The present invention relates, in general, to electrical power metering apparatus and, specifically, to electrical watthour meter socket adapters and watthour meter sockets.
In the electric utility industry, plug-in, socket-type watthour meters are commonly employed to measure electric power consumption at a residential or commercial building establishment. A socket is mounted on a wall of the residence or building and contains terminals which are connected to electric line and electric load conductors. The terminals are also connected to internal conductors within the socket which extend to jaw contacts positioned to receive the blade terminals of a plug-on watthour meter to complete an electric circuit through the watthour meter between the line and load terminals and the conductors.
One type of meter socket has a ring-type cover which includes an outwardly projecting, annular mounting flange surrounding an opening in the cover through which the blade terminals of a watthour meter extend. The mounting flange is sized to mate with a complementary formed mounting flange on the bottom of the watthour meter.
In high power applications, current levels exceed the ratings of commonly available watthour meters. In these applications, current transformers are placed around the incoming line conductors and connected to watthour meter receiving jaw contacts to enable watthour meters to measure load current and provide a scaled power measurement.
A special socket, referred to as a K-series socket, shown in
As also shown in
A cover is mountable over the socket and has an aperture formed in a slidable cover portion for allowing an end portion of the watthour meter to extend therethrough for easy viewing of power measurements. The aperture is mounted in a plate slidably captured on the back of the socket cover. The aperture is offset from the center of the plate such that flipping the plate 180° enables the watthour meter when moved from a lowered operative position to a separate upper inoperative position, to extend through the aperture.
In the inoperative position, the line bus bars on the watthour meter are disengaged from the line bus bar fasteners and moved to a separate spaced row of fasteners, also extending from the line bus bars. However, separate electrically insulting posts are provided in a spaced manner from the load bus bar studs for receiving the load bus bars on the watthour meter in the disconnected position. This disconnects the watthour meter from measurement or service and places it in an out-of-service position.
Attempts to use a watthour meter socket adapter for a plug-in watthour meter in a K-series socket have met with limited success. The size and location of the line conductor insulator blocks, the ground terminal connector and the ground terminal insulator block necessitated socket adapter bus bars having a smaller cross-section than required for current applications up to 400 amps. In addition, additional features and refinements added over time such as cutouts in the sidewall of the socket adapter to accommodate the insulator blocks and ground terminal, make use of the socket adapter difficult without first removing the additional features and refinements.
As is evident from
In electrical power service sites, it frequently becomes necessary to up grade the electrical power service to supply higher current to the customer site. At high current levels, current transformers are employed to provide lower current levels which can be metered by watthour meters. However, such current transformers require special mounting in a socket which increases installation time and results in a higher installation cost.
It is believed that there still is a need for a watthour meter socket adapter which can be successfully employed in a K-series watthour meter socket. It is also desirable to provide a watthour meter socket adapter for mounting a plug-in watthour meter in a K-series meter socket which can be economically constructed with minimal modification to existing watthour meter socket adapter designs. It would also be desirable to provide a current transformer mounting apparatus which fits within an existing K-series meter socket footprint for reduced installation time and costs when it becomes necessary to increase power to a customer site.
A watthour meter socket adapter mounts a plug-in watthour meter in a K-series meter socket.
In one aspect, an electrical power service apparatus includes a meter fitting having an enclosure with line and load electrical power conductor connection terminals and line and load electrical connections for connecting a watthour meter in one of an in-service metering position and an out-of-service, non-metering position with respect to the line and load power conductor connection terminals. Socket adapter means, receiving a plug-in watthour meter, mounts the watthour meter in the normally out-of-service position with respect to the line and load power conductor connection terminals while electrically connecting the watthour meter to the line and load electrical connections in an in-service metering connection.
In another aspect, an electric power service apparatus includes line and load terminals mounted in a socket and receiving electric power line and load conductors. A line bus bar is connected to each line terminal. Upper normally out of service line connections and lower normally in-service line connections are mounted on each line bus bar. A load bus bar is connected to each load terminal. A lower load connection is connected to the load bus bar.
