US5119031A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for monitoring the integrity of a multiple-planes grounding system
Assignee: Nortel Networks Ltd
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Filing: 1990-11-23
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Granted: 1992-06-02
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Expires: 2010-11-23
Abstract
Abstract A ground integrity monitor for testing for a short circuit between two equipotential ground planes having a single common connection point includes an AC generating circuit for coupling to one of the ground planes a signal having predetermined frequency and magnitude characteristics. An AC detecting circuit coupled to the other of the ground planes is adapted to detect the AC signal within a predetermined range of magnitude and frequency. Presence of the signal on the other ground plane indicates the existence of a short circuit.
Inventors
- 👤 Reginald M. Foulkes
- 👤 Albert S. Ashdown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:55
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/50; G01R31/52
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
117 words
A ground integrity monitor, for use in a grounding system of a telecommunications system, the grounding system having at least first and second ground planes connected at a single common electrical point, the monitor comprising: (a) an alternating current generator circuit electrically coupled to the first ground plane for coupling thereto an alternating current signal having predetermined frequency and magnitude characteristics; and (b) an alternating current signal detector circuit electrically coupled to the second ground plane for detecting an alternating current signal having a frequency corresponding to the predetermined frequency, whereby detection of the signal indicates the existence of an undesirable connection between the ground planes at a location other than the single common electrical connection point.
Claim 2
Dependent Claim
117 words
A ground integrity monitor, for use in a grounding system of a telecommunications system, the grounding system having at least first and second ground planes connected at a single common electrical point, the monitor comprising: (a) an alternating current generator circuit electrically coupled to the first ground plane for coupling thereto an alternating current signal having predetermined frequency and magnitude characteristics; and (b) an alternating current signal detector circuit electrically coupled to the second ground plane for detecting an alternating current signal having a frequency corresponding to the predetermined frequency, whereby detection of the signal indicates the existence of an undesirable connection between the ground planes at a location other than the single common electrical connection point.
Claim 3
Dependent Claim
33 words
A ground integrity monitor as defined in claim 1 wherein the alternating current generator circuit and the alternating current signal detector circuit are inductively coupled to the first and second ground planes respectively.
Claim 4
Dependent Claim
29 words
A ground integrity monitor as defined in claim 2 wherein the predetermined frequency does not correspond to any multiple or submultiple of frequencies of signals used the telecommunications system.
Claim 5
Dependent Claim
17 words
A ground integrity monitor as defined in claim 2 wherein the predetermined frequency is approximately 9.4 Khz.
Claim 6
Dependent Claim
136 words
A ground integrity monitor for use in a grounding system of a telecommunications system, the grounding system having at least first and second ground planes connected at a single common electrical connection point, the monitor comprising: (a) an alternating current generator circuit electrically coupled to the first ground plane for coupling thereto an alternating current signal having predetermined frequency and magnitude characteristics, the predetermined frequency not corresponding to any multiple or submultiple of frequencies of signals used within the telecommunications system; and (b) an alternating current signal detector circuit electrically coupled to the second ground plane for detecting an alternating current signal having a frequency corresponding to the predetermined frequency, detection of the signal indicating the existence of an undesirable connection between the ground planes and the connection having an impedance approximately 400 ohms or less.
Claim 7
Dependent Claim
136 words
A ground integrity monitor for use in a grounding system of a telecommunications system, the grounding system having at least first and second ground planes connected at a single common electrical connection point, the monitor comprising: (a) an alternating current generator circuit electrically coupled to the first ground plane for coupling thereto an alternating current signal having predetermined frequency and magnitude characteristics, the predetermined frequency not corresponding to any multiple or submultiple of frequencies of signals used within the telecommunications system; and (b) an alternating current signal detector circuit electrically coupled to the second ground plane for detecting an alternating current signal having a frequency corresponding to the predetermined frequency, detection of the signal indicating the existence of an undesirable connection between the ground planes and the connection having an impedance approximately 400 ohms or less.
Claim 8
Independent Claim
78 words
A method of determining the presence of a low impedance connection between first and second ground planes having a common electrical connection point therebetween, the method comprising the steps of coupling an alternating current signal having a predetermined frequency on one of the ground planes and detecting any resulting alternating current signal having the predetermined frequency of the second ground plane, any such detection indicating the existence of an undesirable connection between the first and second ground planes.
Claim 9
Independent Claim
78 words
A method of determining the presence of a low impedance connection between first and second ground planes having a common electrical connection point therebetween, the method comprising the steps of coupling an alternating current signal having a predetermined frequency on one of the ground planes and detecting any resulting alternating current signal having the predetermined frequency of the second ground plane, any such detection indicating the existence of an undesirable connection between the first and second ground planes.
Claim 10
Dependent Claim
113 words
In a telecommunications system, a method of determining the existence of a low impedance connection between first and second ground planes of a grounding system, the ground planes having a common electrical connection point therebetween, the method comprising the steps of coupling an alternating current signal having a predetermined frequency not corresponding to any multiple or submultiple of frequencies within the telecommunications system on one of the ground planes, and detecting any resulting alternating current signal having the predetermined frequency on the second ground plane, whereby the presence of any coupled signal on the second ground plane indicates the existence of a low impedance connection between the first and the second ground planes.
Claim 11
Dependent Claim
113 words
In a telecommunications system, a method of determining the existence of a low impedance connection between first and second ground planes of a grounding system, the ground planes having a common electrical connection point therebetween, the method comprising the steps of coupling an alternating current signal having a predetermined frequency not corresponding to any multiple or submultiple of frequencies within the telecommunications system on one of the ground planes, and detecting any resulting alternating current signal having the predetermined frequency on the second ground plane, whereby the presence of any coupled signal on the second ground plane indicates the existence of a low impedance connection between the first and the second ground planes.
Claim 12
Dependent Claim
21 words
A method as defined in claim 7 wherein the low impedance connection has a impedance of approximately 400 ohms or less.
Claim 13
Independent Claim
83 words
A method of ensuring that proper isolation exists between the ground planes of a grounding system comprising the steps of: (a) coupling an alternating current signal having a predetermined frequency not corresponding to any multiple or submultiple of frequencies within the telecommunications system on one of the ground planes; and (b) monitoring the other of the ground planes for the presence of an alternating current signal having the predetermined frequency, whereby such presence indicates the existence of improper isolation between the ground planes.
Claim 14
Independent Claim
83 words
A method of ensuring that proper isolation exists between the ground planes of a grounding system comprising the steps of: (a) coupling an alternating current signal having a predetermined frequency not corresponding to any multiple or submultiple of frequencies within the telecommunications system on one of the ground planes; and (b) monitoring the other of the ground planes for the presence of an alternating current signal having the predetermined frequency, whereby such presence indicates the existence of improper isolation between the ground planes.
References Cited (Backward Citations)
US4228475A
Cited
US4991105A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-06-02 | 1995-12-02 | 1996-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-02 | 1999-12-02 | 2000-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-02 | 2003-12-02 | 2004-06-02 | $7700.00 | Window Closed / Lapsed |