Electrical device with pressure sensor

Abstract

An improved electrical device includes a hermetically-sealed volume and a pressure sensor disposed in the hermetically-sealed volume. The pressure sensor is disposed to determine a pressure change in the volume. The pressure change may correspond to a loss of hermeticity. In response to the pressure change, the electrical device may be determined to be defective or otherwise identified for replacement.

Description

ELECTRICAL DEVICE WITH PRESSURE SENSORCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority of US Provisional Application No. 63 / 554,833, entitled “Electrical Device with Pressure Sensor,” filed on February 16, 2024, the entirety of which is hereby incorporated by reference.FIELD OF THE TECHNOLOGY

[0002] The subject disclosure relates to electrical switching devices, such as contactor devices and electrical fuse devices, and more particularly to improved contactor devices with improved safety outcomes.BACKGROUND OF TECHNOLOGY

[0003] Many conventional devices are known to selectively power on or off electrical devices. For example, electrical contactors, e.g., high-voltage DC contactors, and fuses, e.g., electrical fuses and / or pyrotechnic fuses, are conventionally available and used in electrical systems. Contactors may be configured to interrupt or complete a circuit to control electrical power to and from a device. Fuses may be used for overcurrent protection. For example, fuses may be used to prevent short circuits, overloading, and / or permanent damage to an electrical system or a connected electrical device.

[0004] Many electrical devices such as those just described include an enclosed volume in which various components are maintained. In some examples, the volume may be hermetically sealed. However, in some instances, e.g., when a seal becomes compromised, hermeticity can also be compromised. Operating the device in the absence of hermeticity may be undesirable.

[0005] Accordingly, there is a need in the art for improved switching devices, interrupter devices, and / or the like, which are capable of determining when their functionality and / or safety is compromised.SUMMARY OF THE TECHNOLOGY

[0006] The subject technology relates to improved electrical devices and methods of making and using those devices. In examples, aspects of this disclosure relate to improved switching devices with an integrated pressure sensor used to monitor a pressure in a volume, such as a hermetically sealed volume. Aspects of this disclosure can also relate to improved techniques for identifying compromised electrical devices.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] So that those having ordinary skill in the art to which the disclosed systems and techniques pertain will more readily understand how to make and use the same, reference may be had to the following drawings.

[0008] FIG. 1 is a cross-sectional view of an electrical device, in accordance with aspects of this disclosure.

[0009] FIG. 2 is a schematic block diagram illustrating aspects of a compromised device detection system, in accordance with aspects of this disclosure.

[0010] FIG. 3 is a flow chart showing an example method of determining a compromised electric device, in accordance with aspects of this disclosure.DETAILED DESCRIPTION

[0011] The subject technology overcomes many of the prior art problems associated with electrical devices. In brief summary, the subject technology provides improved electrical devices including acontactor design that includes a pressure sensor in a sealed volume of the contactor. For example, aspects of this disclosure can be used to detect a loss of hermeticity in an electrical device.

[0012] Without limitation, the devices and techniques described herein may provide improved electrical devices, which may be less complex, may be cheaper to manufacture and / or use, and / or that may have improved safety and / or result in improved system protection, when compared to similar conventional systems. Moreover, while aspects of this disclosure may be particularly useful in certain application, like high voltage automotive systems, the systems and techniques described herein may be useful with many electrical systems.

[0013] Aspects of the disclosure will now be explained in more detail with reference to the Figures.

[0014] FIG. 1 is a cross-sectional view of an electrical device 100. The electrical device 100 of FIG. 1 is for example only. The electrical device may be any electrical device that has a hermetically sealed or otherwise pressure controlled volume, for example.

[0015] Specifically, FIG. 1 shows a device 100 including a housing 102. The housing 102 is generally illustrated as including a number of housing members, including an upper housing member 104, a lower housing member 106, and a housing base 108 disposed between the upper housing member 104 and the lower housing member 106. The construction of the housing 102 is intended to be for example only. Other types and arrangements of housings may be conventional in the art, and aspects of this disclosure may be used with other housings.

[0016] At least a portion of the housing 102 defines an interior space or a volume 110. In the illustrated example, the volume 110 may include only a portion of an interior of the upper housing member 104. In other examples, however, the volume 110 may extend into both of the upper housing member 104 and the lower housing member 106 and / or may be defined only by the lower housing member 106.

