Patent ID: 12261419

Identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. However, elements disclosed in one embodiment may be beneficially utilized on other embodiments without specific recitation.

DETAILED DESCRIPTION

The present disclosure provides a plug-on neutral (PON) device and kit for a switchboard or panelboard, including the I-Line™ series of switchboards or panelboards from Schneider Electric USA, Inc. that enables flexible and modular assembly and installation of the PON device with the switchboard or panelboard. The PON device can be assembled and/or installed using a single kit.

The PON device is configured to be installed on a bus assembly (also referred to as a stack) of the switchboard or panelboard, and in particular to a neutral bus of the bus assembly when the neutral bus is disposed next to the phase buses of the bus assembly. The PON device and kit are designed to reduce or minimize the amount of time and skill needed to perform this installation using ordinary mechanical assembly skills, without the need for particular electrical technician skills. The PON device is configured to be slid into position and secured to the bus assembly for electrically connecting to the neutral bus a source neutral input that is associated with source phase input of one or more grouped branch breakers that are grouped with the PON device. The PON device can be disposed adjacent or proximate the grouped branch breaker. With the board (meaning a switchboard or panelboard) configured to have the neutral bus located in a front area of the switchboard, next to the phase buses, associated source phase and neutral inputs are received by the PON device and adjacent branch breakers at the front of the board. This eliminates the need to provide source neutral inputs to the back of the board, which reduces the amount of cable that enters the board and minimizes electrical joints needed by the board.

In addition, multiple neutral circuits can be connected to one PON device100when ground fault monitoring by the PON device is not required. The limiting factors that limits the number of neutral circuits that can be connected to a single PON device100is the number of cable connections available on the PON device100and a requirement to not exceed an ampacity rating of the PON device100. By servicing multiple neutral circuits, space occupied by the PON device100reduced or minimized.

With reference toFIGS.1and2, shows respective perspective side and top views of an example PON device100disposed in an interior area of a switchboard10, installed on a bus assembly12and breaker support frame14disposed within switchboard10. Switchboard10shown inFIGS.1and2is shown as an example. The disclosure applies as well to a panelboard. All references and illustrations of a switchboard are equally relevant to a panelboard. Bus assembly12includes parallel phase and neutral buses, which in the example shown include phase buses30A-30C (referred to collectively as phase buses30) and neutral bus32. Bus assembly12, PON device100, and branch breakers202are configured for plug-on connections in which PON device100and branch breakers202plug-on to neutral bus32and phase buses30, respectively for a secure, electrical connection, such as provided by the I-Line™ series of switchboards or panelboards from Schneider Electric USA, Inc. Phase buses30, neutral bus32, and breaker support frame14can all be parallel to one another and oriented vertically or horizontally and disposed interior to switchboard10at a front section of switchboard10. A nonconductive material34is disposed in between each of the phase buses30as well as between phase bus30C and neutral bus32for providing electrical insulation.

With reference toFIGS.1-3, PON device100has a housing102that includes a first side housing102A and a second side housing102B.FIG.3shows a side view of an example PON device100with second side housing102B shown as transparent or removed. Housing102has a source end101and a bus end103. Source end101is provided with a lugs assembly114having lug apertures116, each lug aperture116configured to receive an external neutral source input conductor310that electrically connects to a terminal lug308. Terminal lugs308can be secured interior to housing102, e.g., by bolt304and nut306, although the disclosure is not limited to a particular structure for securing terminal lugs308in PON device100. Neutral source input conductor310can be received within lug apertures116and secured to one or more terminal lugs308, e.g., with a wire binding screw (e.g., see602inFIG.6within aperture116). Each terminal lug304is electrically conductive and configured to receive current from the source neutral input conductor310, such as from a load connected to switchboard10or a line source providing electrical power to switchboard10.

Bus end103of housing102is provided with a phase cooperation portion120and a neutral cooperation portion122. Phase cooperation portion120is configured to physically cooperate with phase buses30A-30C and to physically stabilize PON device100when installed on the bus assembly12. Phase cooperation portion120can have respective mouths, each mouth configured to receive one of the phase buses30. Neutral cooperation portion122is configured to physically cooperate with neutral bus32and to physically stabilize PON device100when installed on the bus assembly12. Neutral cooperation portion122can have a mouth configured to receive the neutral bus32.

