ERGONOMICALLY ENHANCED INTERFACE FOR MEDIUM-VOLTAGE CIRCUIT BREAKER

TESTING

Technical field of the invention

The present invention relates to medium voltage circuit breaker testing systems. In particular, the present invention relates to an apparatus as an ergonomically enhanced interface to be used in such tests.

Background of the Invention

Medium-voltage circuit breakers are subjected to routine on-line tests under periodical maintenance measures. The procedure of medium-voltage circuit breaker testing includes well-known measurements for test values including "opening-time measurement", "closing-time measurement" and "contact resistance measurement" (or contact transition resistance measurement) of circuit breaker (hereinafter abbreviated as "breaker"). To this end, the breaker is to be properly brought in electrical communication with a respective medium-voltage cubicle (a.k.a. mid-voltage cubicle, or medium-voltage switch gear cubicle, hereinafter abbreviated as "cubicle"). For each of the measurements, several electrical communication line ends of the breaker are to be removably brought into contact with respective electrical communication line ends of the cubicle. Said line ends commonly include those designated to "auxiliary supply", "breaker trip", "breaker is on", "neutral", and in the case where the breaker is vacuum- type instead of contactor-type, "motor charging (breaker motor supply, or circuit breaker spring charging motor supply)". In the present specification, the breaker is assumed to be of "vacuum-type", but the teaching can be adapted to other types of mid-voltage circuit breakers, mutatis mutandis.

Usually, a breaker has a matrix of multiple line ends such as male pins or female pin plugs arranged in the form of a pin plug socket connector; usually male pins. Correct breaker line ends to be used in performing each of the above-mentioned measurements are to be first checked from connection diagrams obtained from a respective breaker manufacturer. Said line ends of the breaker should be then connected to respective line ends of the cubicle. This is a highly demanding procedure, and errors in selecting correct line ends may cause serious damage.

For engaging each of the respective line ends of the breaker and the cubicle, the connections are established using e.g. alligator clips and banana connectors, sizes of which are known to be much greater than said multiple line ends in the form of pins. In the case where adjacent pins are not sufficiently distant from to each other, a clip may contact to a non-designated pin, which would result in damages related to formation of a short circuit. In addition, the clips used in connections are geometrically different from pins, which results in unstable connections, i.e. the clips can release respective designated pins before the measurement is finished. Considering that some of said connections also include formation of bridges between each other, a multiplicity of cables with such connectors are generally to be employed. As a result, each single measurement requires a high-complexity work which take much longer time when compared to the test procedure itself. Arranging connections between line ends correctly for successful testing thus requires a tremendous extent of accuracy in labor, which takes a high amount of time and labor force.

For performing all of said opening-time, closing-time and contact resistance (or contact transition resistance) measurements in one go, all of the connections for performing each of the measurements must be established before starting the test procedure. Accordingly, the problems defined above accumulate with each other. In the case where the line ends of the cutter are provided in the form of a matrix as those arranged in the form of a male pin plug socket connector, the level of difficulty gets higher than triplicate because of insufficiency of space in the matrix. Referring to Fig.1(a) to Fig.1(e), a commonly used first way of breaker testing is performed when the breaker (50) is connected to a respective cubicle (on-line testing). Here, the breaker (50) is kept adjacent to (or in vicinity of) the cubicle (not shown). Such test can be usually performed using a testing device (40) to be brought into electrical communication with respective line ends of the breaker (50). A testing device (40) can be commercially obtained (such as that under brand name "CIBANO 500" supplied by Omicron, available in the market as of 2020).

In the first way, the above-mentioned line ends of the cubicle and respective line ends of a testing device (40), are to be connected to each other, over suitable terminals on the cubicle upon selection from the project drawings. In the case of mistake in selection, the system can go offline which is undesirable. Upon connecting the correct line ends, the breaker (50) is brought out from its respective cubicle, and to this end, its plug (usually a male connector plug which includes a matrix of multiple pins) is to be disconnected from the cubicle. The breaker (50) is then turned around to expose the "primary disconnects" (80) (a.k.a. primary contacts) of the breaker (50); for enabling establishment of well-known necessary electrical connections thereover to the testing device (40), and necessary bridgings. Then, the plug of the breaker (50) should be re-connected to the cubicle; but the cable organizer of the plug is usually short and it is highly difficult to establish engagement between the plug and the cubicle. Thus, said first way is ergonomically disadvantageous and requires high extent of labor and attention.

