Patent Publication Number: US-7585034-B2

Title: Power distribution panel with modular inserts

Description:
RELATED APPLICATION 
   This application is a continuation of U.S. patent application Ser. No. 10/319,456 filed on Dec. 13, 2002, the entirety of which is hereby incorporated by reference. 

   FIELD OF THE INVENTION 
   The present invention relates generally to power distribution panels. More particularly, the present invention relates to power distribution panels with modular inserts. 
   BACKGROUND OF THE INVENTION 
   In telecommunication installations, equipment is often mounted in equipment racks. These racks permit greater density and organization of installation for this equipment. To simplify the provision of power to the equipment mounted within a rack, power distribution panels may be mounted in the same rack. These power distribution panels have one or more power input terminals to which higher capacity power supply cables may be attached. Within the panels is circuitry for distributing the current from the power input terminals to one or more power output terminals. From the output terminals, electrical cables may be led to the telecommunications equipment mounted within the rack. The circuits within the power distribution panel may also include circuit protection devices such as circuit breakers or fuses. 
   To maximize the amount of rack space that can be devoted to telecommunications equipment, it is desirable to make the power distribution panels as compact as possible. The compact nature of the panels may make it difficult to access the interior of a panel, for instance, for repairs or routine maintenance. However, removal of a panel from a rack may result in the equipment within that rack being depowered during the repair or maintenance. Removing the equipment and any circuits the equipment may support from service costs the service provider in terms of lost revenue. 
   Many of the power distribution panels include two or more discrete power distribution circuits within a single panel. Often, only one of these circuits requires repair or maintenance, but both circuits must be taken offline when the panel is removed from the rack. Improvements to power distribution panels are desirable which allow individual circuits within a power distribution panel to be accessed for repair or maintenance without removing all circuits of the panel from service. 
   SUMMARY OF THE INVENTION 
   The present invention relates to a power distribution panel where the power distribution components and circuitry are mounted in a removable module. The module can be removed from the power distribution panel without disconnecting any other modules within the panel. 
   The present invention further relates to a module including the components and circuitry to distribute power to other devices. The module is adapted to be removably mounted within a chassis to form a power distribution panel. The module may be inserted or removed from the chassis without disrupting other modules which are mounted to the chassis. 
   The present invention further relates to a method of replacing a power distribution module of a power distribution panel. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate several aspects of the invention and together with the description, serve to explain the principles of the invention. A brief explanation of the drawings is as follows: 
       FIG. 1  is a front perspective view of a power panel in accordance with the present invention. 
       FIG. 2  is a front perspective view of the power panel of  FIG. 1 , with one of the modules exploded. 
       FIG. 3  is a front view of the power panel of  FIG. 1 . 
       FIG. 4  is a rear view of the power panel of  FIG. 1 . 
       FIG. 5  is a top view of the power panel of  FIG. 1 . 
       FIG. 6  is a bottom view of the power panel of  FIG. 1 . 
       FIG. 7  is a first side view of the power panel of  FIG. 1 . 
       FIG. 8  is a second side view of the power panel of  FIG. 1 . 
       FIG. 9  is a front view of one of the modules inserted in the power panel of  FIG. 1 . 
       FIG. 10  is a rear view of the module of  FIG. 9 . 
       FIG. 11  is a top view of the module of  FIG. 9 . 
       FIG. 12  is a first side view of the module of  FIG. 9 . 
       FIG. 13  is a second side view of the module of  FIG. 9 . 
       FIG. 14  is a schematic diagram of the circuitry included in the module of  FIG.9 . 
       FIG. 15  is a front view of the chassis of the power panel of  FIG. 1  with no modules inserted. 
       FIG. 16  is a rear view of the chassis of  FIG. 15 . 
       FIG. 17  is a top view of the chassis of  FIG. 15 . 
       FIG. 18  is a first side view of the chassis of  FIG. 15 . 
       FIG. 19  is a second side view of the chassis of  FIG. 15 . 
       FIG. 20  is a rear perspective view of a second embodiment of a power panel in accordance with the present invention. 
       FIG. 21  is a rear perspective view of the power panel of  FIG. 20 , with one of the modules exploded. 
       FIG. 22  is a front view of the power panel of  FIG. 20   
       FIG. 23  is a rear view of the power panel of  FIG. 20 . 
       FIG. 24  is a top view of the power panel of  FIG. 20 . 
       FIG. 25  is a bottom view of the power panel of  FIG. 20 . 
       FIG. 26  is a first side view of the power panel of  FIG. 20 . 
       FIG. 27  is a second side view of the power panel of  FIG. 20 . 
       FIG. 28  is a front view of one of the modules of the power panel of  FIG. 20 . 
