuit, and a transmission circuit connecting the pulse generator to the attachment element to place one of said signals on the electrical circuit; and

a receiver having at least one antenna for detecting said signals from the transmitter and a display responsive to the antenna for indicating the level of the signal detected.

6. The circuit tracer of claim 5 wherein the display is an OLED display.

7. The circuit tracer of claim 5 wherein the display is a seven-segment LED display.

8. The circuit tracer of claim 5 wherein the receiver further comprises an indicator responsive to the antenna for indicating which of the first and second signals was detected.

9. The circuit tracer of claim 8 wherein the indicator is an audio indicator.

10. A receiver for a circuit tracer, comprising a housing, a display mounted in the housing for visually displaying information to a user, a sensor in the housing for detecting the orientation of the housing, the display being responsive to the sensor to orient its information such that it is readable by a user.

11. A receiver for a circuit tracer, comprising:

at least one antenna for sensing signals on an electrical circuit;

a variable gain amplifier connected to the antenna;

an envelope detector to convert the sensed signal to a square wave; and

a display for indicating the magnitude of the square wave.

12. The receiver of claim 11 wherein the display further indicates the width of the square wave.

13. The receiver of claim 11 wherein the square wave is generated by a logarithmic amplifier.

14. The receiver of claim 11 further comprising a second antenna and a switch connected to the antennas for selecting a sensed signal from one of the antennas.

15. A transmitter for an electrical circuit tracer, comprising:

a housing;

a clamp attached to the housing and having a pair of jaws with conductive elements therein for electrically coupling the transmitter to the electrical circuit;

a pulse generator in the housing and capable of outputting a signal; and

a transmission circuit connecting the pulse generator to the conductive elements in the clamp to place one said signal on the electrical circuit.

16. A method of tracing an electrical circuit, comprising the steps of:

electrically coupling a transmitter to the electrical circuit;

detecting whether there is electric power available on the electric circuit;

generating a first signal if power is present in the electrical circuit and a second signal if power is not present in the electrical circuit; and

placing said first or second signal on the electrical circuit.

17. The method of claim 16 further comprising the step of detecting which of said signals is on the electrical circuit and indicating to a user which of said signals was detected.