US4223265A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-impedance and wide-band voltage probe for the selective measurement of interference voltages
Assignee: BBC Brown Boveri AG Switzerland
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Filing: 1978-08-15
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Granted: 1980-09-16
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Expires: 1998-08-15
Abstract
Abstract A probe adapted for selectively measuring either symmetrical or asymmetrical interference voltages or interference voltages between terminal and ground and utilizing first and second transformers having interconnected primary windings and tightly magnetically coupled secondary windings connectible with the interference measuring set for optionally measuring either symmetrical or asymmetrical voltages or voltages against ground, is disclosed. When measuring a balanced (symmetrical) voltage the terminals of the first transformer primary winding are coupled to the opposite poles of the specimen under test. When measuring an unbalanced (asymmetrical) voltage or a voltage with respect to ground, both terminals of the first transformer winding are connected in common to the pole of the specimen under test. In an cases a single ground terminal of the probe is connected to the ground of the specimen under test. Measurements of the symmetrical and asymmetrical interference voltages may be taken without removing the probe from the specimen under test by simply connecting the cable from the measuring set to the connectors "sym" or "asym" respectively and by reconnecting the probe to the specimen under test in the manner described above. The circuits under test need not be removed from their operating environment. The circuit design of the probe permits the conditions for symmetry to be easily and redialy established.
Inventors
- 👤 Eugene Simmen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:33
CPC Classifications
G; G01; G01R; G01R23/00; G01R23/16; G01R23/20; G01R19/00; G01R19/145; G01R19/155
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
336 words
A voltage probe capable of measuring the balanced and unbalanced components of an interference voltage generated by a specimen under test, said specimen having first and second terminals, said probe comprising: (A) a first transformer (Tr 1 ) including only one primary winding (P 1 ) and only one secondary winding (S 1 ), said first transformer primary winding having opposite end terminals and a center tap; (B) a second transformer (Tr 2 ) including only one primary winding (P 2 ) and only one secondary winding (S 2 ), said second transformer primary winding (P 2 ) having opposite end terminals, one of said end terminals of said second transformer primary winding (P 2 ) being connected to said first transformer primary winding (P 1 ) center tap, the remaining said end terminal of said second transformer primary winding (P 2 ) being coupled to ground; (C) first connector means adapted to couple, at the option of the operator of said probe, one of said end terminals of said first transformer primary winding (P 1 ) to either of said first and second terminals of said specimen under test; and (D) second connector means adapted to couple, at the option of the operator of said probe, the remaining of said end terminals of said first transformer primary winding (P 1 ) to either of said first and second terminals of said specimen under test, whereby: (1) when said first and second connector means are each coupled to respective opposite terminals of said specimen under test, a voltage proportional to the balanced component of said interference voltage appears across said first transformer secondary winding (S 1 ); and (2) when said first and second connector means are both coupled to one another and to one of said terminals of said specimen under test and the remaining said terminal of said specimen under test is grounded, a voltage proportional to said unbalanced component of said interference voltage appears across said second transformer secondary winding (S 2 ).
Claim 2
Dependent Claim
336 words
A voltage probe capable of measuring the balanced and unbalanced components of an interference voltage generated by a specimen under test, said specimen having first and second terminals, said probe comprising: (A) a first transformer (Tr 1 ) including only one primary winding (P 1 ) and only one secondary winding (S 1 ), said first transformer primary winding having opposite end terminals and a center tap; (B) a second transformer (Tr 2 ) including only one primary winding (P 2 ) and only one secondary winding (S 2 ), said second transformer primary winding (P 2 ) having opposite end terminals, one of said end terminals of said second transformer primary winding (P 2 ) being connected to said first transformer primary winding (P 1 ) center tap, the remaining said end terminal of said second transformer primary winding (P 2 ) being coupled to ground; (C) first connector means adapted to couple, at the option of the operator of said probe, one of said end terminals of said first transformer primary winding (P 1 ) to either of said first and second terminals of said specimen under test; and (D) second connector means adapted to couple, at the option of the operator of said probe, the remaining of said end terminals of said first transformer primary winding (P 1 ) to either of said first and second terminals of said specimen under test, whereby: (1) when said first and second connector means are each coupled to respective opposite terminals of said specimen under test, a voltage proportional to the balanced component of said interference voltage appears across said first transformer secondary winding (S 1 ); and (2) when said first and second connector means are both coupled to one another and to one of said terminals of said specimen under test and the remaining said terminal of said specimen under test is grounded, a voltage proportional to said unbalanced component of said interference voltage appears across said second transformer secondary winding (S 2 ).
Claim 3
Dependent Claim
35 words
The voltage probe of claim 1, wherein each of said secondary windings (S 1 , S 2 ) of said two transformers (Tr 1 , Tr 2 ) consists of only a single twin winding.
