# US 10,504,677 B1 · Electronic circuit breaker with physical open-contact construction and fail-safe protection with disabling feature > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,504,677 B1 - Document ID: US10504677B1 - Status: Granted - Kind: B1 - Application number: 16/281,560 - Filed: 2019-02-21 - Granted: 2019-12-10 - Earliest claimed: 2019-02-21 - Applicants: Richard W. Sorenson - Inventors: Richard W. Sorenson - Web page: https://patentgrep.com/patent/US10504677B1 ## CPC - H01H 71/128: {Manual release or trip mechanisms, e.g. for test purposes (two similar push buttons for closing or resetting and opening or tripping H01H71/58; test switches for earth fault circuit breakers H01H83/04)} - H01H 47/002: {Monitoring or fail-safe circuits} - H01H 71/123: {using a solid-state trip unit (circuits H02H)} - H01H 71/2481: {characterised by the coil design} - H01H 71/50: Manual reset mechanisms {which may be also used for manual release} - H02H 3/044: {Checking correct functioning of protective arrangements, e.g. by simulating a fault (for differential current circuit breakers H02H3/335)} - H02H 3/05: with means for increasing reliability, e.g. redundancy arrangements {(for logic circuits H03K19/003)} - H01H 47/004: {using plural redundant serial connected relay operated contacts in controlled circuit} - H01H 47/22: for supplying energising current for relay coil - H01H 71/125: {characterised by sensing elements, e.g. current transformers (for differential protection H01H83/144)} - H01H 83/20: operated by excess current as well as by some other abnormal electrical condition - H01H 2001/506: {Fail safe contacts, i.e. the contacts being kept in a safe position, usually in an open circuit position, at end of life time of switch} - H01H 2071/044: {Monitoring, detection or measuring systems to establish the end of life of the switching device, can also contain other on-line monitoring systems, e.g. for detecting mechanical failures} - H01H 2205/002: fixed to operating part - H02H 3/08: responsive to excess current (responsive to abnormal temperature caused by excess current H02H5/04) - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) - 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 A circuit breaker includes contacts movable between a closed position wherein a line terminal and a load terminal are in electrical communication, and an open position wherein the line and the load terminals are electrically isolated. A primary trip coil and a secondary trip coil are connected to the contacts, each causing the contacts to move from the closed position to the open position when activated, thereby tripping the breaker. A monitoring circuit, upon a determination being made that the breaker is not operating within acceptable trip parameters, causes activation of the primary coil, and, upon a determination being made that the breaker is not operating within acceptable disable parameters, causes activation of the secondary coil. The breaker is user resettable if the breaker has been tripped by the primary trip coil, but is not user resettable if the breaker has been tripped by the secondary trip coil. ## Claims ### Claim 1 A circuit breaker comprising: a pair of main contacts movable with respect to each other between a closed position wherein a line terminal and a load terminal are in electrical communication with each other via a main power circuit, and an open position wherein the line terminal and the load terminal are electrically isolated from each other; a primary trip coil operably connected to at least one of said pair of main contacts, said primary trip coil causing said pair of main contacts to move from the closed position to the open position when activated, thereby tripping said circuit breaker; a secondary trip coil operably connected to at least one of said pair of main contacts, said secondary trip coil causing said pair of main contacts to move from the closed position to the open position when activated, thereby tripping said circuit breaker; a monitoring circuit monitoring operation of the circuit breaker; said monitoring circuit, upon a determination being made that said circuit breaker is not operating within acceptable trip parameters, causing activation of said primary trip coil, and said monitoring circuit, upon a determination being made that said circuit breaker is not operating within acceptable disable parameters, causing activation of said secondary trip coil; wherein said circuit breaker is user resettable if the circuit breaker has been tripped by said primary trip coil; and wherein said circuit breaker is not user resettable if the circuit breaker has been tripped by said secondary trip coil. ### Claim 2 (depends on 1) The circuit breaker of claim 1 wherein the determination is made that said circuit breaker is not operating within acceptable trip parameters upon detection of at least one of the following: an inrush current above a threshold