Patent Application
20210202201
The disclosed and claimed concept relates generally to circuit interruption equipment and, more particularly, to a safety apparatus that is formed from a terminal shield having an indication circuit incorporated therein.
Numerous types of circuit interruption devices are known for use in protecting certain portions of electrical circuits from undesirable conditions such as overcurrent conditions, under-voltage conditions, and numerous other known conditions. Such circuit interruption devices are typically connected with a line conductor and a load conductor for each phase that is desired to be interruptible. Each pole that interrupts a phase typically includes a set of separable contacts that are movable between a CLOSED state, in which the line and load conductors of any given pole are electrically connected with one another, and an OPEN state in which the line and load conductors of any given pole are electrically disconnected. In a case in which a circuit interrupter includes a plurality of poles, an operating mechanism and other known equipment are employed to simultaneously move all of the poles between the CLOSED state and the OPEN state.
While such circuit interruption devices have been generally effective for their intended purposes, they have not been without limitation. For instance, even though a circuit interrupter might give a visual impression from its exterior that the sets of separable contacts are all in the OPEN state, circuit interrupters can malfunction and can potentially leave one or more poles in the CLOSED state. If it is desired that work be performed on a circuit that includes such a circuit interrupter, a failure to ascertain that a portion of the circuit remains live can potentially have disastrous consequences for a technician performing the work. Furthermore, even if the circuit interrupter has performed properly and has moved all of the sets of separable contacts to the OPEN state, one side of the circuit interrupter typically will remain connected to a number of line conductors which typically will remain electrified. As employed herein, the expression “a number of” and variations thereof shall refer broadly to any non-zero quantity, including a quantity of one. Despite knowing that one side of the circuit interrupter remains electrically connected with live, i.e., electrified, line conductors, the technician cannot always be certain which side of the circuit interrupter is the electrified side and which side is the protected side. Such a situation can become even more uncertain in situations where a circuit can be fed from two directions, such as in a grid-tied photovoltaic application. Improvements thus would be desirable.
An improved safety apparatus is in the form of a terminal shield having an indication circuit incorporated therein. The safety apparatus is usable with a circuit interrupter to overlie one or more terminals of the circuit interrupter that are connected with line and load conductors and to thereby form an improved circuit interrupter apparatus that is likewise in accordance with the disclosed and claimed concept. The safety apparatus can be employed at the line side of a circuit interrupter, at the load side of a circuit interrupter, or at both sides of a circuit interrupter. The safety apparatus can be provided as part of an improved circuit interrupter apparatus or can be provided to retrofit existing circuit interrupters. The indication circuit advantageously outputs from a top surface of the terminal shield one of a visual indication and an audible indication when one or more terminals of the circuit interrupter are electrified, thereby easily conveying to a technician the portions of the circuit interrupter that are electrified.
Accordingly, an aspect of the disclosed and claimed concept is to provide a safety apparatus in the form of a terminal shield having an indication circuit incorporated therein that is usable with a circuit interrupter having a plurality of terminals, wherein the indication circuit provides at least one of a visual indication and an audible indication when one or more of the terminals that the terminal shield overlies are electrified.
Another aspect of the disclosed and claimed concept is to provide such a safety apparatus wherein a visual indication is output from a top surface of the terminal shield that faces in the same direction as a handle of a circuit interrupter.
Another aspect of the disclosed and claimed concept is to provide such a safety apparatus in conjunction with a circuit interrupter to provide an improved circuit interrupter apparatus.
Another aspect of the disclosed and claimed concept is to provide such an improved circuit interrupter apparatus that can include the safety apparatus at the load side of the circuit interrupter, at the line side of the circuit interrupter, or at both the load and line sides of the circuit interrupter.
Accordingly, an aspect of the disclosed and claimed concept is to provide an improved safety apparatus usable with a circuit interrupter having a housing and an electrical apparatus, the electrical apparatus having a number of poles situated on the housing, the number of poles having a plurality of terminals, the plurality of terminals being structured to be electrically connected with a number of line and load conductors, each pole of the number of poles being electrically connected with a corresponding pair of terminals of the plurality of terminals and including a set of separable contacts that are movable between a CLOSED state wherein the pair of terminals are electrically connected together an OPEN state wherein the pair of terminals are electrically disconnected from one another. The safety apparatus can be generally stated as including a terminal shield that can be generally stated as including a first wall that is structured to overlie at least a portion of at least a first terminal of the plurality of terminals, an indication circuit situated at least in part on the terminal shield and that can be generally stated as including a number of electrical connectors, at least a first electrical connector of the number of electrical connectors being structured to be electrically connected with the at least first terminal, the indication circuit further can be generally stated as including at least a first indicator that is structured to output at least one of a visual indication and an audible indication when the at least first terminal is electrically energized by the number of line and load conductors.
