Patent DE480774C successfully refreshed from Google Patents.
EP0054940A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Non-grounding checking system
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1981-12-18
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Granted: —
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Expires: 2001-12-18
Abstract
Abstract The grounding of an electrical apparatus is monitored by a primary circuit (8) which is inductively coupled to a coil (L 2 ) connected in series between the grounding line (4a) of the power J (4) a d a grounding terminal (12a) on the electrical apparat a which a second grounding line (10) is connected.
Inventors
- 👤 Kenichi Yoshida
- 👤 Junichi Hiramoto
- 👤 Shinya Takenaka
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 18:38
CPC Classifications
H; H02; H02H; H02H11/00; H02H11/001; G; G01; G01R; G01R27/00; G01R27/02; G01R27/20; G01R27/205; G01R31/00; G01R31/50; G01R31/58
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
89 words
1 . In an electrical apparatus having a power cord with a first grounding line therein, said apparatus having a grounding terminal.to which a second grounding line is connected, a non-grounding checking circuit comprising: a primary circuit including a primary coil and electric source means for providing a current through said primary coil; and a secondary coil connected in series between said first grounding line and grounding terminal and inductively coupled to said primary coil, the impedance of said primary circuit indicating the grounding state of said electrical apparatus.
Claim 2
Dependent Claim
89 words
1 . In an electrical apparatus having a power cord with a first grounding line therein, said apparatus having a grounding terminal.to which a second grounding line is connected, a non-grounding checking circuit comprising: a primary circuit including a primary coil and electric source means for providing a current through said primary coil; and a secondary coil connected in series between said first grounding line and grounding terminal and inductively coupled to said primary coil, the impedance of said primary circuit indicating the grounding state of said electrical apparatus.
Claim 3
Dependent Claim
26 words
A non-grounding checking circuit as claimed in claim 1, wherein said primary circuit includes'a resistor connected in series with said primary coil and electric source means.
Claim 4
Dependent Claim
19 words
A non-grounding checking circuit as claimed in claim 2, further comprising means for monitoring the voltage across said resistor.
Claim 5
Dependent Claim
19 words
A non-grounding checking circuit as claimed in claim 2, further comprising means for monitoring the current through said resistor.
References Cited (Backward Citations)
AT268448B
Cited
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