       FIG. 29  is a rear view of the module of  FIG. 28 . 
       FIG. 30  is a top view of the module of  FIG. 28 . 
       FIG. 31  is a first side view of the module of  FIG. 28 . 
       FIG. 32  is a second side view of the module of  FIG. 28 . 
       FIG. 33  is a front view of a chassis of  FIG. 15  with an alternative universal back plate. 
       FIG. 34  is a rear view of the chassis of  FIG. 33 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Reference now will be made in detail to exemplary aspects of the present invention that are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
   Power distribution panels such as panel  10  shown in  FIGS. 1 and 2  may be used to provide power for telecommunications or other electronic equipment mounted in equipment racks. The telecommunications or other electronic equipment is may be sensitive to fluctuations in the electrical power being supplied, and damaged by over-current or over-voltage conditions. Thus, panel  10  includes a plurality of circuit protection devices  12  mounted to a front face  14 . Panel  10  includes two separate power busses, one in each of two modules  16  which on each side of panel  10 . Each of the modules  16  shown in  FIG. 1  has four circuit protection devices  12 , which as shown are TPA fuses, each fuse  12  providing over-current and over-current protection to one of four power supply circuits within each module  16 . 
   Each module  16  shown in  FIGS. 1 and 2  includes two sets of power input terminals  22  for receiving power from two power sources. Each set of terminals  22  are electrically linked by circuitry within module  16  through fuses  12  to a plurality of power output terminals  24 . The electrical connections between the different components within module  16  are shown in  FIG. 14 , which is a circuit diagram for module  16 . Additional details of modules  16  are described below with regard to  FIGS. 9 through 14 . 
   While high current in the power supply circuit may damage the equipment, low voltage conditions may also adversely impact the function of the equipment. Thus, each power input terminal  22  is connected with a power input contactor  26  and also connected to a low voltage detection circuit on a circuit board  70 . When one of the low voltage detectors on board  70  detects a low voltage condition in one of the power inputs, that detector generates an alarm and illuminates an associated low voltage alarm lamp  18  also mounted to front face  14  to indicate which power input terminal  22  is connected to a low voltage source. At the time the alarm is generated, the low voltage detector signals contactor  26  which in turn disconnects the input source from fuses  12  and power output terminals  24 . Also mounted on front face  14  is a power indicator lamp  20  associated with each power input terminal  22  to indicate if power is being supplied through the associated input terminal. 
   Panel  10  includes a chassis  38  with a top  28 , a bottom  30  and a pair of sides  32  which cooperate to define an interior  34 . Attached along each side  32  is a mounting flange  36 . Flange  36  facilitates the mounting of panel  10  to an equipment rack or other structure adjacent electronic equipment requiring power management. In top  28  adjacent a front edge  42  are a plurality of ventilation slots  40 . Slots  40  are angled approximately forty-five degrees from front edge  42 . Slots  40  provide an exit for heated air to escape interior  34 . The angling of slots  40  aids in controlling of flame spread should the components within panel  10  become overheated. Angling of ventilation slots for telecommunications equipment is disclosed in further detail in commonly-owned U.S. application Ser. No. 09/725,339, the disclosure of which is incorporated herein by reference. Additional details of chassis  10  are provided below with regard to  FIGS. 15 through 19 . 
   Referring now to  FIGS. 4 ,  15  and  16 , panel  10  includes a rear wall  44  which further defines interior  34  is conjunction with top  28 , bottom  30  and sides  32 . A pair of openings  46  are defined in rear wall  44 . Power input connectors  22  and power output connectors  24  extend through openings  46 . Also defined in rear wall  44  is a pair of openings  50  through which a plurality of alarm connectors  48  extend. Alarm connectors  48  allow remote monitoring of the status of fuses  20  in module  16 . Mounted to rear wall  44  between openings  46  are ground posts  52  which provide a common ground source that can be used to ground an equipment rack or other equipment mounted to a rack. A plurality of removable fasteners  54  extend through front face  14  of module  16  serve to releasably fasten module  16  to panel  10 . More or fewer fasteners  54  may be included to fasten module  16  to panel  10  but all fasteners should be accessible from the front or the rear of panel  10  and not require access to the top or bottom of panel  10 . This positioning of fasteners  54  will permit modules  16  to be removed and inserted into panel  10  without removal of panel  10  from an equipment rack or removal of equipment mounted in such a rack adjacent above or below panel  10 . 
   Referring now to  FIGS. 5 and 6 , a plurality of ventilation slots  41  are located in bottom  30  adjacent a rear edge  43 . Slots  41  are angled similarly to slots  40  in top  28 . The combination of slots  41  adjacent rear edge  43  and slots  40  adjacent front edge  42  promote a cross ventilation airflow path within panel  10 , as described in the above-referenced commonly-owned application. 
