Abstract:
An uninterruptible power supply (“UPS”) includes an input module having a plurality of inputs, and at least one jumper element configured to selectively couple at least one input of the plurality of inputs to at least one other input of the plurality of inputs. The plurality of inputs and the at least one jumper element may be constructed and arranged to selectively achieve the following configurations: single power feed, single phase input and single phase output; dual power feed, single phase input and single phase output; single power feed, three phase input and single phase output; dual power feed, three phase input and single phase output; single power feed, three phase input and three phase output; and dual power feed, three phase input and three phase output. Other embodiments and methods of selectively achieving multiple power configurations are also disclosed.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   Embodiments of the present invention are directed to power inputs and outputs used in a power system, and more particularly to a power input and a power output that may be selectively configured to accommodate changes in the power requirements of an uninterruptible power supply. 
   2. Discussion of Related Art 
   The use of an uninterruptible power supply or “UPS” to provide power to a critical load is well known in the art. The UPS is designed to protect electronic equipment from utility power blackouts, brownouts, sags and surges. The UPS may also protect electronic equipment from small utility fluctuations and large disturbances. In most configurations, the UPS provides battery backup until utility power returns to safe levels or the batteries are fully discharged. Known uninterruptible power systems include on-line UPSs and off-line UPSs. On-line UPSs provide conditioned AC power as well as backup AC power upon interruption of a primary source of AC power. Off-line UPSs typically do not provide conditioning of input AC power, but do provide backup AC power upon interruption of the primary AC power source. On-line UPSs of the type described above are available from American Power Conversion Corporation, West Kingston, R.I. under a variety of different trade names. In certain configurations, a UPS may include an input circuit breaker/filter, a rectifier, a control switch, a controller, a battery, an inverter, and a bypass switch. The UPS also may include an input for coupling to an AC power source and an output for coupling to a load. 
   The on-line UPS as described may be configured to operate as follows. The circuit breaker/filter receives input AC power from the AC power source through the input, filters the input AC power and provides filtered AC power to the rectifier. The rectifier rectifies the input voltage. The control switch receives the rectified power and also receives DC power from the battery. The controller determines whether the power available from the rectifier is within predetermined tolerances, and if so, controls the control switch to provide the power from the rectifier to the inverter. If the power from the rectifier is not within the predetermined tolerances, which may occur because of brownout or blackout conditions, or due to power surges, for example, then the controller controls the control switch to provide the DC power from the battery to the inverter. The inverter of the UPS receives DC power and converts the DC power to AC power and regulates the AC power to predetermined specifications. Depending on the capacity of the battery and the power requirements of the load, the UPS can provide power to the load during brief power source dropouts or for extended power outages. The bypass switch is used to provide a bypass of UPS circuitry to provide the input power directly to the output. The bypass switch may be controlled by the controller to provide bypass of the UPS circuitry upon a failure condition of the UPS. 
   To provide further power redundancy, it is known to use a second power source to supply power to a bypass switch of a UPS from a second source of AC power. Systems of this type are often referred to as dual main systems, which are similar to the UPS described above except that it includes a second input to couple to a second power supply. The dual main UPS may include a bypass switch that selectively couples the second input directly to the output of the UPS. In dual main systems, typically, a utility power source is coupled to the first power input of the system and a backup power source, such as a generator or utility power from a different grid, is coupled to the second power input of the system. Upon failure of the utility power source, the power system is able to continue to provide power to a load using the battery mode of operation of the UPS, while the generator is powered on and brought to full output voltage. Once the generator is on line, the power system can continue to provide output power in a bypass mode for an extended period of time from the generator. 
   Power inputs and outputs for such systems are usually selected based on the user requirements for the particular UPS. For example, for systems requiring single phase input and single phase output, a UPS is selected to meet this requirement. Similarly, for systems requiring either three phase input and single phase output, or any other combination of input and output phases, a UPS meeting this requirement is selected. If power requirements change, a user must acquire a different UPS to meet the new requirement. 
   SUMMARY OF THE INVENTION 
   An aspect of the invention may be directed to an uninterruptible power supply (“UPS”) comprising an input module including a plurality of inputs, and at least one jumper element configured to selectively couple at least one input of the plurality of inputs to at least one other input of the plurality of inputs. The plurality of inputs and the at least one jumper element may be constructed and arranged to selectively achieve the following configurations: single power feed, single phase input and single phase output; dual power feed, single phase input and single phase output; single power feed, three phase input and single phase output; dual power feed, three phase input and single phase output; single power feed, three phase input and three phase output; and dual power feed, three phase input and three phase output. 
