US3696291A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Equipment for detecting improper wiring in portable installation
Assignee: Electronics Diversified Inc
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Filing: 1970-01-30
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Granted: 1972-10-03
•
Expires: 1990-01-30
Abstract
Abstract A power wiring error indicator for electrical equipment includes an indicator means coupled between equipment ground and the neutral terminal of a three-phase, four-wire system, or a single phase, three-wire system. Capacitors are connected between each line terminal and equipment ground to provide a return circuit for the indicator means.
Inventors
- 👤 Arthur P Horne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:02
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/50; G01R31/58
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
166 words
An electrical equipment comprising: plural terminal means for receiving electrical conductors for empowering said electrical equipment, said terminal means including a neutral terminal adapted for connection to a neutral line, and at least two line terminals wherein said two line terminals are adapted to receive lines providing separate voltages with respect to said neutral line for empowering said equipment, said equipment further including a circuit reference terminal adapted to receive an external ground connection separate from said electrical conductors for empowering said equipment, but selectively ungrounded, indicator means coupled between said neutral terminal and said reference terminal and responsive to a difference in voltage therebetween for delivering an indication upon improper energization of said terminaLs, and separate relatively high impedance means of substantially equal impedance coupled between each of said line terminals and said reference terminal for completing a circuit for establishing a phantom ground return for said means for delivering an indication in the absence of an external ground connection to said circuit reference terminal.
Claim 2
Dependent Claim
166 words
An electrical equipment comprising: plural terminal means for receiving electrical conductors for empowering said electrical equipment, said terminal means including a neutral terminal adapted for connection to a neutral line, and at least two line terminals wherein said two line terminals are adapted to receive lines providing separate voltages with respect to said neutral line for empowering said equipment, said equipment further including a circuit reference terminal adapted to receive an external ground connection separate from said electrical conductors for empowering said equipment, but selectively ungrounded, indicator means coupled between said neutral terminal and said reference terminal and responsive to a difference in voltage therebetween for delivering an indication upon improper energization of said terminaLs, and separate relatively high impedance means of substantially equal impedance coupled between each of said line terminals and said reference terminal for completing a circuit for establishing a phantom ground return for said means for delivering an indication in the absence of an external ground connection to said circuit reference terminal.
Claim 3
Dependent Claim
32 words
The equipment according to claim 1 wherein said means for delivering an indication comprises a neon lamp and a resistance in series therewith connected between said neutral terminal and said reference terminal.
Claim 4
Dependent Claim
21 words
The equipment according to claim 1 further including means on the load side of said terminal means for disconnecting said equipment.
Claim 5
Dependent Claim
31 words
The equipment according to claim 3 further including separate load circuits connected to said line terminals via the disconnecting means, said load circuits being returned in common to said neutral terminal.
Claim 6
Dependent Claim
90 words
The equipment according to claim 4 including three line terminals each adapted to be energized by a line providing a separate voltage with respect to neutral in a three phase system, and six load circuits for connection in pairs to said three line terminals by way of said disconnecting means, and means for alternatively connecting said load circuits in groups of three to each of a pair of said line terminals when only line terminals of said pair are energized with respect to neutral from a single phase, three-wire system.
Claim 7
Dependent Claim
161 words
An electrical equipment comprising: plural terminal means for receiving electrical conductors for empowering said electrical equipment, said terminal means including a neutral terminal adapted for connection to a neutral line and at least two line terminals wherein said two line terminals are adapted to receive lines providing separate voltages with respect to said neutral line for empowering said equipment, said equipment further including a circuit reference terminal adapted to receive an external ground connection separate from said electrical conductors for empowering said equipment, indicator means coupled between said neutral terminal and said reference terminal and responsive to a difference in voltage therebetween for delivering an indication upon improper energization of said terminals, and separate capacitor means of substantially equal impedance coupled between each of said line terminals and said reference terminal for completing a circuit for establishing a phantom ground return for said means for delivering an indication in the absence of an external ground connection to said circuit reference terminal.
Claim 8
Dependent Claim
161 words
An electrical equipment comprising: plural terminal means for receiving electrical conductors for empowering said electrical equipment, said terminal means including a neutral terminal adapted for connection to a neutral line and at least two line terminals wherein said two line terminals are adapted to receive lines providing separate voltages with respect to said neutral line for empowering said equipment, said equipment further including a circuit reference terminal adapted to receive an external ground connection separate from said electrical conductors for empowering said equipment, indicator means coupled between said neutral terminal and said reference terminal and responsive to a difference in voltage therebetween for delivering an indication upon improper energization of said terminals, and separate capacitor means of substantially equal impedance coupled between each of said line terminals and said reference terminal for completing a circuit for establishing a phantom ground return for said means for delivering an indication in the absence of an external ground connection to said circuit reference terminal.
Claim 9
Dependent Claim
164 words
An electrical equipment comprising: plural terminal means for receiving electrical conductors for empowering said electrical equipment, said terminal means including a neutral terminal adapted for connection to a neutral line, and at least two line terminals wherein said two line terminals are adapted to receive lines providing separate voltages with respect to said neutral line for empowering said equipment, said equipment further including a circuit reference terminal adapted to receive an external ground connection separate from said electrical conductors for empowering said equipment, indicator means coupled between said neutral terminal and said reference terminal and responsive to a difference in voltage therebetween for delivering an indication upon improper energization of said terminals, and separate relatively high impedance capacitor means of substantially equal impedance coupled between each of said line terminals and said reference terminal for completing a circuit for establishing a phantom ground return for said means for delivering an indication in the absence of an external ground connection to said circuit reference terminal.
Claim 10
Dependent Claim
164 words
An electrical equipment comprising: plural terminal means for receiving electrical conductors for empowering said electrical equipment, said terminal means including a neutral terminal adapted for connection to a neutral line, and at least two line terminals wherein said two line terminals are adapted to receive lines providing separate voltages with respect to said neutral line for empowering said equipment, said equipment further including a circuit reference terminal adapted to receive an external ground connection separate from said electrical conductors for empowering said equipment, indicator means coupled between said neutral terminal and said reference terminal and responsive to a difference in voltage therebetween for delivering an indication upon improper energization of said terminals, and separate relatively high impedance capacitor means of substantially equal impedance coupled between each of said line terminals and said reference terminal for completing a circuit for establishing a phantom ground return for said means for delivering an indication in the absence of an external ground connection to said circuit reference terminal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-03 | 1976-04-03 | 1976-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-03 | 1980-04-03 | 1980-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-03 | 1984-04-03 | 1984-10-03 | $7700.00 | Window Closed / Lapsed |