   Referring now to  FIGS. 9 through 13 , module  16  includes a tray  68  which forms the floor of module  16 . Front wall  14  extends vertically from one end of tray  68 . On the opposite end of tray  68  is a vertical rear wall  56 . Front wall  14 , rear wall  56  and tray  68  cooperate to define an interior  55  of module  16 . The components of module  16  are mounted within interior  55  to one of tray  68 , front wall  14  or rear wall  56 . Front wall  14  includes fastener openings  58  in a pair of mounting flanges  72  which extend from either side of front wall  14 . The maximum width of tray  56  is defined by a pair of opposing sides  74 , which also form slide rails for mounting module  16  within module  10 . 
   Each power input terminal  22  includes a housing  64  with a central dividing wall  66 . On opposite sides of the dividing wall  66  are a pair of battery connector posts  60  and a pair of return connectors posts  62 . The battery and return connectors both use a pair of posts  60  and  62 , respectively, to improve contact with a cable from a power source and aid in the transmission of power through terminal  22 . Posts  60  and  62  extend through power input terminal  22  and through rear wall  56  into interior  55 . Circuitry (see  FIG. 14 ) links posts  60  and  62  to contactors  26 , power lamps  20 , fuses  12 , and to power output terminals  24 . Each power output terminal  24  includes a return post  76  and a battery post  78 . The circuitry may include busbars, wires or other types of electrical conductors which will aid in the delivery and distribution of electrical current between input terminals  22  to output terminals  24 . 
   Within module  16  is circuit board  70  which includes logic circuits for detecting low voltage conditions in the power being input through input terminals  22  and for signaling a low voltage alarm and triggering contactors  26  to break the circuit if a low voltage condition is detected. Board  70  is also linked to fuses  12  for the purposes of triggering a fuse alarm which might signal a problem or interruption of power delivered through power output connectors  24 . In the event of a low voltage alarm, circuit board  70  also triggers lamp  18  to be illuminated while the shutting off the input power from terminal  22  will also shut off the associated power lamp  20 . In the event of a fuse alarm, circuit board  70  would send a signal through alarm connectors  48  to a remote monitoring system. 
   Tray  68  also includes a plurality of ventilation slots  80 , shown in  FIG. 11 . When module  16  is inserted within a chassis  38  as part of a panel  10 , slots  80  are positioned above and angled similarly to slots  41  of bottom  30 . This position and orientation aids in improving airflow through slots  41  and slots  80 , across the components of module  16  and out of panel  10  through slots  42  in top  28 . 
   As discussed above,  FIG. 14  shows diagrammatically the circuitry connecting the components of module  16 . It is understood that a variety of conductors and methods can be used to carry the current between the components in the manner illustrated in  FIG. 14 , provided that all conductors must fit within interior  55  of module  16  to that module  16  may be mounted within chassis  38  to assemble a panel  10 . 
   As shown, module  16  has a pair of power input terminals  22  each of which provides power to two output terminals  24  through two fuses  12 . Panel  10  includes two modules  16 . Thus, panel  10  can receive power from up to four different power sources and provide power to up to eight different devices. Each device receiving power from panel  10  receives power through a separate circuit including circuit protection in the form of a fuse  12 . It is anticipated that other configurations and arrangements of modules for use with panel  10  may be provided with more or fewer input and output terminals. These terminals may be connected with circuitry having different types of circuit protection devices, such as different fuse types, or circuit breakers. The circuitry may or may not include fuse alarms or low voltage detectors and alarms. Alternative power panels may have more or fewer modules. These various alternative embodiments are within the concept of the present invention. 
   Referring now to  FIGS. 15 through 19 , chassis  38  is illustrated in further detail. Openings  46  and  50  are defined in rear wall  44 . A central support  82  extends between top  28  and bottom  30  and receives several fasteners  54  for mounting modules  16  within interior  34 . One of the modules  16  is inserted into interior  34  through an opening  86  defined by front edge  42  of top  28 , a front edge  88  of bottom  30 , a mounting flange  90  extending from one of the sides  32  and central support  82 . Central support  82  and flanges  90  are located adjacent front edges  88  and  42 . Edges  74  of tray  68  are received in a pair of guide rails  84  within interior  34 . Each guide rail  84  is positioned adjacent bottom  30  on either side of opening  86  and extends generally from front edge  88  to rear edge  43 . Guide rails  84  position module  16  vertically within interior  34  so that input and output terminals  22  and  24  are correctly located to extend through opening  46  and to ensure that openings  58  of module  16  are properly positioned to receive fasteners  54 . 
