Prosecution Insights
Last updated: April 19, 2026
Application No. 18/669,638

METHOD AND DEVICE FOR TESTING PROTECTION RELAYS

Non-Final OA §103
Filed
May 21, 2024
Examiner
ASTACIO-OQUENDO, GIOVANNI
Art Unit
2858
Tech Center
2800 — Semiconductors & Electrical Systems
Assignee
Megger Sweden AB
OA Round
1 (Non-Final)
88%
Grant Probability
Favorable
1-2
OA Rounds
2y 4m
To Grant
99%
With Interview

Examiner Intelligence

Grants 88% — above average
88%
Career Allow Rate
632 granted / 714 resolved
+20.5% vs TC avg
Moderate +10% lift
Without
With
+10.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 4m
Avg Prosecution
17 currently pending
Career history
731
Total Applications
across all art units

Statute-Specific Performance

§101
13.9%
-26.1% vs TC avg
§103
33.0%
-7.0% vs TC avg
§102
14.5%
-25.5% vs TC avg
§112
33.0%
-7.0% vs TC avg
Black line = Tech Center average estimate • Based on career data from 714 resolved cases

Office Action

§103
DETAILED ACTION Notice of Pre-AIA or AIA Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status. Claims 1 – 18 are pending. Claim Objections Claim 1 is objected to because of the following informalities: line 3 should recite –to [[the]] current outputs--. Appropriate correction is required. Claim Rejections - 35 USC § 103 The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action: A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made. Claim(s) 1, 17, and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kwon et al. (US 2020/0021100 A1; hereinafter Kwon) in view of Adolfsson et al. (US 2006/0170432 A1; hereinafter Adolfsson). Regarding Claim 1, Kwon discloses an analog accessory for use in a system for testing protection relays (Fig. 1, item 100), comprising: PNG media_image1.png 596 518 media_image1.png Greyscale - inputs (Fig. 1, items 110 and 120; Test Current) connectable to [[the]] current outputs (Fig. 1, Test Current) of a test-set for protection relays (Fig. 1, item 200) - voltage outputs (Fig. 1, items 110 and 120; Test Voltage) connectable to a protection relay to be tested (Fig. 1, item 300), and - an electric circuit adapted to convert current provided by the test-set into a voltage signal on the voltage outputs (Fig. 1 and para [0042]; measurement unit 150 may include a current transformer). But Kwon does not specifically teach that simulates an output of a Rogowski sensor. However, Adolfsson suggests that simulates an output of a Rogowski sensor (para [0032]; allow measuring equipment according to the invention also to comprise a current-measuring means, such as a Rogowski coil). It would have been obvious to one of ordinary skill in the art before the effective filling date of the invention to modify Kwon in view of Adolfsson because resultant output voltage from a Rogowski coil increases proportionally with the frequency and is thus advantageous when detecting harmonics with low amplitude (Adolfsson, para [0032]). Regarding Claim 17, Kwon discloses a system for testing protection relays (para [0005]; protective relay test equipment operation device and method), the system comprising: - a relay test-set for protection relays (para[0006]; a protective relay test equipment operation device electrically connected to the test equipment) provided with current outputs (Fig. 1, Test Current) adapted to provide a current representing a fault condition (para[0073]; the protective relay test equipment operation device may set device operating times, receive fault voltage and current such as the test voltage and the test current), - a protection relay to be tested (Fig. 1, item 300), and - an analog accessory (Fig. 1, item 100) according to claim 1, - wherein the inputs (Fig. 1, items 110 and 120; Test Current) of the analog accessory are connected to the current outputs (Fig. 1, Test Current) of the test set (Fig. 1, item 200) and the voltage outputs (Fig. 1, items 110 and 120; Test Voltage) of the analog accessory (Fig. 1, item 100) are connected to the protection relay to be tested (Fig. 1, item 300), and - wherein the analog accessory (Fig. 1, item 100) is provided with an electric circuit that converts the current provided by the test-set into a voltage signal (Fig. 1 and para [0042]; measurement unit 150 may include a current transformer). Regarding Claim 18, Kwon discloses a method of testing protection relays (para [0005]; protective relay test equipment operation device and method), the method comprising the following steps: - providing, by means of a relay test-set (para[0006]; a protective relay test equipment operation device electrically connected to the test equipment), a user settable primary current representing a fault condition (para [0073]; the protective relay