A socket adapter carries jaw contacts for removably receiving blade terminals of a watthour meter. Electric conductors are carried on the socket adapter and extend therefrom to connection ends. The conductors have an overall length to connect the socket adapter conductors to the lower bus bar connections and either of the upper or lower line connections on the line bus bars, to define an in-service metering position of the socket adapter relative to the meter socket even though the socket adapter may be disposed in the normally out-of-service position relative to the meter socket. This enables the socket adapter to receive a watthour meter in a metering position while spacing the socket adapter from a ground terminal insulating block mounted adjacent to a ground terminal in the enclosure.
In the in-service metering position of the socket adapter, the socket adapter is positioned relative to an aperture in the enclosure cover to enable a watthour meter mounted in the socket adapter to extend through the aperture in the cover in the normally out-of-service metering position.
Each of the socket adapter conductors has a first end portion disposed in the socket adapter defining a first plane, a second end portion defining a second plane spaced from the first plane, and an intermediate portion coupling the first and second end portions.
In another aspect, a jumper terminal is mounted on the socket adapter. An electrical conductor extends interiorly of the socket adapter between the terminal and a socket adapter ground terminal. The jumper terminal is connectable in the socket ground terminal when the socket adapter is connected to the line and load connections in the meter socket.
In another aspect, an electrical power service apparatus includes a housing having a mounting surface. Terminal ends of electric power line conductor and electric power load conductors are disposed in the housing in a first service connection position. A mounting plate is mountable on the mounting surface. A plurality of current transformers are mounted on the mounting plate. A busbar extends through each current transformer and has first and second ends spaced from each current transformer. Mounting means are carried on the first and second ends of each bus bar for receiving a terminal end of one of the electric power line and one of the electric power load conductors. The mounting means are disposed in the first service connection position in the housing.
A potential terminal may be mounted on each busbar. Means are also provided for fixing each busbar on the mounting plate. The fixing means includes an electrically insulated standoff disposed between each busbar in the mounting plate.
The disclosed watthour meter socket adapter enables a plug-in watthour meter to be employed in a K-series meter fitting without modification to the socket adapter structure. The socket adapter and the conductors are constructed to define an in-service metering position of the socket adapter relative to the enclosure even though the socket adapter and attached watthour meter are disposed in the normal out-of-service metering position in the enclosure. This enables the socket adapter to uniquely clear the ground terminal insulating block mounted adjacent the ground terminal in the meter fitting without requiring modification, such as cut outs, to the structure of the socket adapter housing which would diminish its integrity.
The socket adapter and the socket adapter conductors are positioned such that the socket adapter clears the ground terminal insulating block mounted adjacent the enclosure ground terminal. The socket adapter is mountable to the existing line and load connections in the K-series meter fitting without substantial modification to the integrity or the structure of the socket adapter housing.
The mounting of current transformers on a mounting plate uniquely enables the current transformers to be installed in the same footprint as metering components in an existing K-series meter fitting for reduced installation time and costs when it becomes necessary to increase current levels supplied to a customer site.
The various features, advantages and other uses of the present invention will become more apparent by referring to the following detailed description and drawing in which:
For clarity in understanding the features and advantages of the present watthour meter socket adapter, a description will be first presented with reference to
As shown in
Individual plate-like line bus bars 30, 32 and 34 are connected at one end to the terminals 24, 26 and 28, respectively, and are secured to the upper block 23 by fasteners 36. The bus bars 30, 32 and 34 each support a first fastener, such as bolts 40, 42 and 44, respectively. The bolts 40, 42 and 44 are arranged in a first row hereafter defined as a first meter mounting position in which the bolts 40, 42 and 44 are positioned for receiving the line bus bars of a watthour meter in a power measuring or metering position.
A second row of second fasteners, such as bolts 46, 48 and 50, are also mounted on and extend from the bus bars 30, 32 and 34, respectively. The fasteners or bolts 46, 48 and 50 are arranged in a second row hereafter referred to as an out of service meter position.
Similar load connections are also mounted on a lower insulating block 27 by fasteners 29 and include terminals 50, 52 and 54 which provide a terminal or connection point for distribution load conductors, not shown. Bus bars 56, 58 and 60 are also mounted on the lower block 27 and are connected at one end to the terminals 52 and 54 respectively. Each bus bar 56, 58 and 60 are secured by fasteners 62 to the lower block 27. Meter mounting fasteners, such as bolts 64, 66 and 58, are respectively carried on each bus bar 56, 58 and 60 and extend therefrom for receiving watthour meter load conductors or bus bars in a power metering position.