[0017] In examples of this disclosure, the volume 110 is a pressure-controlled environment, such as a hermetically sealed volume. For example, during manufacture of the device 100, the volume 110 may be evacuated and replaced or backfilled with a pressurized gas, e.g., a pressurized inert gas. In other examples, the volume 110 may be backfilled with a different gas and / or combination of gasses. In some conventional devices, a port or conduit (not shown) may provide access to the volume 110 to facilitate creation of the pressure controlled environment.

[0018] Although not explicitly identified in FIG. 1, the housing 102 may have a number of mechanical interfaces that cooperate, e.g., with each other and / or with components of the housing 102, to maintain the pressure-controlled environment. For examples, such interfaces may be formed by seals, gaskets, epoxies, and / or the like. Should any of these seals fail the pressure-controlled environment is compromised. For example, hermeticity can be lost. In such instances, the device should no longer be used. Aspects of this disclosure relate to determining when a seal is broken, e.g., to identify when the electrical device 100 may be faulty and should be repaired and / or replaced.

[0019] The electrical device 100 includes two fixed contacts 112. The fixed contacts 112 extend partially into the volume 110. The fixed contacts 112 also are accessible from a position outside the electrical device 100, e.g., for connection to a power source and a load (not shown).

[0020] The electrical device 100 also includes a movable contact 114 disposed in the volume 110. The movable contact 114 is configured to move relative to the fixed contacts 112, e.g., between a first position spaced from the fixed contacts 112 (which may be the position shown in FIG. 1) and a second position contacting the fixed contacts. The first position may be an open position, in which electrical power does not flow between the fixed contacts 112. Specifically, when the movable contact is in the first position, the two fixed contacts 112 are electrically insulated from each other. The second position may be a closed position, e.g., in which electrical power flows between the fixed contacts 112. For instance, in the secondposition, the movable contact 114 contacts both of the fixed contacts 112 to function as an electrical conduit between them.

[0021] In the illustrated example, the movable contact 114 is associated with an actuator subassembly 116 configured to, among other functions, facilitate selective opening and closing of the switch, e.g., by facilitating selective movement of the movable contact 114 into and out of contact with the fixed contacts 112, as discussed above. For example, the actuator subassembly 116 is illustrated as including a shaft 118 and a core or coil 120, e.g., a DC coil, which may be selectively energized to cause a portion of the actuator assembly, e.g., the shaft 118 and an associated plunger 122, to move up and down, causing the movable contact 114 to accordingly move relative to the fixed contacts 112. The illustrated electrical device 100, including the illustrated actuator subassembly 116, is for example only. As noted above, aspects of this disclosure can be used with any electrical device having a pressure-controlled volume.

[0022] The device 100 also is illustrated as including a pyrotechnic actuator 124. In conventional use, the pyrotechnic actuator 124 may be configured to detonate, e.g., in response to an event such as a surge, short-circuit, or the like. In examples, the pyrotechnic element may include a squib or detonator 126 and a projectile 128. When the detonator 126 is activated (or detonated), the projectile 128 is driven (e.g., downward in the orientation of FIG. 1) in a manner that forces the movable contact 114 away from the fixed contacts 112. For example, in the illustrated example, the projectile 128 is forced into the actuator assembly 116, for instance, into a top of the shaft 118, to drive the movable contact 114 away from the fixed contacts 112, e.g., to drive the movable contact 114 toward an open position and inhibit flow of electricity through the electrical device 100.

[0023] As noted above, the volume 110 is a hermetically sealed volume. When the volume 110 is hermetically sealed, an internal pressure of the volume 110 is generally higher than atmospheric pressure. For example, the backfilling operation used to create the hermetic environment may include injectingpressurized air into the volume 110 to a predetermined pressure, e.g., a predetermined pressure that is higher than the atmospheric pressure.

[0024] Aspects of this disclosure include placing a pressure sensor 130 in the volume 110 to monitor the pressure in the volume 110. For example, the pressure sensor 130 may be any sensor that is configured to generate pressure data associated with the volume 110. For example, the pressure sensor 130 may be a pressure transducer, e.g., embodied as a switch or sensor. In other examples, the pressure sensor 130 may be a piezoelectric pressure sensor, such as a piezo resistive bridge or a piezoresi stive element. Other types of pressure sensors, including but not limited to microelectromechanical systems (MEMS) pressure sensors, capacitive pressure sensors, and / or integrated circuit-based pressure sensors. In examples, the pressure sensor 130 may be disposed on a stationary or fixed surface for monitoring the pressure in the volume 110. In other examples, the pressure sensor 130 can be at least partially disposed outside the volume and include a sensing element disposed in communication with the volume 110.