Fig.1(a) to Fig.1(e) show schematics visualising exemplary connections related to opening/closing time in the first way of testing. For breaker type, suitable line ends of the breaker (50) to be connected with respective terminals on the cubicle, are to be selected by looking up from the project drawings; said line ends and (+) and (-) ends of respective terminals being designated for test objects including "closing coil" (MC), "opening coil" (M01), "closing release coil" (RL1) and if the breaker is of vacuum type, "motor charging" (M). Each of the terminals include at least two cables at both sides thereof, which can be considered as for establishing internal cabling for terminal input/output. Hence, the internal cabling connections to closing coil, opening coil, motor charging and closing release coil from said terminals, are to be determined. To this end, cables for respective terminals are unplugged one by one; and one by one measurements should be performed to confirm whether the respective cables are in fact designated to closing coil, opening coil, motor charging and closing release coil. In the respective terminals, all of the cables other than those which are designated as explained above, are to be unplugged/disconnected from the cubicle. One by one measurements are to be performed to confirm that said disconnected cables are no more energized; and referring to the project, the non-disconnected cables are to be safely de energized. Then, input connections (referred to as Bl, B2, B3, B4 and BN) from the breaker (50) are to be made to respective terminals, cables of which being already disconnected as mentioned above. For instance, an exemplary connection from breaker (50) line ends referred to as Bl and BN are established to the respective cubicle terminals referred to XX/253 and XX/232 (see: Fig.1(b)). The shortcomings and difficulties related to the establishment of such connections are already mentioned above. On the other hand, some of the connections of the line ends can be maintained without change, which are exemplified with references Al, A2, A3 and AN.

A commonly used second way of breaker (50) testing is performed when the breaker (50) is remote/disconnected from the respective cubicle. In the second way, the breaker (50) is moved rather away from the cubicle and thereby tested "remotely". Throughout the present specification, the terms "remote" and "remotely" correspond to that the breaker (50) is disconnected from a respective cubicle, thus the test can be considered to be performed "off-line".

The second way does not necessitate a re-plugging the plug connector of the breaker (50) directly to the cubicle. Fig.2(a) to Fig.2(e) show schematics visualizing exemplary connections related to opening/closing time in the second way of testing. In accordance with breaker (50) type, suitable line ends of the breaker (50) to be connected with respective terminals on the cubicle, are to be selected by looking up from the project drawings; said line ends and (+) and (-) ends of respective terminals being designated for test objects including "closing coil", "opening coil", "motor charging" and "closing release coil". Line ends referred to as Al, A2, A3 and AN from the testing device (40) are to be connected to respective line ends of the breaker (50). Line ends referred to as Bl, B2, B3, B4 and BN of the testing device (40) are connected to respective line ends of the breaker (50) (said line ends usually being in the form of pins on the plug connector thereof), which are respectively designated to closing coil, opening coil, motor charging and closing release coil. Looking-up from the project drawings of the breaker (50) manufacturer, it can be discovered that the (+) and (-) line ends of the closing coil respectively correspond to e.g. 4 ^th and 14 ^th pins of the breaker (50) plug, and Bl and BN line ends of the testing devices (40) can be connected to said respective pins. Connections around the "primary disconnects" of the breaker (50) are also be established as in the first way explained above. Establishment of said connections also inherit several shortcomings and difficulties: considering the space limitations between the multiplicity of pins as line ends on the breaker (50) plug, crocodile connectors are to be one by one electro-mechanically engaged to designated pins of the breaker (50) plug without mistake, which slows down the procedure and requires a high level of attention. Mechanical instability in engagement between the crocodile connectors and substantially cylindrical pins is inevitable. The size difference between common crocodile connectors and pins also potentially causes an undesired connection (short circuit) between adjacent pins, which results in damage. Taking the necessary bridge connections between different crocodile connectors using banana connectors, the cabling is complicated and it is difficult to work between crowded and tangled cabling without errors is highly difficult and ergonomically disadvantageous. Fig.1(e) and Fig.2(e) schematically show exemplary connections between line ends on a testing device (40) and a breaker (50), applicable to prior art methods named above as "first way" and "second way", respectively.

