Remote Continuity and Cable Identifier and Polarity Checker System and Method

Abstract

An electrical continuity test system with a tester and a remote probe. The tester includes circuitry for creating a pulsed current, an output for connection to a local end of a first test conductive element, to inject the pulses into the first test conductive element, an input for connection to a local end of a second test conductive element, and a visual and/or aural indication when the injected pulses are present on the second test conductive element. The remote probe includes an input for connection to a remote end of a first unidentified conductive element, an output for connection to a remote end of a second unidentified conductive element, a first visual and/or aural indication when the first unidentified conductive element is the first test conductive element, and a different visual and/or aural indication when the first unidentified conductive element is the second test conductive element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages will occur to those skilled in the art from the following description of the preferred embodiments, and the accompanying drawings, in which:

FIG. 1 is a schematic diagram of the local tester for the preferred embodiment of the invention;

FIG. 2 is a schematic diagram of the remote probe for the preferred embodiment of the invention;

FIG. 3 is a view of the preferred embodiment in place during a continuity test; and

FIG. 4 is a view of the preferred embodiment in place during a test that identifies cables.

DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION

The preferred embodiment includes a two-lead tester 10, FIG. 1, that injects repetitive dc current pulses into one conductive test element (such as a wire or other conductor) to which it is connected, and then detects return pulses on a second conductive test element to which it is connected. See the FIG. 1 schematic, in which the various components are labeled with identifying values and other information known to those skilled in the art. Tester 10 has output 12 to which a lead is connected for connection to a wire or other conductor. The return lead is connected to input 14. Tester 10 is powered by a 9-volt battery, not shown. LED 24 indicates that the tester is on. Timer 20 provides a series of rapid current pulses to output 12. If these pulses return through input 14, the current flow through opto-isolator 22 causes red LED 16 to flash and buzzer or tone generator 18 to sound. This indicates continuity. It would be possible to have only one annunciator rather than the two described herein.

The preferred embodiment further includes a two-lead remote probe 30, FIG. 2, that is used when the user cannot see or hear the tester. Probe 30 includes a bi-directional bi-color (red and green in the preferred embodiment) LED 32 that lights up when pulses are detected, one color for flow in one direction and the other color for flow in the opposite direction. The embodiment can be used for local or remote identification of wires or cables. FIG. 3 shows both tester 10 and probe 30 connected to wires 51 and 53 of three-wire cable 50 under test. Leads 40 connect tester 10 to cable 50, and leads 34 and 36 connect probe 30 to cable 50.

Local Testing

The inventive cable/wire identifier positively tests the electrical continuity of any two conductors within a non-powered cable (no voltage present), and thereby can be used to identify an un-marked cable out of a group of cables/wires. The tester works by injecting repetitive dc current pulses into one of the wires of a two-wire cable, in which the two wires are connected together at the remote end (either by the probe portion of the invention or by any other means). The tester then detects the return pulses from the second wire. A bright flashing LED and audible tone on the tester signals the user that continuity has been found. This is all that is required when identifying/checking wires or cables for local use; in this case, “local” means that the user is in the area of the tested circuit and can see or hear the tester unit when continuity has been made.

Remote Continuity, Polarity and Identification of Wires or Cables:

When attempting to identify wires or cables that leave the immediate area, where the user cannot see or hear the continuity confirmation light or buzzer being generated by the tester described above, the user can employ the remote probe of the invention. When this probe is connected to the far end of the wires or cables under test as shown in FIGS. 3 and 4, the remote probe's LED flashes either red or green, indicating continuity.

Operation:

The tester has two leads with alligator clips. In the embodiment the leads are red and black. The tester injects current into one wire. The tester flashes red when in use and continuity is detected.

The remote probe is connected to two wires at the remote end. If the current pulses are flowing through the wires to which the remote probe is connected, it will flash one of two colors, depending on the direction of current flow. In the embodiment, flashing green means that the tester and probe are connected with the same polarity, while flashing red indicates that the polarity is reversed. The flashing thus not only indicates continuity of these two wires or cables but also shows the polarity or identity of each. This added information is used to label each of the two cables under test. For example, if the remote probe is flashing green, label both ends of the cable under test according to the numbers or color on the clip leads of the tester and the remote probe. If the remote probe flashes red, label the remote end of the tested wires opposite of the remote probe clip lead numbers and color.

The polarity and continuity of three conductive elements such as wires or cable can be determined. See FIGS. 3 and 4. The tester is connected to two of the conductors. Thus, one of the three will not have current running through it. The remote probe will flash when connected to the two energized conductors, but will not flash when the third conductor is one of the pair to which the probe is connected. By alternating the connection of the probe, all three conductors can be identified.

Three cables can also be identified in a similar manner. See FIG. 4. By connecting the tester 10 to a wire of two different cables 71 and 72 as shown, the probe 30 can be used to identify those cables at the far end of the cable run. If there are three cables, the third cable 73 is also identified, as it is not involved in the successful continuity test.

The invention is not limited to any particular visual and/or aural annunciating device or methodology, in either the tester or the probe. For example, the probe could have two separate LEDs rather than a single bi-directional LED. Or, the probe could have one visual and one aural indicator. Or, the probe and/or the tester could have two aural annunciators with different sounds, such as a continuous and a discontinuous tone.

Although features of this invention are shown in some drawings and not others, this is not a limitation of the invention. Also, other embodiments would be apparent to those skilled in the art from the previous description and the following claims.

Claims

1. An electrical continuity test system, comprising: a) a tester, comprising: circuitry for creating a pulsed current;an output for connection to a local end of a first test conductive element, to inject the current pulses into the first test conductive element;an input for connection to a local end of a second test conductive element; anda visual and/or aural indication when the injected pulses are present on the second test conductive element; andb) a remote probe, comprising: an input for connection to a remote end of a first unidentified conductive element;an output for connection to a remote end of a second unidentified conductive element;a first visual and/or aural indication when the first unidentified conductive element is the first test conductive element; anda different visual and/or aural indication when the first unidentified conductive element is the second test conductive element.

2. The system of claim 1 in which the tester includes both visual and aural indication.

3. The tester of claim 1 in which the tester includes an opto-isolator that is electrically connected to the tester input and enables the visual and/or aural indication.

4. The tester of claim 1 in which the circuitry comprises a timer integrated circuit.

5. The system of claim 1 in which the remote probe first visual and/or aural indication comprises one color of a two-color LED.

6. The system of claim 5 in which the remote probe second visual and/or aural indication comprises the second color of the two-color LED.

7. A method of accomplishing an electrical continuity test system using a tester that creates a pulsed current and has an output for connection to a local end of a first test conductive element, to inject the current pulses into the first test conductive element, an input for connection to a local end of a second test conductive element, and a visual and/or aural indication when the injected pulses are present on the second test conductive element, and further using a remote probe comprising an input for connection to a remote end of a first unidentified conductive element, an output for connection to a remote end of a second unidentified conductive element, and a visual and/or aural annunciator, the method comprising: connecting the tester output and input to separate conductive elements at one end of a group of conductive elements;connecting the probe output and input to separate conductive elements at another end of the group of conductive elements; andestablishing that the conductive elements to which the tester and probe are connected are the same by a first annunciation by the tester.

8. The method of claim 7 further comprising establishing the polarity of the conductive elements to which the tester and probe are connected by a second annunciation by the tester.

9. The method of claim 8 in which the first and second annunciation by the tester comprise two different color lights.

10. The method of claim 9 in which the two different color lights are from a bi-color, bi-directional LED.