   Embodiments of the UPS may include providing the plurality of inputs with three primary inputs L 1 , L 2  and L 3  and three bypass inputs B 1 , B 2  and B 3 . The at least one jumper element may comprise a bypass shorting jumper element configured to couple the three bypass inputs B 1 , B 2  and B 3  to one another to achieve the dual power feed, three phase input and single phase output configuration. The at least one jumper element further may comprise a main shorting jumper element configured to couple the three primary inputs L 1 , L 2  and L 3  to one another to achieve the dual power feed, single phase input and single phase output configuration. The at least one jumper element further may comprise a first secondary jumper element configured to couple the primary input L 1  and the bypass input B 1  to one another to achieve the single power feed, three phase input and single phase output configuration. The at least one jumper element further may comprise a first secondary jumper element configured to couple the primary input L 1  and the bypass input B 1  to one another, a second secondary jumper element configured to couple the primary input L 2  and the bypass input B 2  to one another, and a third secondary jumper element configured to couple the primary input L 3  and the bypass input B 3  to one another to achieve the single power feed, single phase input and single phase output configuration. The at least one jumper element may comprise a first secondary jumper element configured to couple the primary input L 1  and the bypass input B 1  to one another, a second secondary jumper element configured to couple the primary input L 2  and the bypass input B 2  to one another, and a third secondary jumper element configured to couple the primary input L 3  and the bypass input B 3  to one another to achieve the single power feed, three phase input and three phase output configuration. The dual feed, three phase input and three phase output configuration may be achieved without the at least one jumper element coupled to any of the plurality of inputs. The plurality of inputs further may comprise a neutral input and a ground input, and wherein each input of the plurality of inputs comprises at least one screw lug configured to secure a wire to each input. The ground input may comprise at least two screw lugs positioned adjacent one another. The at least one jumper element may include at least one blocking segment to selectively block the coupling of a wire to at least one of the plurality of inputs. The UPS further may comprise an output module including a plurality of outputs and an output module jumper element configured to couple at least two outputs of the plurality of outputs to one another. The plurality of outputs may comprise outputs L 1 , L 2  and L 3 . The plurality of outputs further may comprise a neutral output and a ground output. The jumper element further may couple the neutral output to at least one of the plurality of outputs. The UPS further may comprise a battery pack power distribution unit coupled to one of the plurality of outputs of the output power module. 
   Another aspect of the invention may be directed to a method of selectively achieving multiple power configurations in an uninterruptible power supply of the type comprising an input module having three primary inputs L 1 , L 2  and L 3  and three bypass inputs B 1 , B 2  and B 3 , and at least one jumper element configured to selectively couple at least one input of the plurality of inputs to at least one other input of the plurality of inputs. The at least one jumper element may comprise a main shorting jumper element configured to couple the three primary inputs L 1 , L 2  and L 3  to one another, a bypass shorting jumper element configured to couple the three bypass inputs B 1 , B 2  and B 3  to one another, a first secondary jumper element configured to couple the primary input L 1  to the bypass input B 1 , a second secondary jumper element configured to couple the primary input L 2  to the bypass input B 2 , and a third secondary jumper element configured to couple the primary input L 3  to the bypass input B 3 . In one embodiment, the method may comprise installing the bypass shorting jumper element to achieve a dual power feed, a three phase input and a single phase output configuration. 
   In other embodiments, the method further may comprise installing the main shorting jumper element to achieve a dual power feed, a single phase input and a single phase output configuration. The method further may comprise installing the first secondary jumper element to achieve a single power feed, a three phase input and a single phase output configuration. The method further may comprise installing the main shorting jumper element, the first secondary jumper element, the second secondary jumper element and the third secondary jumper element to achieve a single feed, a single phase input and a single phase output configuration. In another embodiment, the method may further comprise selectively blocking the coupling of a wire to at least one of the plurality of inputs using one of the jumper elements. 
   A further aspect of the invention may be directed to a method of selectively achieving multiple power configurations in an uninterruptible power supply of the type comprising an input module having three primary inputs L 1 , L 2  and L 3  and three bypass inputs B 1 , B 2  and B 3 , and at least one jumper element configured to selectively couple at least one input of the plurality of inputs to at least one other input of the plurality of inputs. The at least one jumper element may comprise a first secondary jumper element configured to couple the primary input L 1  to the bypass input B 1 , a second secondary jumper element configured to couple the primary input L 2  to the bypass input B 2 , and a third secondary jumper element configured to couple the primary input L 3  to the bypass input B 3 . In one embodiment, the method may comprise installing the first secondary jumper element, the second secondary jumper element and the third secondary jumper element to achieve a single power feed, a three phase input and a three phase output configuration. 