Referring to both of the first way and second way of testing discussed above, the same measures and conditions are also valid for "contactor type" breakers, other than that the contactor type breakers do not include "motor charging" means, and B4-BN outputs connected thereto are to be disabled over testing device (40) software throughout the testing procedure.

Summary of the Invention

The present invention proposes an interface to be used in medium voltage circuit breaker testing, arranged to provide electrical communication between such breaker and a respective testing device; comprising the following: a first "closing coil" connection port, a first "opening coil" connection port, and a first "closing release coil" connection port each for receiving means for electrical communication with respective "closing coil" line end, "opening coil" line end and "closing release coil" line end on the breaker; and a second "closing coil" connection port in electrical communication with the first "closing coil" connection port, a second "opening coil" connection port in electrical communication with the first "opening coil" connection port, and a second "closing release coil" connection port in electrical communication with the first "closing release coil" connection port; each for being brought into electrical communication with respective "closing coil" line end, "opening coil" line end and "closing release coil" line end of a testing device. Objects of the Invention

The primary object of the present invention is to overcome the drawbacks outlined above.

Another object of the present invention is to propose an interface for facilitating the testing of medium voltage circuit breakers.

Another object of the present invention is to propose an interface for enhancing the labor safety in testing of medium voltage circuit breakers.

A further object of the present invention is to propose a simple, reliable and low-cost interface for shortening the duration and minimizing the labor costs and potential damages related to medium voltage circuit breakers testing.

Other objects of the present invention will become apparent from accompanied drawings, brief descriptions of which follow in the next section as well as appended claims.

Brief Descriptions of the Drawings The appended drawings, brief description of which are provided below, are given solely for the purpose of exemplifying embodiments according to the present invention.

Fig.l shows a schematic view of an exemplary connections around (a) closing release coil, (b) closing coil, (c) closing coil, and (d) motor charging, established in the first way of breaker testing. Fig.1(e) shows schematic view of connections between the testing device and primary connects on the breaker at such first way of testing.

Fig.2 shows a schematic view of an exemplary connections around (a) closing release coil, (b) closing coil, (c) closing coil, and (d) motor charging, established in the second way of breaker testing. Fig.2(e) shows schematic view of connections between the testing device and primary connects on the breaker at such second way of testing.

Fig.3 (a) schematically shows connections between an interface according to the present invention, a testing device, and a breaker. Fig.3(b) shows an exemplary, preferred embodiment of the interface according to the present invention. Optional features are shown using reference numerals in parantheses.

Detailed Description of the Invention Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention relates to a way of breaker testing, which includes testing a breaker when the same is remote from a respective cubicle. Accordingly, the present invention proposes an ergonomically enhanced apparatus in the form of an interface (100) to be used in medium voltage circuit breaker (50) testing. The interface (100) is to be considered as a physical entity, which may be e.g. in the form of a panel. The interface (100) is arranged to provide electrical communication between a breaker (50) and a respective testing device (40). The interface (100) according to the present invention enables a new way of breaker (50) testing over itself, and said new way includes testing the breaker (50) when the same is remote from a respective cubicle. To realize the testing, the interface (100) is to be employed between a breaker (50) (i.e. medium-voltage circuit breaker) and a testing device (40).

The interface (100) according to the present invention comprises the following: a first "closing coil" connection port (1) (or a set thereof), a first "opening coil" connection port (2) (or a set thereof), and a first "closing release coil" connection port (3) (or a set thereof) each for receiving means for electrical communication with respective "closing coil" line end (51) (or a set thereof), "opening coil" line end (52) (or a set thereof) and "closing release coil" line end

(53) (or a set thereof) of a breaker (50) (i.e. medium voltage circuit breaker (50)); and a second "closing coil" connection port (11) (or a set thereof) in electrical communication with the first "closing coil" connection port (1) (or said set thereof), a second "opening coil" connection port (12) (or a set thereof) in electrical communication with the first "opening coil" connection port (2) (or said set thereof), and a second "closing release coil" connection port (13) (or a set thereof) in electrical communication with the first "closing release coil" connection port (3) (or said set thereof); each for being brought into electrical communication with respective "closing coil" line end (41), "opening coil" line end (42) and "closing release coil" line end (43) of a testing device (40) (i.e. medium voltage circuit breaker testing device).

