# US 2020/0403402 A1 · Novel overvoltage protective device for lightning protection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0403402 A1 - Document ID: US20200403402A1 - Status: Published application - Kind: A1 - Application number: 16/975,135 - Filed: 2019-07-01 - Published: 2020-12-24 - Earliest claimed: 2018-07-12 - Assignees: Chengdu Tieda Electronics Corp. - Applicants: Chengdu Tieda Electronics Corp. - Inventors: Zhicheng Zhang; Lei Ye; Jungu Zhan; Jun Zhang; Xiaolong Shi - Web page: https://patentgrep.com/patent/US20200403402A1 ## CPC - H02H 9/045: {adapted to a particular application and not provided for elsewhere} - H01C 7/02: having positive temperature coefficient - H01C 7/12: Overvoltage protection resistors; Arresters - H01C 7/126: {Means for protecting against excessive pressure or for disconnecting in case of failure} - H02H 9/04: responsive to excess voltage (lightning arrestors H01C7/12, H01C8/04, H01G9/18, H01T) - H02H 9/041: {using a short-circuiting device} - H02H 9/042: {comprising means to limit the absorbed power or indicate damaged over-voltage protection device} - H01C 7/102: Varistor boundary, e.g. surface layers (H01C7/12 takes precedence) - H01C 7/18: comprising a plurality of layers stacked between terminals - H02H 1/04: Arrangements for preventing response to transient abnormal conditions, e.g. to lightning {or to short duration over voltage or oscillations; Damping the influence of DC component by short circuits in AC networks} - H02H 3/22: of short duration, e.g. lightning - H02H 9/06: using spark-gap arresters - 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) - H01C: RESISTORS ## Abstract Disclosed in the present invention is a novel overvoltage protective device for lightning protection, comprising a first varistor, a second varistor, a PTC Thermistor, and lead-out terminals. The first varistor and the PTC Thermistor are connected in parallel, and then further connected in series with the second varistor to form a single port combined circuit. The surge-withstand capability of the first varistor is higher than the surge-withstand capability of the second varistor. At least one of the two lead-out terminals of the single port combined circuit is a thermally-conductive end with low thermal resistance. The second varistor is thermally coupled to the PTC Thermistor. The thermally-conductive end with low thermal resistance is thermally coupled to one or both of the second varistor and the PTC Thermistor. ## Claims ### Claim 1 A novel overvoltage protective device for lightning protection includes a first varistor (3), a second varistor (1), a PTC Thermistor (2), and lead-out terminals (4), and the first varistor (3) and the PTC Thermistor (2) are connected in parallel, and then further connected in series with the second varistor (1) to form a single port combined circuit, and surge-withstand capability of the first varistor (3) is higher than surge-withstand capability of the second varistor (1); at least one of the two lead-out terminals (4) of the single port combined circuit is a thermally-conductive end with low thermal resistance, and the second varistor (1) is thermally coupled to the PTC Thermistor (2), and the thermally-conductive end with low thermal resistance is thermally coupled to one or both of the second varistor (1) and the PTC Thermistor (2). ### Claim 2 (depends on 1) The novel overvoltage protective device for lightning protection according to claim 1, wherein, first varistor electrode surface's (31) area of the first varistor (3) is larger than second varistor electrode surface's (1) area of the second varistor (1). ### Claim 3 (depends on 1) The novel overvoltage protective device for lightning protection according to claim 1, wherein, nominal diameter of the first varistor (3) is at least one serial number larger than nominal diameter of the second varistor (1). ### Claim 4 (depends on 1) The novel overvoltage protective device for lightning protection according to claim 1, wherein, varistor voltage value of the first varistor (3) is 0.9 to 1.1 times peak value of operating voltage of the connected power grid. ### Claim 5 (depends on 1) The novel overvoltage protective device for lightning protection according to claim 1, wherein, one second varistor electrode surface (11) of the second varistor (1) is connected with the PTC Thermistor (2) and one electrode (31) of the first varistor , the other electrode of the PTC Thermistor is connected with another electrode (31) of the first varistor (3), and the second varistor (1) and/or the PTC Thermistor (2) is also soldered with a thermally-conductive end with low thermal resistance. ### Claim 6 (depends on 5) The novel overvoltage protective device for lightning protection according to claim 5, wherein, the second varistor (1), the PTC Thermistor (2), and the first varistor (3) are packaged as a whole. ### Claim 7 (depends on 1) The novel overvoltage protective device for lightning protection according to claim 1, wherein, the rated value of the impulse discharge current of the first varistor (3) is higher than the rated value of the impulse discharge current of the second varistor (1). ### Claim 8 (depends on 1) The novel overvoltage protective device for lightning protection according to claim 1, wherein, when power grid with power frequency voltage 220V is connected, the varistor voltage value of the first varistor (3) is 280V-342V; when power grid with power frequency voltage 110V is connected, the varistor voltage value of the first varistor (3) is 140V-171V; when power grid with power frequency voltage 380V is connected, the varistor voltage value of the first varistor (3) is 484V-591V. ### Claim 9 A novel overvoltage protective device for lightning protection includes a first varistor (3), a second varistor (1), a PTC Thermistor (2), and lead-out terminals (4), and the first varistor (3) and the PTC Thermistor (2) are in parallel, and then further connected in series with the second varistor (1) to form a single port combined circuit, and the surge-withstand capability of the first varistor (3) is higher than the surge-withstand capability of the second varistor (1); at least one of the two lead-out terminals (4) of the single port combined circuit is a thermally-conductive end with low thermal resistance, and the thermally-conductive end with low thermal resistance is thermally coupled to one or both of the second varistor (1) and the PTC Thermistor (2). ### Claim 10 (depends on 1) The novel overvoltage protective device for lightning protection according to claim 1, wherein, the PTC Thermistor (2) can be replaced with a resistor with linear characteristics. ### Claim 11 (depends on 2) The novel overvoltage protective device for lightning protection according to claim 2, wherein, the PTC Thermistor (2) can be replaced with a resistor with linear characteristics. ### Claim 12 (depends on 3) The novel overvoltage protective device for lightning protection according to claim 3, wherein, the PTC Thermistor (2) can be replaced with a resistor with linear characteristics. ### Claim 13 (depends on 4) The novel overvoltage protective device for lightning protection according to claim 4, wherein, the PTC Thermistor (2) can be replaced with a resistor with linear characteristics. ### Claim 14 (depends on 5) The novel overvoltage protective device for lightning protection according to claim 5, wherein, the PTC Thermistor (2) can be replaced with a resistor with linear characteristics. ### Claim 15 (depends on 6) The novel overvoltage protective device for lightning protection according to claim 6, wherein, the PTC Thermistor (2) can be replaced with a resistor with linear characteristics. ### Claim 16 (depends on 7) The novel overvoltage protective device for lightning protection according to claim 7, wherein, the PTC Thermistor (2) can be replaced with a resistor with linear characteristics. ### Claim 17 (depends on 8) The novel overvoltage protective device for lightning protection according to claim 8, wherein, the PTC Thermistor (2) can be replaced with a resistor with linear characteristics. ### Claim 18 (depends on 9) The novel overvoltage protective device for lightning protection according to claim 9, wherein, the PTC Thermistor (2) can be replaced with a resistor with linear characteristics.