Another aspect of the disclosed and claimed concept is to provide an improved circuit interrupter apparatus that can be generally stated as including a circuit interrupter and a safety apparatus, the circuit interrupter can be generally stated as including a housing and an electrical apparatus, the electrical apparatus can be generally stated as including a number of poles situated on the housing, the number of poles having a plurality of terminals, the plurality of terminals being structured to be electrically connected with a number of line and load conductors, each pole of the number of poles being electrically connected with a corresponding pair of terminals of the plurality of terminals and including a set of separable contacts that are movable between a CLOSED state wherein the pair of terminals are electrically connected together an OPEN state wherein the pair of terminals are electrically disconnected from one another, the safety apparatus can be generally stated as including a terminal shield and an indication circuit, the terminal shield can be generally stated as including a first wall that overlies at least a portion of at least a first terminal of the plurality of terminals, the indication circuit being situated at least in part on the terminal shield and can be generally stated as including a number of electrical connectors, at least a first electrical connector of the number of electrical connectors being structured to be electrically connected with the at least first terminal, the indication circuit further can be generally stated as including at least a first indicator that is structured to output at least one of a visual indication and an audible indication when the at least first terminal is electrically energized by the number of line and load conductors.
A further understanding of the disclosed and claimed concept can be gained from the following Description when read in conjunction with the accompanying drawings in which:
Similar numerals refer to similar parts throughout the specification.
An improved safety apparatus 4 in accordance with a first embodiment of the disclosed and claimed concept is depicted in
As can be understood from
The poles 18A, 18B, and 18C each include a set of separable contacts that are indicated at the numerals 22A, 22B, and 22C, respectively and which may be collectively or individually referred to herein with the numeral 22. The electrical apparatus 16 further includes an operating mechanism that is not expressly depicted herein that moves the sets of separable contacts 22 between a CLOSED state such as is depicted generally in
The poles 18A, 18B, and 18C each additionally include a corresponding second side conductive element indicated at the numerals 30A, 30B, and 30C that are at a second side of the sets of separable contacts 22 and which may be collectively or individually referred to herein with the numeral 30. Furthermore, the poles 18A, 18B, and 18C each additionally include a corresponding second side terminal indicated at the numerals 34A, 34B, and 34C, and which may be collectively or individually referred to herein with the numeral 34, and which are electrically connected with the corresponding second side conductive element 30 of each pole 18. In the depicted exemplary embodiment, the second side terminals 34 are load side terminals that are electrically connected with a set of load conductors that are indicated at the numerals 38A, 38B, and 38C, which may be collectively or individually referred to herein with the numeral 38.
It thus can be understood that the sets of separable contacts 22, the first side and second side conductive elements 24 and 30 that are situated at first and second sides of the sets of separable contacts 22 and are electrically connected therewith, and that are, in turn, electrically connected with the first and second side terminals 28 and 34, together complete a circuit between the first side terminals 28 and the second side terminals 34 of the poles 18 when the sets of separable contacts 22 are in the CLOSED state such as is depicted generally in
As is best shown in
The safety apparatus 4 can be said to include a terminal shield 46 and an indication circuit 48, with the indication circuit 48 being incorporated into the terminal shield 46. That is, the indication circuit 48 is situated at least in part upon the terminal shield 46, but as will be set forth in greater detail elsewhere herein, certain portions of the indication circuit 48 depend from or extend from the terminal shield 46 for electrical connection with other structures.
The terminal shield 46 can be said to include a top wall 52 and to further include a pair of side walls 54A and 54B that depend from the top wall 52. The terminal shield 46 further includes a pair of divider walls 58A and 58B that are situated between the side walls 54A and 54B. The top wall 52 includes a lip 60 that protrudes beyond the side walls 54A and 54B and beyond the divider walls 58A and 58B and that overlies a portion of the housing 12 when the safety apparatus 4 is mounted to the circuit interrupter 6.
The top wall 52 can be said to include a top surface 64, a portion of which is generally planar and faces generally away from the circuit interrupter apparatus 10 in the same direction as a handle 65 of the electrical apparatus 16 extends away from the housing 12. The side walls 54A and 54B each include a side surface 66A and 66B, respectively, that are each generally planar and are oriented generally parallel with one another and perpendicular with the top surface 64. The divider walls 58A and 58B are oriented generally parallel with the side walls 54A and 54B.
The indication circuit 48 of the safety apparatus 4 includes a set of visual indicators that are indicated at the numerals 72A, 72B, and 72C, which may be collectively or individually referred to herein with the numeral 72. In the depicted exemplary embodiment, the visual indicators are lights, but it is understood that other types of visual indicators such as visible meters, color-changing indicators, and the like without limitation may be employed as the visual indicators. It is also understood that the visual indicators 72 could instead be replaced with audible indicators such as loudspeakers and the like and still be within the scope of the disclosed and claimed concept.