[0025] The pressure sensor 130 can be configured to monitor the pressure of the volume 110 continuously, intermittently, e.g., at a predetermined time interval, on demand, randomly, and / or at other times. For example, the pressure sensor 130 may be configured to determine pressure information during the functional life of the device. The pressure sensor 130 may also (or alternatively) be used to assess functionality of the device, e.g., at the time of manufacture of the device, at a time of integration of the device into a system, or the like. In some examples, the techniques described herein may be implemented to replace conventional leak testing, e g., undertaken during end of line testing.

[0026] The pressure sensor 130 is configured to generate pressure data 132. The pressure data 132 may be a pressure measurement, e.g., an absolute pressure or a gauge pressure, a differential pressure measurement, a change in pressure, data from which a pressure or pressure change may be determined,and / or any other data generated by the pressure sensor 130 and associated with the pressure in the volume 110.

[0027] As also illustrated in FIG. 1, the pressure sensor 130 is in communication with a control system 134. The control system 134 may be configured to receive the pressure data 132. The control system 134 can be implemented as one or more controllers, microcontrollers, computing devices, and / or any other control system. The control system 134 is illustrated schematically as being outside the housing 102. In such examples, the control system 134 can be configured to receive the pressure data 132 via one or more communication connections. For example, such connections may be wired or wireless. In other examples, the control system 134 may be disposed in the volume 110. For example, the control system 134 may comprise a circuit board, e.g., a printed circuit board, disposed in the volume 110. In such examples, the pressure sensor 130 may be disposed on the circuit board and connected to other elements for performing the functions of the control system 134.

[0028] In examples, the control system 134 can include functionality to receive the pressure data 132 and / or to process the pressure data 132. For example, the control system 134 can include functionality to determine whether the device 100 (and specifically the volume 110) is experiencing an anomalous event. For example, should a seal become broken or worn, the volume 110 may lose hermeticity. This loss of hermeticity may be indicated by a drop in pressure. Specifically, should a seal become defective, a pressure in the volume 110 may drop, e.g., to correspond to an ambient pressure. The control system 134 may be configured to identify this change in pressure, e.g., based on the received pressure data 132.

[0029] In some examples, the control system 134 can determine, from the pressure data 132, a pressure in the volume 110. The control system 134 can also include functionality to compare the pressure data 132 to a threshold pressure, e.g., to determine whether the measured pressure is equal to or below the threshold pressure. In examples, the threshold pressure may correspond to a pressure higher than anatmospheric or ambient pressure. In these examples, should the measured pressure be equal to or below the threshold temperature, the measured pressure may signify an anomalous pressure within the volume 110. That is, the control system 134 can determine an anomalous condition in response to determining that a measured pressure is equal to or below a threshold pressure.

[0030] In other examples, the control system 134 can determine, from the pressure data 132, a change in pressure in the volume 110. The control system 134 can also include functionality to compare the change in pressure value to a threshold change. For example, if a measured change in pressure is equal to or greater than a threshold change, the control system 134 can determine an anomalous condition.

[0031] The control system 134 can also be configured to generate control data 136. For example, the control data 136 can include one or more control signals for controlling one or more aspects of the device 100. For example, the control data 136 may cause the electrical device 100 to actuate the movable contact 114 away from the fixed contacts 112, e.g., to force the device 100 open. In one example, the control data 136 can cause the coil 120 to be energized / deenergized in a manner that moves the shaft 118 to the open position. In another example, the control data 136 can cause the pyrotechnic element 124 (or some other fuse device) to detonate, e.g., to force the device 100 into an open position and prevent the device from closing.

[0032] FIG. 1 also illustrates a retention mechanism 138 disposed in the volume 110. The retention mechanism 138 generally includes a base plate 140 and a plurality of contact retention members 142. The base plate 140 may be disposed on the housing base plate 108. In the illustrated example, the base plate 140 may include a flanged protrusion 144 configured for receipt in an opening (e.g., a central opening) in the housing base plate 108. The flanged protrusion 144 may position the retention mechanism 138 relative to the housing base plate 108 and / or facilitate coupling of the two components, e.g., via a press-fit or the like.