   When fully inserted within interior  34 , as shown in the earlier FIGS., module  16  will be positioned with one flange  72  adjacent mounting flange  90  and one adjacent central support  82 . Fasteners  54  can be inserted through openings  58  of flanges  72 . In this inserted position, power input terminals  22  and power output terminals  24  extend through opening  46 , while alarm connectors  48  extend through opening  50 . 
   Referring now to  FIGS. 20 through 32 , an alternative power panel  110  with a pair of alternative modules  116  is shown. Panel  110  and module  116  are configured similarly to panel  10  and module  16 , with several distinctions noted below. Module  116  includes a single power input terminal  22  and ten power output terminals  24 . A single contactor  26  is mounted to module  116  and linked to a low voltage detection circuit on board  70  to monitor the power input to module  116  through input terminal  22 . Module  116  includes ten fuses  112  mounted to front face  14  along with a single low voltage alarm lamp  18  and a single power lamp  20 . Fuses  112  are GMT fuses. 
   Thus configured, module  116  can receive power from a single source and distribute the power through circuitry into ten individually protected circuits to a total of ten devices. With two modules  116  installed, panel  110  can supply power to a total of twenty devices. Each input terminal  22  includes housing  64  with central wall  66  separating battery posts  60  from return posts  62 . Each output terminal  24  includes a return post  76  and a battery post  78 . 
   Rear face  144  of an alternative chassis  138  includes an opening  146  for each module  116  to permit output terminals  24  to extend through and an opening  147  to permit input terminals  22  to extend through. Opening  50  and ground posts  52  are sized and configured similarly to rear face  44 . The remainder of chassis  138  is substantially similar to chassis  38 , described above. 
   Mounted to front face  114  of module  116  is a fuse alarm lamp  19  to provide a visual indication of the presence of a fuse alarm. Circuit board  70  would illuminate lamp  19  when a fuse alarm is sent to the remote monitoring system through alarm connector  48 . 
   Panels  10  and  110  permit the repair or replacement of either of the two modules  16  or  116 , respectively, without disturbing the mounting of panel  10  or  110 , or the other module. Modules  16  and  116  may be removed and replaced from the front of panel in which it is mounted. For example, to replace one of the modules  16  mounted in panel  10 , the power supply cables connected to power input connectors  22  of module  16  to be replaced would be detached, as would any cables connected power output connectors  24  to other devices. Alarm cables attached to alarm connectors  48  would also need to be detached. The cables connected to the adjacent module  16  would not need to be disturbed and the equipment which the other module  16  is provided power to would not need to be taken offline and depowered. Fasteners  54  would be removed from openings  58  on flanges  72  of the module  16  being replaced. The module can then be withdrawn from interior  34  through opening  86  in the front of panel  10 . 
   A similarly configured replacement module  16  can then be placed in opening  86  with edges  74  within guide rails  84  and slide fully into panel  10 . Flanges  72  would be adjacent central support  82  and side flanges  90  so that fasteners  54  can be inserted through openings  58  and engage panel  10  to hold module  16  in place with interior  34 . Power cables can then be connected to power output terminals  24 , the alarm cables connected to alarm connectors  48  and power cables connected to power input terminals  22 . The new module  16  is now in service and can be used to provide power to other devices. Note that this module replacement was performed without disturbing the power supplied to devices by the adjacently mounted module  16  and without dismounting panel  10  from whatever mounting structure panel  10  might be installed in. 
   Referring now to  FIGS. 33 and 34 , a second alternative chassis  238  includes a second alternative back plate  244 . Back plate  244  is configured with openings  146  sized to receive input terminals  22  and output terminals  24  of either module  16  or module  116 , as well as other modules with different configurations of input terminals and output terminals. A portion  150  of openings  146  of back plate  244  is provided for alarm connectors  48  to extend through. Back plate  244  also includes common ground posts  52 . Due to the desire to have back plate  244  receive a variety of different configuration modules, a greater degree of flexibility of installation is provided by chassis  238 . 
   It should be noted that modules intended for use with chassis  238  including back plate  244  will preferably include marking on the module to indicate the nature and capacity of the components on the module, as well as the configuration of alarm connections  48 . It should also be noted that chassis  38 ,  138  and  238  are shown configured and sized to occupy two rack units on a telecommunication rack, so that the overall chassis height does not exceed 3.5 inches. It is anticipated that the present invention may be increased or decreased in height as necessary for the particular constraints of the installation and the amount of power to be distributed to other equipment by panel  10 . 
   With regard to the foregoing description, it is to be understood that changes may be made in detail, especially in matters of the construction materials employed and the shape, size and arrangement of the parts without changing the scope of the present invention. It is intended that the specification and depicted aspects be considered exemplary only, with the true scope and spirit of the invention being indicated by the broad meaning of the following claims.