In a meter bypass mode of operation, jumper bars or straps 70, 72 and 74 extend between and have opposite ends located adjacent to the individual line bus bars 30, 32 and 34 and the load bus bars 56, 58 and 60 and fixed to the upper block 23 and the lower block 27 by fasteners 36, etc. The ends adjacent to the load bus bars 30, 32, and 34 are electrically coupled to the load bus bars 30, 32, and 34, respectively, by jumper straps 35.
As shown in
Line insulator blocks 76 and 78 are mounted between adjacent line bus bars 30, 32 and 34 to provide sufficient electrical insulation between the high current carrying bus bars 30, 32 and 34. Similar load insulator blocks 80 and 81 are mounted between two of the load bus bars 58 and 60 and between load bus bars 56 and 58, respectively. A ground terminal insulator bracket or block 82 is clipped onto the block 81 as shown in
As shown in
As shown in
Referring now to
As shown in
A mounting flange 153, generally in the same plane as the bottom wall 152, projects radially outward from the sidewall 154.
A plurality of individual jaws are mounted in the bottom wall 152, with the jaw contact portion of each jaw disposed within the interior of the sidewall 154. A strap or blade terminal 171 is connected to each jaw contact and projects through and outward from the bottom wall 152. Ground straps 165 and 167 as well as an insulating shield 169 are also optionally mounted in the socket adapter 150. Further details concerning the ground straps 165 and 167 and the shield 169 may be had by referring to U.S. Pat. Nos. 5,571,031, 6,325,66 and 6,478,589, all of which are assigned to the assignee of the present invention and all of which are incorporated herein in their entirety with respect to the ground straps and the shield.
A plurality of line bus bars, with three bus bars 160, 162 and 164 illustrated in
As shown in
Apertures are formed in the end portions 176 and 182 of each bus bar 160, 162, 164, 166, 168 and 170 for mounting over one of the mounting fasteners in the K-series meter fitting shown in
As shown in
As shown in
An optional cover or housing 190, shown in
The housing 190 includes one or more apertures or slots 192 on opposite sides to allow the bus bars 160, 162, 164, 166, 168 and 170 to extend therethrough. As shown in
Another feature is shown in
The linear portions 172 and 178 of the line bus bars 160, 162 and 164, and the load bus bars 166, 168 and 170 are designed with a specific length to enable the intermediate portions 174 and 180 and the end portions 176 and 180 of each bus bar to clear the line and load insulator blocks and the ground terminal bracket so as to be mountable over the load mounting fastener 64, 66 and 68 in the upper row of line fasteners 46, 48 and 50 which, as described above in conjunction with the prior art socket, as shown in
As shown in
The aperture means also includes a panel or plate 222 which is repositionally mounted on the cover 220 and has a circular aperture 223. The aperture 223 in the panel 222 is longitudinally off center between the ends of the panel 222. This enables the panel 222 to be repositioned in one of two 180° offset or rotated positions relative to the cover 220 thereby moving the aperture 223 in the panel 222 vertically up and down in a normal mounting orientation of the meter fitting so as to enable a portion of the watthour meter mounted in the socket adapter 150 in the meter fitting housing to extend through the aperture 223 in the panel 220 and the aperture 224 in the cover 220 in either the prior art normal in-service position or the out-of-service position. The cover 220 and the panel 222, which are both used in the prior art K-series meter fitting, can be employed with the socket adapter 150. However, the upper position shown in
In the socket adapter and meter position shown in
Referring now to
In both aspects of the socket adapter 150 mounting position shown in
Referring now to
Single or polyphase jaw contacts 256, only one phase of which is shown in
A plurality of bus bars 260, only one of which is shown in
As with the bus bars 160, 162, 164, 166, 168, and 170, described above and shown in
As with the bus bars described in the prior aspect of the socket adapter 150, each bus bar 260 has arcuate or angularly bent intermediate portions 276 and 278 at opposite ends of the linear portion 262. Each of the intermediate portions 276 and 278 transitions into a generally linear or planar end portion 280 and 282, respectively. Apertures 284 are formed in each of the linear end portions 280 and 282 for mounting the end portions 280 and 282 over the mounting fasteners in the K-series meter fitting shown in
Referring now to
In this aspect, a mounting plate 300 is mountable in the meter fitting after all of the components, including the bypass jumper 70, 72 and 74, the line bus bars 30, 32, and 34, the load bus bars 56, 58 and 60 as well as the insulating mounting blocks 23 and 27 and the neutral plate 77 are removed from the meter fitting. Apertures 301 in the mounting plate 300 are alignable with the apertures which originally received the insulating block fasteners 25 and 29. This enables the mounting plate 300 and the components described hereafter which are mounted on the plate 300 to be easily and quickly mounted on the back wall 22 of the meter fitting as a unitary assembly.