In addition, neutral cooperation portion122is provided with an electrical connector108which is electrically conductive and configured to electrically connect to neutral bus32. In addition, electrical connector108electrically connects to a current path302, wherein current path302is electrically connected between electrical connector108and terminal lugs308.

Current path302is an electrically conductive connector. Current path302can be elongated, having a first end312A that electrically connects to terminal lugs308and a second end312B that is configured to physically cooperate with and electrically connect to internal end106B of electrical connector108.

Electrical connector108has an external end106A and an internal end106B, the external end being configured to electrically connect to the neutral bus, the internal end being configured to electrically connect to current path302.

In the example shown, external end106A includes a spring jaw connector that provides a plug-on electrical connection to neutral bus32when neutral bus32is forced into a gap between jaws of the spring jaws. External end106A of electrical connector108is not limited to being configured as a spring jaw connector, and can have other types of configurations that can plug-on and establish an electrical connection, such as a bolted connection.

Furthermore, in the example shown, internal end106B includes a second spring jaw connector that provides a plug-on electrical connection to current path302when force is applied to force second end312B of current path302into a gap between jaws of the second spring jaws. Second end312B can be configured with a circular profile, such as a circular bulb that fits into the gap between jaws of internal end106B, which enables internal end106B to swivel to compensate for any misalignment. Internal end106B of electrical connector108is not limited to being configured as a spring jaw connector, and can have other types of configurations that can plug-on and establish an electrical connection, such as a bolted connection.

PON device100further includes a mounting apparatus110that is configured to secure PON device100in position for maintaining the electrical connection to neutral bus32. In the example shown, mounting apparatus110secures PON device100to breaker support frame14. Mounting apparatus110can be configured with holes for receiving assembly hardware112(e.g., screws, washers, nuts, bolts, etc., which can be provided with a kit.

The kit can include the PON device100, hardware112(e.g., correct number, diameter, length, thread pitch and gauge of hardware112), and access to installation instructions (e.g., a list of contents of the kit, installation instructions, and/or augmented reality to show an assembler, in an approved and certified sequence, where each component of the PON device is to be installed). With reference toFIG.2, PON device100and a group of adjacent branch breakers202A-202D (referred to collectively as branch breakers202) installed on bus assembly12is shown. PON device100and one or two of the adjacent branch breakers202can be in physical contact along at least a portion of their inner surfaces or along their entire inner surfaces. A width WPON of PON device100is smaller than a width of WBB of branch breakers202. In one or more embodiments, PON device100is a low-ampacity device (as shown inFIGS.4and5), wherein WPON is substantially the same as a width WP that corresponds to a width of a portion of one of branch breakers202that is used to receive one phase source input conductor. In this embodiment, a ratio of WPON to WBB can be substantially 1:3. In one or more embodiments, PON device100is a high-ampacity device (as shown inFIGS.6and7), wherein WPON is substantially the same as a 2(WP), meaning a width of a portion of one of branch breakers202that is used to receive two phase source input conductors. In this embodiment, a ratio of WPON to WBB can be substantially 2:3.

In the embodiment shown inFIG.2, PON device100can service the neutral source input conductors (e.g., neutral input conductors310shown inFIG.3) that correspond to the phase source input conductors serviced by all of branch breakers202A-202D. Here, the width of branch breakers202A-202D is 12(WP) and the width PON device100is 2(WP), wherein PON device100occupies only ⅙ the space along bus assembly12that is occupied by the group of branch breakers202for which it services neutral input conductors310. Since PON device100is located near the front of switchboard10, it is easily accessible for installation and maintenance, and the need to feed neutral input conductors310to a rear portion of switchboard10is eliminated. This minimal increase of space occupied by PON device100provides for a large reduction of cabling and reduces an amount and complexity of electrical joints.

With reference toFIGS.4and5, an embodiment of an example low-ampacity PON device100A is shown.FIG.4shows a perspective, opposing-side view of PON device100A andFIG.5shows a perspective, opposing-side view with portions of first housing side102A shown as transparent or removed. PON device100A has up to a first quantity of lug apertures116in lugs assembly114for receiving inputs from the first quantity of neutral source input conductors310(shown inFIG.3), wherein each neutral source input conductor310corresponds to one set of phase source input conductors (not shown), wherein each set of phase source input conductors is connected to one branch breaker202(shown inFIG.2) being serviced by PON device100A in a one-to-one correspondence. PON device100A, when configured based on the low-ampacity embodiment, has ampacity that is limited to below a first threshold, such as 570 amps. PON device100A can thus service a group of branch breakers202that includes up to the first quantity of branch breakers202. In accordance with good practice and/or compliance with regulations, current monitoring is not required.