test equipment operation device may set device operating times such as the first and second reference times, receive fault voltage and current such as the test voltage and the test current). But Kwon does not specifically teach - providing, by means of an analog accessory, a voltage signal representing the derivative of the primary current by simulating the behavior of a Rogowski coil, and - supplying the voltage signal to a protection relay to be tested, wherein the relay test-set is set in a mode for a Rogowski coil. However, Adolfsson suggests that simulates an output of a Rogowski sensor (para [0032]; allow measuring equipment according to the invention also to comprise a current-measuring means, such as a Rogowski coil, for current and voltage). It would have been obvious to one of ordinary skill in the art before the effective filling date of the invention to modify Kwon in view of Adolfsson because resultant output voltage from a Rogowski coil increases proportionally with the frequency and is thus advantageous when detecting harmonics with low amplitude (Adolfsson, para [0032]). Claim(s) 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kwon in view of Adolfsson, and further in view of Nandi et al. (US 2015/0311788 A1; hereinafter Nandi). Regarding Claim 2, Kwon and Adolfsson disclose the analog accessory according to claim 1, Adolfsson also suggests wherein the voltage signal on the voltage outputs, during operation, simulates an output of a Rogowski sensor (para [0009]; voltage measuring device and para [0032]; allow measuring equipment according to the invention also to comprise a current-measuring means, such as a Rogowski coil). But Kwon and Adolfsson do not specifically teach including steady state and transient conditions in the time domain. However, Nandi suggests including steady state and transient conditions (para [0008]; steady state and transient performance can be achieved that is comparable to schemes with sensed current) in the time domain (para [0006]; discrete time domain versions suitable for microcontroller implementation with or without compensating for circuit non-idealities using stored or computed duty cycle patterns have also been examined). It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to modify the combination of Kwon and Adolfsson in view of Nandi in order to provide an accurate, sensorless current measurement or estimation scheme (Nandi, para [0003]). Allowable Subject Matter Claim 3 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. Regarding Claim 3, the prior art of record does not teach claimed limitation: “wherein the electric circuit comprises a transformer having a core, a primary winding electrically connected to the inputs and a secondary winding electrically connected to the voltage outputs” in combination with all other claimed limitations of claim 3. Regarding Claims 2 – 16, the claims are allowed as they further limit allowed claim 3. Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: Liu et al. (US 2012/0153931 A1) teaches that a Rogowski coil may be selected for the current sensor (see para [0020]). Nylen (US 3,696,296) suggests means for testing electrical equipment, such as relay protection means and automatic equipment, which comprises a test-rig (see claim 1). Sheth et al. (US 12,394,973 B2) discloses the fault detector differentiates a normal condition, a fault, an overload and a transient (e.g., without limitation, an inrush current) using existing current sensors (e.g., without limitation, a Rogowski coil) and an established algorithm such as, e.g., without limitation, a 3-sample Mann Morrison algorithm to electrical signals that may include transients; although the 3-sample algorithm is applicable only to noise-free steady state estimations requiring lower sampling frequencies (see column 2, lines 54 – 63). Any inquiry concerning this communication or earlier communications from the examiner should be directed to GIOVANNI ASTACIO-OQUENDO whose telephone number is (571)270-5724. The examiner can normally be reached Monday - Friday, 8:00am - 5:00pm. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Huy Phan can be reached at 571-272-7924. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /GIOVANNI ASTACIO-OQUENDO/Primary Examiner, Art Unit 2858 2/7/2026
Read full office action

Prosecution Timeline

May 21, 2024
Application Filed
Feb 07, 2026
Non-Final Rejection — §103 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
88%
Grant Probability
99%
With Interview (+10.2%)
2y 4m
Median Time to Grant
Low
PTA Risk
Based on 714 resolved cases by this examiner. Grant probability derived from career allow rate.

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