The mounting plate 300 supports a plurality of current transformers, with three current transformers 302, 304, and 306 being illustrated by way of example only for a three phase circuit. Only two current transformers are used for single phase power service.
The current transformers 302, 304, and 306 may be of any power size, with 600 amp current capacity current transformers being used by way of example. Each current transformer 302, 304, and 306 in a form of a toroidal wire coil 308 having a through bore 310 extended between opposed side surfaces. The coil 308 is mounted on the mounting or base plate 300 by means of fasteners 312.
By way of example only, removable caps 314 are mounted on each coil 308 to cover current terminals electrically connected to the ends of the coil 308.
Each current transformer 302, 304, and 306 is in the form of a window-style current transformer in that the through bore 310 allows an electrical conductor, typically in the form of a rigid, high current carrying capacity bus bar 322, 324, and 326 to be passed there through. Each bus bar 322, 324, and 326 has studs or bolts mounted at opposite ends for attachment to the line and load conductors in the socket. Thus, the bus bar 322 is provided with a line stud 326 and a load stud 328. The bus bar 324 has a line stud 330 and a load stud 332. The bus bar 326 has a line stud 334 and a load stud 336. Since the mounting plate 300 fits within the existing K-series socket footprint of the back wall 22 shown in
Each bus bar 322, 324, and 326 is fixedly mounted to the base or mounting plate 300 by at least one and, for example only, a pair of standoffs 340 and 342. Each standoff 340 and 342 includes a bolt 344 which extends through an aperture in each bus bar 322, 324, and 326 to secure the bus bar 322, 324, and 326 in a fixed position with respect to the mounting plate 300 and the associated current transformer 302, 304, or 306. An electrically insulating sleeve, such as a GLASTIC J standoff 346 is mounted about each bolt 344 for electrical insulation purposes.
As shown in
In use, when it is necessary to upgrade electrical service with higher current, the base plate 22, if present, or all of the associated meter fitting hardware shown in
As shown in
As also shown in
Since the meter fitting no longer receives a watthour meter, a blank-out plate can be mounted on the cover 220 in place of the apertured plate 222.
Number | Name | Date | Kind |
---|---|---|---|
4516817 | Deters | May 1985 | A |
4547036 | Keglewitsch et al. | Oct 1985 | A |
4553802 | Ruehl | Nov 1985 | A |
4659158 | Sakamoto et al. | Apr 1987 | A |
4883430 | Siemon et al. | Nov 1989 | A |
5033973 | Pruehs et al. | Jul 1991 | A |
5609493 | Cheng et al. | Mar 1997 | A |
5879203 | Egle et al. | Mar 1999 | A |
6015314 | Benfante | Jan 2000 | A |
6099347 | Hoyt et al. | Aug 2000 | A |
6402548 | Ruiz et al. | Jun 2002 | B1 |
6592399 | Robinson et al. | Jul 2003 | B2 |
6663405 | Robinson et al. | Dec 2003 | B1 |
6663422 | Robinson et al. | Dec 2003 | B1 |
6752652 | Robinson | Jun 2004 | B1 |
20030008551 | Chang | Jan 2003 | A1 |
Number | Date | Country | |
---|---|---|---|
20060258204 A1 | Nov 2006 | US |