In the examples shown, the low-ampacity PON device100A can receive inputs from six (limited only by the number of connections for receiving inputs and ampacity of PON device100A) neutral source input conductors310that receive phase currents from phase source input conductors that, in combination, do not exceed the first threshold. In this example, PON device100A has a width W1. In other words, the low-ampacity PON devices100A can service a group of six branch breakers202that in combination have an ampacity that does not exceed the first threshold. In other embodiments, low-ampacity PON device100A can service a group of any number of branch breakers202, wherein the ampacity of the group of branch breakers202does not exceed the first threshold.

With reference toFIGS.6and7, an embodiment of an example high-ampacity PON device100B is shown.FIG.6shows a perspective, opposing-side view of PON device100B andFIG.7shows a perspective, side view with portions of second housing side102B shown as transparent or removed. PON device100B has up to a second quantity of lug apertures116in lugs assembly114for receiving inputs from up to the second quantity of neutral source input conductors310(shown inFIG.3), wherein each neutral source input conductors310corresponds to one set of phase source input conductors, wherein each set of phase source input conductors is connected to one branch breaker202one-to-one correspondence. PON device100B, when configured based on the high-ampacity embodiment, has ampacity that is limited to below a second threshold, such as 1200 amps. In accordance with good practice and/or compliance with regulations, current monitoring is required, and it is required to provide a signal when a current threshold is exceeded to provide for the ability to trip the circuit, e.g., by opening the circuit to prevent current flow. Accordingly, as shown inFIG.7, a current transformer (CT)702is provided for monitoring current through current path302and outputting an output signal that indicates the measured current or when the measured current has exceeded a predetermined threshold. CT702can be placed around current path302. In the example shown, without limitation to a particular configuration, CT702is shaped as a toroid that surrounds current path302. The output signal can be output, for example, to a plug704via one or more wires706that connect CT702to plug704.

Plug704or wire706can be directly connected to an adjacent or nearby branch breaker, such as branch breakers202shown inFIG.2. Wire706can be routed under a cover of branch breaker202and be directly connected to a trip unit of the branch breaker202. In one or more embodiments, branch breaker202can include a mating plug electrically coupled to (e.g., wired to) a ground fault detection circuit in branch breaker202. Plug704can be connected to the mating plug of branch breaker202(or another mating plug external to PON100) to provide the output signal from CT702to the ground fault detection circuit of branch breaker202.

In the examples shown, the high-ampacity PON device100B can receive inputs from up to four (limited only by the number of connections for receiving inputs and ampacity of PON device100B) neutral source input conductors310that receive phase currents from phase source input conductors that, in combination, do not exceed the second threshold. In this example, PON device100B has a width W2, wherein W2is substantially twice as long as W1. In other words, the high-ampacity PON devoice100B can service a group of four branch breakers202(as shown inFIG.2) that in combination have an ampacity that does not exceed the second threshold. In other embodiments, high-ampacity PON device100B can service a group of any number of branch breakers202, wherein the ampacity of the group of branch breakers202does not exceed the second threshold.

In the preceding, reference is made to various embodiments. However, the scope of the present disclosure is not limited to the specific described embodiments. Instead, any combination of the described features and elements, whether related to different embodiments or not, is contemplated to implement and practice contemplated embodiments. Furthermore, although embodiments may achieve advantages over other possible solutions or over the prior art, whether or not a particular advantage is achieved by a given embodiment is not limiting of the scope of the present disclosure. Thus, the preceding aspects, features, embodiments and advantages are merely illustrative and are not considered elements or limitations of the appended claims except where explicitly recited in a claim(s).

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many other implementation examples are apparent upon reading and understanding the above description. Although the disclosure describes specific examples, it is recognized that the systems and methods of the disclosure are not limited to the examples described herein, but may be practiced with modifications within the scope of the appended claims. Accordingly, the specification and drawings are to be regarded in an illustrative sense rather than a restrictive sense. The scope of the disclosure should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.