It is noted that the safety apparatus 4 is depicted in
The indication circuit 48 further includes a set of first electrical connectors 76A, 76B, and 76C, which may be collectively or individually referred to herein with the numeral 76, which are electrically connected with the visual indicators 72, and further includes a set of second electrical connectors that are indicated at the numerals 78A, 78B, and 78C, which may be collectively or individually referred to herein with the numeral 78, which are also electrically connected with the visual indicators 72. As can be understood from
As can be understood from
The same can be said of the second side safety apparatus 204 with respect to the second side of the electrical apparatus 16. That is, the second side safety apparatus 204 can likewise be sold with the circuit interrupter 6 or can be provided as a retrofit product that can be retrofitted to an existing circuit interrupter 6. It is reiterated that in either situation, the safety apparatus 4 can be received on the first side, the second side, or on both sides of the circuit interrupter 6 to form the improved circuit interrupter apparatus 10.
As can further be understood from
As can be understood from
As can be seen in
As noted, confusion can sometimes exist in a given circuit interrupter installation because whether one physical side of a circuit interrupter is connected with the line conductors 36 or the load conductors 38 may be unclear. By providing the safety apparatus 4 on both sides of the circuit interrupter 6, the technician can rapidly assess whether either or both sides of the circuit interrupter 6 remain energized. For example, if the technician knows that work is to be performed on a certain side of the circuit interrupter 6 but does not know which side is the line side or the load side, the technician can switch the circuit interrupter 6 from the ON condition to the OFF condition and can then visually assess the visual indicators 72. If the visual indicators 72 at the side of the circuit interrupter 6 where the work needs to be performed remain illuminated in the OFF condition of the circuit interrupter, this will advise the technician that another circuit interrupter upstream of the circuit interrupter 6 will need to be switched to its OFF state in order to remove the electrical energy from that side of the circuit interrupter 6.
Moreover, since the indication circuit 48 includes a visual indicator 72 for each of the poles 18, the technician can identify, for instance, a failure of the circuit interrupter 6. For instance, if the circuit interrupter 6 is in its OFF condition, such as in
An improved safety apparatus 504 in accordance with a second embodiment of the disclosed and claimed concept is depicted generally in
As can be understood from
More specifically, the poles 518A, 518B, and 518C each correspondingly include a first side terminal 528A, 528B, and 528C, which may be collectively or individually referred to herein with the numeral 528, and a second side terminal 534A, 534B, and 534C, which may be collectively or individually referred to herein with the numeral 534. It is also noted that the circuit interrupter apparatus 510 includes two instances of the safety apparatus 504, and these two instances are referred to with the numeral 604, which refers to the safety apparatus 504 at the first side of the circuit interrupter 506, and with the numeral 704, which refers to the safety apparatus 504 that is situated at the second side of the circuit interrupter 506. As before, the first and second side safety apparatuses 604 and 704 are identical to one another, and the reversed numerology in
As can be understood from
It thus can be understood that any of the visual indicators 572 will be illuminated when either of the poles 518 between which the visual indicator 572 is electrically connected is energized. As such, the visual indicator 572A will be illuminated whenever either of the poles 518A and 518C is electrically energized at its terminals 528 and 534, respectively. Likewise, the visual indicator 572B will be illuminated whenever either of the poles 518A and 518B is electrically energized at the corresponding terminals 528 and 534. Likewise, the visual indicator 572C will be illuminated whenever of the poles 518B and 518C is electrically energized at the corresponding terminals 528 and 534. Such electrical illumination of the visual indicators 572 advantageously occurs without a need of providing an additional connection with a neutral conductor in order to complete an electrical circuit and is due to the three electrical phases to which the poles 518 are connected are out of phase with one another in an understood fashion. An electrical power system that does not have a neutral conductor is typical when a transformer is connected in a delta configuration. It can be seen that in the event that the circuit interrupter 6 has only a single pole, the safety apparatus 4 with its wiring between the pole and the neutral conductor will need to be provided inasmuch as a plurality of poles would not be provided in a single pole application.
It thus can be seen that the safety apparatuses 4 and 504 and the circuit interrupter apparatuses 10 and 510 advantageously provide a rapid indication to a technician whether any portions of a circuit interrupter 6 and 506 remain energized, and indicate specifically which portions of the circuit interrupters 6 and 506 remain energized. This enables a technician to rapidly assess whether or not certain operations can be performed on the circuit interrupters 6 and 506 or whether additional steps need to be taken in order to make the circuit interrupters 6 and 506 safe for operations being performed thereon. This advantageously saves time and effort and is a safety improvement. Other advantages will be apparent.
While specific embodiments of the disclosed concept have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangements disclosed are meant to be illustrative only and not limiting as to the scope of the disclosed concept which is to be given the full breadth of the claims appended and any and all equivalents thereof.