For being also suitable for testing of a vacuum type circuit breaker (50), the interface (100) can further include: a first "motor charging" connection port (5) (or a set thereof) for receiving means for electrical communication with a respective "motor charging" line end (55) on such breaker (50), and a second "motor charging" connection port (15) (or a set thereof) in electrical communication with the first "motor charging" connection port (5) (or said set thereof), for receiving means for electrical communication with a respective "motor charging" line end (45) on such testing device (40).

Within the context of the present application, each "set" of connection ports corresponds to respective (+) and (-) line ends to enabling the performance of a respective step of the breaker test procedure. For instance, a set of first "closing coil" connection port (1) refers to (+) and (-) line ends for being electrically matched with a set of "closing coil" line ends (51) of a respective breaker (50). Similarly, a set of second "closing coil" connection port (11) refers to (+) and (-) line ends for being electrically matched with a "closing coil" line end (41) of a testing device (40). The same applies to the first and second sets of "opening coil" connection ports (2 and 12), "closing release coil" connection ports (3 and 13), and "motor charging" connection ports (5 and 15).

The interface (100) according to the present invention eliminates the complexity at preparing and ending the testing procedure, and provides a simple interface (100) on which the connection ports can be labelled. Thus, the required preparation and finishing times, and the probability of labor errors and damages is lowered.

In a possible embodiment, the first "closing coil" connection port (1), the first "opening coil" connection port (2), the first "closing release coil" connection port (3) and where applicable, the first "motor charging" connection port (5) can be arranged to have a distance with each other, said distance being 1 cm or higher, preferably 2 cm or higher. This embodiment enhances the spaciousness between said ports, thereby further facilitates the establishment of connections of the interface (100) with the breaker (50). Thus, the preparation and finishing times, and the probability of labor errors and damages are further lowered.

The first "closing coil" connection port (1), the first "opening coil" connection port (2), the first "closing release coil" connection port (3) and where applicable, the first "motor charging" connection port (5) can be disposed as a matrix of line ends on a pin plug socket connector. Said pin plug socket connector can be female for being engaged with a respective pin plug socket connector which can include respective "closing coil" line end (51), "opening coil" line end (52) and "closing release coil" line end (53) and where applicable, "motor charging" line end (55) of a breaker (50). This embodiment provides the chance of preparation of the interface (100) beforehand in accordance with a designated breaker (50) model, such that the first "closing coil" connection port (1), the first "opening coil" connection port (2), the first closing release coil" connection port and where applicable, the first "motor charging" connection port can be arranged in accordance with the arrangement of respective line ends on a pin plug socket connector of a certain type of breaker (50). All of the first "closing coil" connection port (1), the first "opening coil" connection port (2), the first "closing release coil" connection port (3) and where applicable, the first "motor charging" connection port can be thus instantly connected and deliberately disconnected with respective line ends of such breaker (50) at once, without leaving any possibility to labor errors. Geometric incompatibilities between connectors (e.g. crocodile connectors) and the respective line ends of the breaker (50) pin plug socket connector, and all of the problems (e.g. occurrence of undesired short circuits) related to smallness of distances between adjacent pins on such pin plug socket connector are thus eliminated. Hence, this embodiment provides labor safety, labor time economy, along with full elimination of potential damages.

Any of the above mentioned embodiments can further include a first visual indicator (71), a second visual indicator (72), a third visual indicator (73) and where applicable a fourth visual indicator (74), which are respectively arranged to indicate working status of first "closing coil" connection port (1), the first "opening coil" connection port (2), the first "closing release coil" connection port (3) and where applicable, the first "motor charging" connection port (5). This facilitates the visual tracking of the testing process, along with visual tracking of "health status" of the interface (100). For instance, in the case where a connection between one of said first connection ports and a respective second connection port is lost, this can be easily detected whilst testing of a breaker (50) without confusion. One or more of the visual indicators (71-74) can be in the form of lamps, for instance LEDs.

The interface (100) can be preferably arranged on a panel board, thereby providing an enhanced stability when in use.

Such interface (100), in particular which is provided with said visual indicators (71-74), can be preferably arranged such that the panel board substantially defines a surface parallel to the gravity vector when in use; thereby facilitating visual tracking of the working status and health status of the interface (100) in operation.

In a further preferred embodiment, the interface (100) can be provided with a plurality of wheels (not shown), thereby facilitating its transfer for successively testing of multiple breakers (50).

