# US 12,003,088 B2 · Devices for overvoltage, overcurrent and arc flash protection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,088 B2 - Document ID: US12003088B2 - Status: Granted - Kind: B2 - Application number: 18/050,265 - Filed: 2022-10-27 - Published: 2023-05-11 - Granted: 2024-06-04 - Earliest claimed: 2015-03-19 - Assignees: Ripd IP Development Ltd - Applicants: Ripd IP Development Ltd - Inventors: Zafiris G. Politis; Grigoris Kostakis; Thomas Tsovilis; Kostas Bakatsias - Web page: https://patentgrep.com/patent/US12003088B2 ## CPC - H02H 3/00: Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection (specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems H02H7/00; systems for change-over to standby supply H02J9/00 ){; integrated protection (for motors H02H7/0822)} - H02H 1/0015: {Using arc detectors} - H02H 3/08: responsive to excess current (responsive to abnormal temperature caused by excess current H02H5/04) - H02H 9/02: responsive to excess current {(current limitation for voltage regulators G05F1/573; disconnection after limiting H02H3/025)} - H02H 9/041: {using a short-circuiting device} - H02H 3/023: {by short-circuiting} - 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 crowbar module includes first and second electrical terminals, a module housing, and first and second crowbar units. The first crowbar unit is disposed in the module housing and includes a first thyristor electrically connected between the first and second electrical terminals. The second crowbar unit is disposed in the module housing and includes a second thyristor electrically connected between the first and second electrical terminals in electrical parallel with the first crowbar unit. ## Claims ### Claim 1 A surge protection system comprising: a crowbar device that is coupled to and between a plurality of phase lines and is configured to prevent an overvoltage condition by selectively generating a low resistance current path between the plurality of phase lines; a plurality of surge protection devices that are connected to respective ones of the plurality of phase lines and to the crowbar device and that are configured to protect the equipment during an overvoltage condition by conducting a limited amount of current that corresponds to the overvoltage condition; and an external trigger and alarm interface circuit electrically connected to the crowbar device. ### Claim 2 (depends on 1) The surge protection system according to claim 1, wherein ones of the plurality of surge protection devices each comprise: a first terminal that is connected to a corresponding one of the plurality of phase lines; and a second terminal that is connected to the crowbar device, wherein the crowbar device comprises: a plurality of phase terminals that are connected to the plurality of surge protection devices; and a plurality of thyristors that are connected between different pairs of the phase terminals. ### Claim 3 (depends on 2) The surge protection system according to claim 2, wherein the crowbar device further comprises a crowbar trigger circuit that is operable to generate thyristor trigger signals to the plurality of thyristors responsive to detecting a fault condition on the phase lines. ### Claim 4 (depends on 3) The surge protection system according to claim 3, wherein the crowbar trigger circuit comprises: a rectification circuit that generates a direct current (DC) signal corresponding to voltages between the plurality of phase lines; a comparator that compares the DC signal from the rectification circuit to a reference signal; and a plurality of isolation drivers that receive a comparator output, and, responsive to the comparator output indicating that the DC signal exceeds the reference signal, generates a trigger signal that turns on the plurality of thyristors. ### Claim 5 (depends on 1) The surge protection system according to claim 1, wherein the surge protection devices comprise metal oxide varistors. ### Claim 6 (depends on 2) The surge protection system of claim 2, further comprising: a plurality of snubber circuits electrically connected in parallel with the plurality of thyristors, respectively, between the different pairs of the phase terminals. ### Claim 7 (depends on 6) The surge protection system of claim 6, further comprising: a plurality of inductors electrically connected in series with the parallel combinations of the plurality of thyristors and the plurality of snubber circuits, respectively, between the different pairs of the phase terminals. ### Claim 8 (depends on 7) The surge protection system of claim 7, wherein each of the plurality of inductors comprises: an electrically conductive coil member, the coil member including a spirally extending coil strip defining a spiral coil channel; and an electrically insulating casing including a separator wall portion that fills the coil