Claim 4
Dependent Claim
36 words
A voltage probe according to claim 1, further including screening (T) at least partially surrounding said transformers (Tr 1 , Tr 2 ) to reduce the effect of RF type interference upon the measurements being taken.
Claim 5
Dependent Claim
24 words
A voltage probe according to claim 1, further including means for measuring the magnitude of the induced voltage appearing across said first secondary winding.
Claim 6
Dependent Claim
23 words
A voltage probe according to claim 1, further including means for measuring the magnitude of the induced voltage appearing across said secondary winding.
Claim 7
Dependent Claim
56 words
The voltage probe of claim 1, wherein said specimen under test is an electrical system connected to either a single phase A.C. source or a D.C. source and wherein said probe is capable of measuring said balanced and unbalanced components while said electrical system is connected to either said single phase A.C. or said D.C. source.
Claim 8
Dependent Claim
17 words
A voltage probe according to claim 1, wherein each of said connector means includes an isolating capacitor.
Claim 9
Dependent Claim
61 words
A voltage probe according to claim 7, wherein each of said connector means further includes a resistor of low ohmic value connected in series with said isolating capacitor, said resistor and said capacitor of each said connector means defining a filter circuit which permits passage of said interference voltages but filters out power source voltages applied to said specimen under test.
Claim 10
Independent Claim
157 words
A method for measuring the balanced component of an interference voltage generated by a specimen under test, said specimen having first and second opposite terminals, said method comprising the steps of: providing a voltage probe comprising: a first transformer including a primary winding and a secondary winding, said first transformer primary winding having opposite end terminals and a center tap; a second transformer including a primary winding and a secondary winding, said second transformer primary winding having opposite end terminals, one of said end terminals of said second transformer primary winding being connected to said center tap of said first transformer primary winding, the remaining said end terminal of said second transformer primary winding being coupled to ground; connecting said end terminals of said first transformer primary winding to respective opposite terminals of said specimen under test; and measuring a voltage, representative of said balanced component of said interference voltage, appearing across said first transformer secondary winding.
Claim 11
Independent Claim
157 words
A method for measuring the balanced component of an interference voltage generated by a specimen under test, said specimen having first and second opposite terminals, said method comprising the steps of: providing a voltage probe comprising: a first transformer including a primary winding and a secondary winding, said first transformer primary winding having opposite end terminals and a center tap; a second transformer including a primary winding and a secondary winding, said second transformer primary winding having opposite end terminals, one of said end terminals of said second transformer primary winding being connected to said center tap of said first transformer primary winding, the remaining said end terminal of said second transformer primary winding being coupled to ground; connecting said end terminals of said first transformer primary winding to respective opposite terminals of said specimen under test; and measuring a voltage, representative of said balanced component of said interference voltage, appearing across said first transformer secondary winding.
Claim 12
Independent Claim
176 words
A method for measuring the unbalanced component of an interference voltage generated by a specimen under test, said specimen having first and second opposite terminals, said method comprising the steps of: providing a voltage probe comprising: a first transformer including a primary winding and a secondary winding, said first transformer primary winding having opposite end terminals and a center tap; a second transformer including a primary winding and a secondary winding, said second transformer primary winding having opposite end terminals, one of said end terminals of said second transformer primary winding being connected to said center tap of said first transformer primary winding, the remaining said end terminal of said second transformer primary winding being coupled to ground; connecting both of said end terminals of said first transformer primary winding to each other and to a single one of said terminals of said specimen and connecting the remaining one of said terminals of said specimen to ground; measuring a voltage, representative of said unbalanced component of said interference voltage, appearing across said second transformer secondary winding.
Claim 13
Independent Claim
176 words
A method for measuring the unbalanced component of an interference voltage generated by a specimen under test, said specimen having first and second opposite terminals, said method comprising the steps of: providing a voltage probe comprising: a first transformer including a primary winding and a secondary winding, said first transformer primary winding having opposite end terminals and a center tap; a second transformer including a primary winding and a secondary winding, said second transformer primary winding having opposite end terminals, one of said end terminals of said second transformer primary winding being connected to said center tap of said first transformer primary winding, the remaining said end terminal of said second transformer primary winding being coupled to ground; connecting both of said end terminals of said first transformer primary winding to each other and to a single one of said terminals of said specimen and connecting the remaining one of said terminals of said specimen to ground; measuring a voltage, representative of said unbalanced component of said interference voltage, appearing across said second transformer secondary winding.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-09-16 | 1984-03-17 | 1984-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-16 | 1988-03-17 | 1988-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-16 | 1992-03-17 | 1992-09-16 | $7700.00 | Window Closed / Lapsed |