# US 10,371,739 B2 · Arrangement for detecting a meter maintenance condition using winding resistance > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,739 B2 - Document ID: US10371739B2 - Status: Granted - Kind: B2 - Application number: 14/928,995 - Filed: 2015-10-30 - Published: 2017-05-04 - Granted: 2019-08-06 - Earliest claimed: 2015-10-30 - Assignees: Landis+Gyr, Inc. - Applicants: Landys+Gyr LLC - Inventors: John T. Voisine - Web page: https://patentgrep.com/patent/US10371739B2 ## CPC - G01K 7/16: using resistive elements - G01N 25/72: Investigating presence of flaws - G01R 31/67: Testing the correctness of wire connections in electric apparatus or circuits - G01K 2217/00: Temperature measurement using electric or magnetic components already present in the system to be measured - G01R 21/00: Arrangements for measuring electric power or power factor (G01R7/12 takes precedence) - G01R 31/72: Testing of electric windings (testing of transformers G01R31/62) - H02H 7/04: for transformers - G01K: MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR (radiation pyrometry G01J5/00) - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H02H: EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS (indicating or signalling undesired working conditions G01R, e.g. G01R31/00, G08B; locating faults along lines G01R31/08; emergency protective devices H01H) ## Abstract An arrangement for use in a utility meter is disclosed. The arrangement includes a meter blade coupled to a current coil. The arrangement further includes a current sensor that includes a winding about a core. The current sensor is in a current sensing relationship with the current coil. The winding has a resistance that varies as a function of temperature. The arrangement further includes a processing circuit that is operably coupled to receive a measurement signal from the winding. The processing circuit is configured to determine a DC component of the measurement signal, determine the resistance of the winding based at least in part on the determined DC component, and cause a value representative of the determined resistance to be displayed or communicated to an external device. ## Claims ### Claim 1 An arrangement for use in a utility meter, comprising: a meter blade coupled to a current coil; a current sensor including a winding about a core, the current sensor in a current sensing relationship with the current coil, the winding having a resistance that varies as a function of temperature; a processing circuit operably coupled to receive a measurement signal from the winding, the processing circuit configured to: determine a DC component of the measurement signal; determine the resistance of the winding based at least in part on the determined DC component; and cause a value representative of the determined resistance to be displayed or communicated to an external device. ### Claim 2 (depends on 1) The arrangement of claim 1, further comprising: a DC application circuit configured to apply a DC voltage across the winding. ### Claim 3 (depends on 2) The arrangement of claim 2, wherein the DC application circuit includes: a DC voltage source operably connected across the winding to apply at least one volt DC to the winding. ### Claim 4 (depends on 3) The arrangement of claim 3, wherein the DC application circuit includes a switch configured to connect and disconnect the DC voltage source across the winding. ### Claim 5 (depends on 4) The arrangement of claim 4, wherein the processing circuit is configured to control the switch. ### Claim 6 (depends on 1) The arrangement of claim 1, wherein the processing circuit is further configured to determine the resistance of the winding based in part on a comparison of the determined DC component and a previously-determined DC component of the measurement signal. ### Claim 7 (depends on 1) The arrangement of claim 1, wherein the value representative of the determined resistance is a temperature measurement value representative of a temperature of the winding, and wherein the processing circuit is further configured to determine the temperature measurement value based in part on the determined resistance. ### Claim 8 (depends on 5) The arrangement of claim 5, wherein: the DC voltage across the winding corresponds to the DC component in the measurement signal; and the DC application circuit further comprises a burden resistor coupled from a first terminal of the winding to a first reference node, a first resistor serially coupled between a second terminal of the winding and the first reference node, and a second resistor having a first side coupled to the second terminal of the winding and a second side coupled to be at a reference voltage; and the DC voltage source is operably connected between the first reference node and the reference voltage to provide a DC voltage to the first reference node. ### Claim 9 (depends on 8) The arrangement of claim 8, wherein the switch is configured to open and close a circuit from the second terminal of the winding to the reference voltage through the second resistor. ### Claim 10 (depends on 9) The arrangement of claim 9, further comprising a second switch operably coupled to controllably and operably disconnect a first path from the DC voltage to the first reference node such that a voltage other than the DC voltage is provided to the first reference node. ### Claim 11 (depends on 10) The arrangement of claim 10, wherein: the DC voltage is configured to provide the DC voltage to a second reference node; the first path extends from the first reference node to the second reference node; and further comprising, a third resistor serially coupled from the second reference node to the first terminal, and a fourth resistor serially coupled from the second reference node to the first reference node in parallel to the first path. ### Claim 12 (depends on 11) The arrangement of claim 11, wherein a resistance value of the second resistor exceeds a resistance value of the first resistor, and the resistance value of the first resistor exceeds a resistance value of the burden resistor. ### Claim 13 (depends on 9) The arrangement of claim 9, wherein a resistance value of the second resistor exceeds a resistance value of the first resistor, and the resistance value of the first resistor exceeds a resistance value of the burden resistor. ### Claim 14 (depends on 2) The arrangement of claim 2, wherein: the winding comprises a first terminal and a second terminal; the DC voltage across the winding corresponds to the DC component in the measurement signal; and the DC application circuit further comprises a burden resistor coupled from a first terminal of the winding to a first reference node, a first resistor serially coupled between the second terminal of the winding and the first reference node, and a second resistor having a first side coupled to the second terminal of the winding and a second side coupled to be at a reference voltage; and a DC voltage source is operably connected between the first reference node and the reference voltage to provide a DC voltage to the first reference node. ### Claim 15 (depends on 14) The arrangement of claim 14, wherein a resistance value of the second resistor exceeds a resistance value of the first resistor, and the resistance value of the first resistor exceeds a resistance value of the burden resistor. ### Claim 16 (depends on 1) The arrangement of claim 1, further comprising a display operably connected to the processing circuit. ### Claim 17 An arrangement for use in a utility meter, comprising: a meter blade coupled to a current coil; a current sensor including a winding about a core, the current sensor in a current sensing relationship with the current coil, the winding having a resistance that varies as a function of temperature; a processing circuit operably coupled to receive a measurement signal from the winding, the processing circuit configured to: determine a DC component of the measurement signal; determine the resistance of the winding based at least in part on the determined DC component; and store a value representative of the determined resistance. ### Claim 18 (depends on 17) The arrangement of claim 17, further comprising a DC application circuit that includes: a DC voltage source operably connected across the winding to apply at least approximately one volt DC to the winding. ### Claim 19 (depends on 18) The arrangement of claim 18, wherein the DC application circuit includes a switch, the switch configured to controllably operably connect and disconnect the DC voltage source across the winding.