EXAMPLE:

Fig.3(a) and Fig.3(b) show schematics for visualizing exemplary connections related to opening/closing time in the new way of testing. Fig.3(a) schematically shows exemplary connections between line ends on a testing device (40) and a breaker (50), over the interface (100). Fig.3(b) shows an exemplary, preferred embodiment of the interface (100) according to the present invention, which includes a first part (101) arranged to match with a pin plug socket connector of a breaker (50), and a second part (102) arranged to be matched with respective line ends of a testing device (40). In Fig.3(b), only exemplary electrical connections between a set of first "closing coil" connection ports (1) on a first part (101) and a set of second "closing coil" connection ports (11) on a second part (102) are shown, for reducing the complexity level of the drawing. In Fig.3(b), the interface (100) is shown to be provided on a panel board as preferred, and further preferably includes a plurality of visual indicators (71-74) as discussed above. Preferred existence of wheels are not shown, yet the enablement thereof is evident to a skilled person. Here, the first part (101) includes the first "closing coil" connection port (1), a first set of "opening coil" connection ports (2), and a first set of "closing release coil" connection ports (3) each for being brought into electrical communication with respective sets of "closing coil" line ends (51), "opening coil" line ends (52) and "closing release coil" line ends (53) on a breaker (50). Here, the interface (100) is adapted to be also used with vacuum contact breakers, therefore it is shown to include a first set of "motor charging" connection ports (5) for being brought into electrical communication with respective set of "motor charging" line ends (55) of such breaker (50); and a second set of "motor charging" connection ports (15) for being brought into electrical communication with a "motor charging" line end (45) of a testing device (40).

Firstly, breaker-side line ends related to breaker test (i.e. "closing coil" line end (51), "opening coil" line end (52) and "closing release coil" line end (53) of a certain, respective breaker (50)) are determined in accordance with the project drawings/schematics provided by respective breaker (50) manufacturer. The "closing coil" line end (51), "opening coil" line end (52) and "closing release coil" line end (53) can correspond to respective (+) and (-) ends (and "motor charging" line end (55) in the case where the breaker (50) is e.g. vacuum type instead of contactor type). Said breaker-side line ends can be already provided in the form of a matrix of male pins on a pin plug socket connector, along with a plurality of other pins which are irrelevant to the test; and corresponding line ends (1, 2, 3 and optionally 5) on the interface (100) can be arranged accordingly, as basically schematized in Fig.3(b).

Referring to Fig.3(a) and Fig.3(b), for instance (+) and (-) ends of "closing coil" can be connected to related line ends of the breaker (50) (which can be determined as e.g. 4 ^th and 14 ^th pins of a matrix of pins on a pin plug socket connector of a certain model breaker, upon looking-up from project drawings supplied by its manufacturer); and related connections of a set of respective first "closing coil" connection ports (1) provided on the interface (100) is established accordingly. The same is performed with regard to sets (i.e. (+) and (-) ends) of first "opening coil" connection ports (2), first "closing release coil" connection ports (3) and where applicable, first "motor charging" connection ports (5) (none of said ports nor connections are shown in Fig.3(b)).

"Closing coil" line end (41), "opening coil" line end (42) and "closing release coil" line end (43), and where applicable, "motor charging" line end (45) of the testing device (40) (which respectively correspond to those indicated as Bl, B2, B3 and B4 in Fig.3(a), as well as in Fig.1(e) and Fig.2(e)) are brought into electrical communication with (+) line ends of the second "closing coil" connection port (11), the second "opening coil" connection port (12), the second "closing release coil" connection port (13) and where applicable, the second "motor charging" connection port (15) of the interface (100). A further line end (an "earth current transformer" line end indicated as BN) of the testing device (40) can be brought into electrical communication with (-) line ends of said second "closing coil" connection port (11), second "opening coil" connection port (12), second "closing release coil" connection port (13) and where applicable, second "motor charging" connection port (15) of the interface (100).

The interface (100) can further include a parallel circuit directed to one or more visual indicators (71-74) in electrical communication with said line ends of second "closing coil" connection port (11), second "opening coil" connection port (12), second "closing release coil" connection port (13) and where applicable, second "motor charging" connection port (15); arranged for energizing respective visual indicators when a command (related to respective steps of the test procedure) is directed to any of said line ends by the testing device (40).