[0033] As also illustrated in FIG. 1, the retention mechanism 138 can include a score 146 proximate the flanged protrusion 144. For example, the score 146 is a circular score formed in a top of the base plate 140, generally concentric with the flanged protrusion 144. The score 146 may facilitate separation of the portion of the base plate 140 including the flanged protrusion 144 from the remainder of the base plate 140. For example, in instances in which the pyrotechnic actuator 124 is detonated, a portion of the actuator assembly 116 may be driven into the base plate 140 with sufficient force to cause the base plate to fail at the score 146. For example, this failure of the base plate 140 may facilitate a longer length of travel of the shaft 118, when compared with normal operation. This longer travel may cause the movable contact 114 to engage (and be retained by) the retention mechanism 138.

[0034] The score 146 is shown for example only. Other methods of weakening a portion of the base plate 140, including perforations, non-circular thinned regions, and / or other frangible profiles may be used to facilitate separation of the portion of the base plate 140. In other examples, however, the base plate 140 may not be configured to separate. For example, the retention mechanism 138 may be positioned relative to the movable contact 114 such that the movable contact 114 may be retained by the retention mechanism without destruction of the base plate 140.

[0035] The contact retention members 142 are configured to facilitate retention of the movable contact 114 at a position spaced from the fixed contacts 112, e.g., in an open position. In the illustrated example, the contact retention members 142 comprise one or more tabs 148 (three of which are illustrated) or protrusions having distal ends in a path of travel of the movable contact 114. The protrusions or tabs are angled, e.g. relative to a travel path (the vertical direction in the example) and resilient. For example, the retention members 142 are configured to allow one-way travel of the movable contact 114, e.g., in a first (downward) direction, but to inhibit or prevent motion of the movable contact 114 in the opposite (e.g., upward) direction. In examples, the movement of the movable contact 114 resulting from contact by theprojectile 128 is sufficient such that the movable contact 114 pushes the tabs 148 out of the travel path (e.g., laterally in the illustrated orientation as a result of contact with the angled surface of the tabs 148) until the movable contact 114 clears the distal ends of the retention members 142. Once the movable contact 112 clears the retention members 142, the retention members 142 are no longer contacted by the movable contact 112. Without the force applied by the movable contact 112 to the tabs 148, the retention members 142 “spring” back to their angled positions (the position illustrated in FIG. 1), with the distal ends of the tabs 148 being disposed above (e g., over) a top surface of the movable contact 114. With the distal ends of the retention members 142 over the movable contact 112, the retention members 142 inhibit upward motion (in the orientation of FIG. 1).

[0036] In non-limiting examples, the retention mechanism 138 may be a molded part, e.g., injection molded or the like from a rigid polymer. The retention members 142 are illustrated as being supported on the base plate 140, e.g., by one or more support legs 150. This is for example only. More specifically, the support legs 150 may be substantially vertical, and the tabs 148 of the retention members 142 extend from a position proximate a top of the support legs 150, in an angled manner to space the distal end of the retention member 142 from the support leg 150, e.g. in the horizontal direction and relatively lower. As noted above, the distal end of the tabs 148 is disposed in a path of travel of the movable contact 114. The support leg 150 is spaced from the travel path, e.g., so as to not impede travel of the movable contact 114. In examples, the support leg 150 is substantially rigid, with the tab 148 of the retention member 142 being movable relative to the support leg 150. For example, the tab 148 of the retention member 142 can pivot relative to the support leg 150 about a portion (obscured in FIG. 1) connecting the tab 148 of the retention member 142 and the support leg 150. Such a portion may function as a pivot or hinge, e.g., a “living hinge.” During pivoting, the retention member 142 may pivot into a void 152 associated with the support leg 150.

[0037] Of course, the contact retention mechanism 142 is for example and may be one example of a lockout feature. Modifications and alternative configurations also are contemplated. For example, other configurations that allow for movement of the movable contact 114 to a position spaced from the fixed contacts 112, and that can retain the movable contact 114 in such a spaced position may be used. In one non-limiting example, the retention members 142 may be replaced with detents or spring-biased members that are biased into a position blocking upward movement of the movable contact 114 when the movable contact travels a predetermined distance from the fixed contacts 112. In still further examples, one or more posts may extend upward from the base plate 140, e.g., in a footprint of the movable contact 114. In this example, a bottom of the movable contact 114 may have corresponding openings or bores that align with the posts, such that when the movable contact 114 is forced into contact with the posts, the posts cooperate with the openings to retain the movable contact 114. For example, the posts may form an interference fit with the openings. In other examples, the posts may have a contour that expands or otherwise deforms to create a force that retains the movable contact 114 in a position spaced from the fixed contacts 112.