level and an overcurrent above a threshold level. ### Claim 3 (depends on 1) The circuit breaker of claim 1 wherein the determination is made that said circuit breaker is not operating within acceptable trip parameters upon detection of at least one of the following: a ground fault condition and an arc fault condition. ### Claim 4 (depends on 1) The circuit breaker of claim 1 wherein the determination is made that said circuit breaker is not operating within acceptable disable parameters upon detection of at least one of the following: a malfunction of said primary trip coil and a malfunction within said monitoring circuit. ### Claim 5 (depends on 1) The circuit breaker of claim 1 wherein said secondary trip coil is activated in the event that said monitoring circuit becomes inoperable. ### Claim 6 (depends on 1) The circuit breaker of claim 1 further comprising: a normally closed relay having a relay activating circuit and a switching circuit, the switching circuit defaulting to an on state, but being switchable to an off state when activating power is supplied to the relay activating circuit, the switching circuit automatically returning to the on state when activating power to the relay activating circuit is interrupted; wherein the switching circuit of said normally closed relay is electrically connected to said secondary trip coil, such that the switching circuit of said normally closed relay provides power to said secondary trip coil when the switching circuit is in the on state, thereby causing activation of said secondary trip coil and tripping of the circuit breaker, but does not provide power to said secondary trip coil when the switching circuit is in the off state; and wherein said monitoring circuit is electrically connected to the relay activating circuit of the normally closed relay, said monitoring circuit supplying activating power to the relay activating circuit so long as a determination is made that said circuit breaker is operating within acceptable disable parameters, and ceasing to supply activating power to the relay activating circuit, thereby tripping said circuit breaker, when either (i) said monitoring circuit determines that said circuit breaker is not operating within the acceptable disable parameters, or (ii) said monitoring circuit becomes inoperable. ### Claim 7 (depends on 6) The circuit breaker of claim 6 wherein said monitoring circuit is electrically connected to said primary trip coil, and wherein said monitoring circuit provides power to said primary trip coil when a determination is made that said circuit breaker is not operating within acceptable trip parameters, thereby causing activation of said primary trip coil and tripping of the circuit breaker. ### Claim 8 (depends on 6) The circuit breaker of claim 6 wherein an input of the switching circuit of said normally closed relay receives power from the main power circuit, downstream of said pair of main contacts, and an output of the switching circuit of said normally closed relay is electrically connected to said secondary trip coil. ### Claim 9 (depends on 8) The circuit breaker of claim 8 wherein said secondary trip coil requires greater power to trip than said secondary trip coil momentarily experiences prior to the switching circuit of the normally-closed relay being switched to its open state when the breaker is either switched to its closed state or when the breaker is first provided power while it is already in an unpowered, closed state. ### Claim 10 (depends on 8) The circuit breaker of claim 8 further comprising a capacitive delay circuit electrically connected in the switching circuit of said normally closed relay. ### Claim 11 (depends on 6) The circuit breaker of claim 6 wherein said normally closed relay comprises a solid state normally closed relay and wherein the relay activating circuit comprises a solid state activating circuit. ### Claim 12 (depends on 6) The circuit breaker of claim 6 wherein said normally closed relay comprises an electro-mechanical normally closed relay and wherein the relay activating circuit comprises an activating coil. ### Claim 13 (depends on 1) The circuit breaker of claim 1 further comprising a sensor electrically disposed in said main power circuit and wherein said monitoring circuit is in electrical communication with said sensor. ### Claim 14 A circuit breaker comprising: a pair of main contacts movable with respect to each other between a closed position wherein a line terminal and a load terminal are in electrical communication with each other via a main power circuit, and an open position wherein the line terminal and the load terminal are electrically isolated from each other; a primary trip coil operably connected to at least one of said pair of main contacts, said primary trip coil being adapted, upon activation, to cause said pair of main contacts to move from the closed position to the open position, thereby tripping said circuit