channel. ### Claim 9 (depends on 1) The surge protection system of claim 1, further comprising: a housing that includes a cover defining an enclosed cavity; wherein the crowbar device and the plurality of surge protection devices are within the housing; and wherein the housing includes a filler material that at least partially fills a volume enclosed cavity not occupied by the crowbar device and the plurality of surge protection devices. ### Claim 10 (depends on 1) The surge protection system of claim 1, wherein the crowbar device is electrically connected to an external current sensor. ### Claim 11 A crowbar system comprising: a crowbar module including: a module housing; a thyristor disposed in the module housing; a coil disposed in the module housing; a trigger circuit disposed in the module housing; and a snubber circuit disposed in the module housing; and an external trigger and alarm interface circuit electrically connected to the crowbar module. ### Claim 12 (depends on 11) The crowbar system of claim 11, wherein the crowbar module is coupled to and between a plurality of phase lines and is configured to prevent an overvoltage condition by selectively generating a low resistance current path between the plurality of phase lines. ### Claim 13 (depends on 12) The crowbar system of claim 12, wherein the thyristor is connected between a pair of the plurality of phase lines. ### Claim 14 (depends on 12) The crowbar system of claim 12, wherein the trigger circuit is configured to generate a thyristor trigger signal responsive to detecting a fault condition on the pair of the plurality of phase lines, the thyristor being responsive to the thyristor trigger signal. ### Claim 15 (depends on 12) The crowbar system of claim 12, wherein the trigger circuit comprises: a rectification circuit that generates a direct current (DC) signal corresponding to voltages between the plurality of phase lines; a comparator that compares the DC signal from the rectification circuit to a reference signal; and a plurality of isolation drivers that receive a comparator output, and, responsive to the comparator output indicating that the DC signal exceeds the reference signal, generates a trigger signal that turns on the plurality of thyristors. ### Claim 16 (depends on 11) The crowbar system of claim 11, wherein the crowbar module is electrically connected to an external current sensor. ### Claim 17 (depends on 11) The crowbar system of claim 11, wherein the external trigger and alarm interface circuit is configured to provide a connection between the trigger circuit and a monitoring location. ### Claim 18 (depends on 17) The crowbar system of claim 17, further comprising: a microcontroller connected between the trigger circuit and the external trigger and alarm interface circuit; wherein the microcontroller is configured to send an alarm signal and/or supervisory control and data acquisition (SCADA) information to the monitoring location. ### Claim 19 (depends on 18) The crowbar system of claim 18, wherein the monitoring location comprises a remote visual and/or audible annunciator. ### Claim 20 A surge protection system comprising: a crowbar device that is coupled to and between a plurality of phase lines and is configured to prevent an overvoltage condition by selectively generating a low resistance current path between the plurality of phase lines; and a plurality of surge protection devices that are connected to respective ones of the plurality of phase lines and to the crowbar device and that are configured to protect the equipment during an overvoltage condition by conducting a limited amount of current that corresponds to the overvoltage condition; wherein ones of the plurality of surge protection devices each comprise: a first terminal that is connected to a corresponding one of the plurality of phase lines; and a second terminal that is connected to the crowbar device, wherein the crowbar device comprises: a plurality of phase terminals that are connected to the plurality of surge protection devices; and a plurality of thyristors that are connected between different pairs of the phase terminals; wherein the crowbar device further comprises a crowbar trigger circuit that is operable to generate thyristor trigger signals to the plurality of thyristors responsive to detecting a fault condition on the phase lines; and wherein the crowbar trigger circuit comprises: a rectification circuit that generates a direct current (DC) signal corresponding to voltages between the plurality of phase lines; a comparator that compares the DC signal from the rectification circuit to a reference signal; and a plurality of isolation drivers that receive a comparator output, and, responsive to the comparator output indicating that the DC signal exceeds the reference signal, generates a trigger signal that turns on the plurality of thyristors.