[0038] In the context of this disclosure, the control system 134 may receive and / or monitor the pressure data 132. In response to an anomalous pressure reading, e.g., in response to determining that a seal likely has malfunctioned, the control system 134 may generate the control data 136 that cause the pyrotechnic actuator 124 to detonate. This detonation sends the projectile 128 into the shaft 118, driving the movable contact 114 away from the fixed contacts 112. The movable contact 114 may be driven sufficiently far that the retention mechanism 138 retains, locks, or otherwise inhibits movement of the movable contact 114 toward the fixed contacts 112. In other examples, the control system 134 may generate, in response to a determined pressure anomaly, the control data 136 that causes the coil 120 to move the movable contact 114 away from the fixed contacts 112.

[0039] FIG. 2 is a schematic diagram illustrating additional aspects of this disclosure. More specifically, FIG. 2 schematically illustrates the control system 134 in communication with the pressure sensor 130 and also in communication with a solenoid driver 202 and a regulator 204. The solenoid driver 202 may represent any actuator or actuator assembly that can force the contactor into an open state. As detailed herein, based on a drop in pressure measured by the pressure sensor, the control system 134 can cause opening of the contactor device (e.g., to disable the device from further use). In some examples, the solenoid driver 202 may be the coil 120 and / or the pyrotechnic actuator 124.

[0040] The regulator 204 may be configured to regulate a pressure associated with the electrical device. For example, aspects of this disclosure may be useful during creation of a hermetic environment / seal. For instance, the pressure sensor 130 can be used to monitor a pressure in the volume 110 of the contactor during backfilling of the volume 110. The regulator 204 may be configured to allow / disallow continued (back)filling of the volume 110, e.g., until a desired pressure is reached. Thus, and as will be appreciated, the pressure sensor 130 disposed in the volume 110 may be used while the electrical device 100 is in use and / or during manufacturing, including when a hermetic seal or other pressurized environment is established. Regarding the former, the systems and techniques described herein may be useful to identify electrical devices that are no longer functioning properly, e.g., that have lost hermeticity. Regarding the latter, the systems and techniques described herein may be useful to ensure that a device has been fabricated properly, e.g., without leaks.

[0041] FIG. 3 is a flowchart showings aspects of a process 300, which may be a process to identify a compromised electrical device, like the electrical device 100.

[0042] At an operation 302, the process 300 includes providing an electrical device with a pressure sensor disposed in a volume. For example, the electrical device may be the electrical device 100 discussed above. For example, the electrical device can include the volume 110 and the pressure sensor 130 disposedin the volume 110. Without limitation, the volume 110 may be a pressure-controlled volume, e.g., a hermetically sealed volume.

[0043] At an operation 304, the process 300 includes monitor pressure data generated by the pressure sensor. For example, the pressure data may be the pressure data 132 discussed above. For instance, the pressure data can be absolute pressure data, relative pressure data, differential pressure data, gauge pressure data, and / or any other pressure-related information associated with the interior volume of the electrical device.

[0044] At an operation 306, the process 300 includes determining, from the pressure data, an anomalous pressure. For example, the pressure data 132 generated by the pressure sensor 130 may indicate that a pressure in the volume 110 has been reduced to an ambient or atmospheric pressure. In such an instance, the electrical device may be compromised, e.g., because the lower pressure indicates that the device is no longer sealed.

[0045] At an operation 308, the process 300 includes configuring, in response to the anomalous pressure, the electrical device in an open position. For example, and as detailed further above, aspects of this disclosure can include the movable contact 114 that is movable relative to the fixed contacts 112. The operation 308 can include controlling the movable contact 114 to move to a position away from the fixed contacts 112, e.g., to electrically insulate the fixed contacts 112 from each other. For example, the operation 308 can include controlling the coil 120 to move the movable contact 114 using the actuator assembly 116. In other examples, the operation 308 can include detonating the pyrotechnic element 124.