breaker; a secondary trip coil operably connected to at least one of said pair of main contacts, said secondary trip coil being adapted, upon activation, to cause said pair of main contacts to move from the closed position to the open position, thereby tripping said circuit breaker; a monitoring circuit monitoring operation of the circuit breaker; said monitoring circuit being electrically connected to said primary trip coil such that said monitoring circuit provides power to said primary trip coil when a determination is made that said circuit breaker is not operating within acceptable trip parameters, thereby causing activation of said primary trip coil and tripping of the circuit breaker; a normally closed relay having a relay activating circuit and a switching circuit, the switching circuit defaulting to an on state, but being switchable to an off state when activating power is supplied to the relay activating circuit, the switching circuit automatically returning to the on state when activating power to the relay activating circuit is interrupted; wherein the switching circuit of said normally closed relay is electrically connected to said secondary trip coil, such that the switching circuit of said normally closed relay provides power to said secondary trip coil when the switching circuit is in the on state, thereby causing activation of said secondary trip coil and tripping of the circuit breaker, but does not provide power to said secondary trip coil when the switching circuit is in the off state; and wherein said monitoring circuit is electrically connected to the relay activating circuit of the normally closed relay, said monitoring circuit supplying activating power to the relay activating circuit so long as a determination is made that said circuit breaker is operating within acceptable disable parameters, and ceasing to supply activating power to the relay activating circuit, thereby tripping said circuit breaker, when either (i) said monitoring circuit determines that said circuit breaker is not operating within the acceptable disable parameters, or (ii) said monitoring circuit becomes inoperable. ### Claim 15 (depends on 14) The circuit breaker of claim 14 wherein said circuit breaker is user resettable if the circuit breaker has been tripped by said primary trip coil, and wherein said circuit breaker is not user resettable if the circuit breaker has been tripped by said secondary trip coil. ### Claim 16 (depends on 14) The circuit breaker of claim 14 wherein an input of the switching circuit of said normally closed relay receives power from the main power circuit, downstream of said pair of main contacts, and an output of the switching circuit of said normally closed relay is electrically connected to said secondary trip coil. ### Claim 17 (depends on 16) The circuit breaker of claim 16 wherein said secondary trip coil requires greater power to trip than said secondary trip coil momentarily experiences prior to the switching circuit of the normally-closed relay being switched to its open state when the breaker is either switched to its closed state or when the breaker is first provided power while it is already in an unpowered, closed state. ### Claim 18 (depends on 16) The circuit breaker of claim 16 further comprising a capacitive delay circuit electrically connected in the switching circuit of said normally closed relay. ### Claim 19 (depends on 14) The circuit breaker of claim 14 further comprising a sensor electrically disposed in said main power circuit and wherein said monitoring circuit is in electrical communication with said sensor. ### Claim 20 (depends on 14) The circuit breaker of claim 14 wherein said normally closed relay comprises a solid state normally closed relay and wherein the relay activating circuit comprises a solid state activating circuit. ### Claim 21 (depends on 14) The circuit breaker of claim 14 wherein said normally closed relay comprises an electro-mechanical normally closed relay and wherein the relay activating circuit comprises an activating coil. ### Claim 22 (depends on 14) The circuit breaker of claim 14 wherein the determination is made that said circuit breaker is not operating within acceptable trip parameters upon detection of at least one of the following: an inrush current above a threshold level and an overcurrent above a threshold level. ### Claim 23 (depends on 14) The circuit breaker of claim 14 wherein the determination is made that said circuit breaker is not operating within acceptable trip parameters upon detection of at least one of the following: a ground fault condition and an arc fault condition. ### Claim 24 (depends on 14) The circuit breaker of claim 14 wherein the determination is made that said circuit breaker is not operating within acceptable disable parameters upon detection of at least one of the following: a malfunction of said primary trip coil and a malfunction within said monitoring circuit.