Respective electrical communications between the first "closing coil" connection port (1), the first "opening coil" connection port (2), the first "closing release coil" connection port (3) and where applicable, the first "motor charging" connection port (5) can be provided on a matrix of line ends, in the form of a pin plug socket connector as described above (e.g. female, arranged on a first part (101)), arranged to match with a respective pin plug socket connector (e.g. male) of the breaker (50) to be subjected to tests. Accordingly, as depicted in Fig.3(b), the interface (100) can include a first part (101) arranged to match with a pin plug socket connector of a breaker (50). Thus, said establishment can be easily and instantly performed by engaging the first part (101) with a respective pin plug socket connector of the breaker (50) to be subjected to tests. Since the matrix designs and line end distribution in pin plug socket connectors of various breaker models can vary, pin connections on a first part (101) can be adapted/revised in accordance with different breaker models. Upon learning the gist of the present innovation and looking-up from project drawings of a target breaker, such adaptation/revision is very easy for a person skilled in the field of electrical engineering.

Before starting the testing procedure, necessary connections are to be made between several line ends on the test device (40) and respective "primary disconnects" on the breaker (50). In Fig.3(a), such line ends and respective primary disconnects are referred to as Al, A2, A3 and AN. Said connections are known from the prior art "first way" and "second way" of testing which are respectively schematized in Fig.1(e) and Fig.2(e).

In the case where the interface (100) includes a first "motor charging" connection port (5) and a second "motor charging" connection port (15) as mentioned above, and if the breaker (50) to be tested is of contactor type (i.e. which does not include "motor charging" function), electrical communication between "earth current transformer" line end (which can be indicated as BN) and "closing coil" line end (41) (which can be indicated as Bl) on the testing device (40) can be disabled, e.g. over a test software provided by a respective testing device manufacturer. Reference signs:

1 first "closing coil" connection port

2 first "opening coil" connection port 3 first "closing release coil" connection port

5 first "motor charging" connection port

11 second "closing coil" connection port

12 second "opening coil" connection port

13 second "closing release coil" connection port 15 second "motor charging" connection port

40 testing device

41 "closing coil" line end of the testing device

42 "opening coil" line end of the testing device

43 "closing release coil" line end of the testing device 45 "motor charging" line end of the testing device

50 breaker

51 "closing coil" line end of the breaker

52 "opening coil" line end of the breaker

53 "closing release coil" line end of the breaker 55 "motor charging" line end of the breaker

71 first visual indicator

72 second visual indicator

73 third visual indicator

74 fourth visual indicator 80 primary disconnect

100 interface

A1 an input/output on a test device

A2 an input/output on a test device A3 an input/output on the test device AN an input/output on the test device B1 an input/output on the test device B2 an input/output on the test device B3 an input/output on the test device B4 an input/output on the test device BN an input/output on the test device

RL1 closing release coil

XB/10 a closing release coil related first (positive) line end on a breaker, in a set of "closing release coil" line ends

XX/ 252 (+) a closing release coil related first (positive) line end of a cubicle

XB/20 a closing release coil related second (negative) line end on a breaker, in a set of "closing release coil" line ends XX/231 (-) a closing release coil related second (negative) line end of a cubicle MC closing coil

XB/4 a closing coil related first (positive) line end on a breaker, in a set of "closing coil" line ends XX/253 (+) a closing coil related first (positive) line end of a cubicle

XB/14 a closing coil related second (negative) line end on a breaker, in a set of "closing coil" line ends

XX/232 (-) a closing coil related second (negative) line end of a cubicle M01 opening coil

XB/31 an opening coil related first (positive) line end on a breaker, in a set of "opening coil" line ends

XX/271 (+) an opening coil related first (positive) line end of a cubicle

XB/30 an opening coil related second (negative) line end on a breaker, in a set of "opening coil" line ends

XX/236 (-) an opening coil related second (negative) line end of a cubicle

M motor charging

XB/25 a motor charging related first (positive) line end on a breaker, in a set of "motor charging" line ends

XX/201 (+) a motor charging related first (positive) line end of a cubicle

XB/35 a motor charging related second (negative) line end on a breaker, in a set of "motor charging" line ends

XX/202 (-) a motor charging related second (negative) line end of a cubicle