[0046] In still further aspects of this disclosure, the operation 308 and / or an additional operation may include generating and / or transmitting a signal to indicate that the electrical device 100 is compromised. For instance, when the electrical device is used in an electrical system, such as an autonomous vehicle orthe like, the anomalous pressure may be signaled to a user, driver, technician, fleet operator, and / or some other party.

[0047] As will be appreciated from this disclosure, some conventional electrical devices, e.g., contactors, are hermetically sealed. These devices may include one or more interfaces that maintain an integrity of the seal, e g., that maintain hermeticity. In these devices, the internal volume may be a higher pressure than an atmosphere of the device. Accordingly, aspects of this disclosure include monitoring the internal volume, e.g., using a pressure sensor, to determine whether the pressure in the environment has reduced. In these instances, the device may be replaced or repaired, e.g., to restore the hermetically sealed environment. In some examples, the electrical device may be controlled to open the device and to retain the device in the open state. In this way, a contactor with failed hermeticity will not be able to close its contacts if the correct pressure is not measured, e g., at power up, manufacture, during use, and / or at any other time.

[0048] While the subject technology has been described with respect to preferred embodiments, those skilled in the art will readily appreciate that various changes and / or modifications can be made to the subject technology without departing from the spirit or scope of the subject technology. For example, each claim may depend from any or all claims in a multiple dependent manner even though such has not been originally claimed.

Claims

WHAT IS CLAIMED IS:

1. A switching device comprising: a housing defining a volume, the volume being a hermetically sealed volume; fixed contacts extending at least partially into the volume; a movable contact disposed in the volume and movable between a first position spaced from the fixed contacts and a second position contacting the fixed contacts; and a pressure sensor disposed in the volume and configured to generate pressure data associated with a pressure in the volume, wherein the switching device is configured to, based on a change in the pressure in the volume determined from the pressure data, move the movable contact toward the first position.

2. The switching device of claim 1, further comprising: an actuator assembly configured to move the movable contact between the first position and the second position, wherein the actuator assembly is configured to move the movable contact from the second position toward the first position based on the change in the pressure in the volume.

3. The switching device of claim 1 or claim 2, further comprising a control system configured to receive the pressure data generated by the pressure sensor and determine the change in the pressure.

4. The switching device of claim 3, wherein the control system is further configured to: determine whether the pressure in the volume is equal to or less than a threshold pressure; andin response to the pressure being equal to or less than the threshold pressure, cause the movable contact to be moved away from the second position.

5. The switching device of any one of claim 1 through claim 4, further comprising: a pyrotechnic element operatively coupled to the pressure sensor, wherein the pyrotechnic element is configured to move the movable contact from the second position toward the first position based on the change in the pressure in the volume.

6. The switching device of any one of claim 3 through claim 5, wherein the control system is disposed outside the volume, and the pressure sensor is configured to communicate with the control system.

7. The switching device of any one of claim 1 through claim 6, further comprising a contact retention member configured to retain the movable contact in a third position spaced from the fixed contacts.

8. The switching device of claim 7, wherein the contact retention member comprises one or more flexible members configured to allow movement of the movable contact in a first direction away from the fixed contacts and to inhibit movement of the movable contact in a second direction toward the fixed contacts.

9. The switching device of any one of claim 1 through claim 8, wherein the pressure sensor comprises a piezoelectric pressure sensor.

10. The switching device of any one of claim 1 through claim 9, further comprising a circuit board, wherein the pressure sensor is disposed on the circuit board.

11. The switching device of any one of claim 1 through claim 10, wherein the pressure sensor monitors the pressure of the volume during use of the switching device.

12. The switching device of claim 1 through claim 11, wherein the pressure sensor monitors the pressure of the volume during hermetically sealing the volume.

13. A method of determining an anomaly associated with an electrical switching device comprising: providing the switching device of any one of claim 1 through claim 12; monitoring the pressure sensor data generated by the pressure sensor; determining, based at least in part on the pressure sensor data, the change in pressure in the volume; and causing, in response to determining the change in pressure, the movable contact to move toward the first position.

14. The method of claim 13, wherein the causing the movable contact to move toward the first position comprises controlling an actuator assembly to move the movable contact.

15. The method of claim 13 or claim 14, wherein the causing the movable contact to move toward the first position comprises causing detonation of a pyrotechnic actuator.

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