The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 10, 2026
Filed:
Jan. 19, 2024
Hella Gmbh & Co. Kgaa, Lippstadt, DE;
Alan Wayne Brown, Canton, MI (US);
HELLA GMBH & CO. KGAA, Lippstadt, DE;
Abstract
A method for monitoring the line impedance of a protective earth ('PE') conductor is provided. The method injects a small stimulus current at a frequency much higher than the grid frequency. The stimulus current circulates in the loops between a grid-connected device and a grid source, creating small voltage drops in the grid conductors, resulting in a common mode voltage which can be measured. The method then includes measuring the common mode voltage and the residual current at a point of common coupling (“PCC”). The method then includes monitoring the resistive and reactive parts of the line impedance. For example, the method can monitor the line impedance and report a broken PE conductor or a high PE resistance, beyond a given threshold where safety becomes a concern.