   Embodiments of the method may include selectively blocking the coupling of at least one of the plurality of inputs. 
   Yet another aspect of the invention may be directed to an uninterruptible power supply (“UPS”) comprising an input module including a plurality of inputs and means to selectively couple the inputs to achieve the following configurations: single power feed, single phase input and single phase output; dual power feed, single phase input and single phase output; single power feed, three phase input and single phase output; dual power feed, three phase input and single phase output; single power feed, three phase input and three phase output; and dual power feed, three phase input and three phase output. 
   Embodiments of the UPS may comprise an output module including a plurality of outputs and an output module jumper element configured to couple at least one output of the plurality of outputs to at least one other output of the plurality of outputs. The plurality of outputs may comprise terminals L 1 , L 2  and L 3 . In one embodiment, the UPS further may comprise a battery pack power distribution unit coupled to one of the plurality of outputs of the output power module. In another embodiment, the UPS further may comprise an alternate power source coupled directly to the output module. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a better understanding of the present invention, reference is made to the drawing figures which are incorporated herein by reference and in which: 
       FIG. 1  is an exploded perspective view of an uninterruptible power supply (“UPS”) having a input power module and an output power module of embodiments of the invention removed from a main body of the UPS; 
       FIG. 2  is a rear elevational view of the UPS having the input power module and the output power module secured to the main body of the UPS; 
       FIG. 3  is a rear perspective view of the input power module having a cover assembly removed to reveal an interior of the input power module; 
       FIG. 4  is a front exploded perspective view of the input power module with the cover assembly shown prior to its attachment to a housing of the input power module; 
       FIG. 5  is a front elevational view of the input power module; 
       FIG. 6  is a cross-sectional view of a wire connected to a screw lug; 
       FIG. 7A  is a rear perspective view of the output power module having a cover removed to reveal an interior of the output power module; 
       FIG. 7B  is a front perspective view of the output power module shown in  FIG. 7A . 
       FIG. 8  is a top plan view of the input power module showing a single feed, a single phase input and a single phase output configuration; 
       FIG. 9  is a top plan view of the input power module showing a dual feed, a single phase input and a single phase output configuration; 
       FIG. 10  is a top plan view of the input power module showing a single feed, a three phase input and a single phase output configuration; 
       FIG. 11  is a top plan view of the input power module showing a dual feed, a three phase input and a single phase output configuration; 
       FIG. 12  is a top plan view of the input power module showing a single feed, a three phase input and a three phase output configuration; 
       FIG. 13  is a top plan view of the input power module showing a dual feed, a three phase input and a three phase output configuration; 
       FIG. 14  is a top plan view of the output power module showing a single phase hardwire output configuration; 
       FIG. 15  is a top plan view of the output power module showing a three phase hardwire output configuration; 
       FIG. 16  is a top plan view of the output power module showing a single phase output configuration that is connected to a battery pack power distribution unit; and 
       FIG. 17  is a schematic block diagram of the UPS of embodiments of the invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   For the purposes of illustration only, and not to limit the generality, the present invention will now be described in detail with reference to the accompanying figures. This invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” “having,” “containing,” “involving,” and variations thereof herein, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. 
   Embodiments of the invention provide an input module and an output module for use in a UPS, such as the UPS configurations described above. Embodiments of the invention can be used in systems and electronic devices, other than UPSs, that require electrical connections. Still other applications of embodiments of the invention are envisioned. 
   Referring to  FIGS. 1 and 2 , an uninterruptible power supply (“UPS”) is shown and generally indicated at  10 . The UPS  10  can be a domestic or an international UPS model sold by American Power Conversion Corporation of West Kingstown, R.I., the assignee of the present invention. As discussed above, a UPS assists in providing a substantially consistent flow of power from a power source to electronic devices that are connected to the UPS. The UPS  10  includes a main body  12  having a plurality of functional components housed within the main body.  FIGS. 1 and 2  illustrate a rear panel  14  of the main body  12  adapted to receive a power terminal input module generally indicated at  16  and a power terminal output module generally indicated at  18 . The purpose of the input module  16  and the output module  18  is to provide electrical connections for peripheral electrical devices, while keeping wires of such devices sufficiently separated. For example, peripheral electrical devices can include, but are not limited to, servers, HVAC devices, refrigeration devices, control panels and motor controls, which are operated under the control of a controller (not shown in  FIGS. 1 and 2 ) provided within the UPS. 
   Referring to  FIGS. 3 and 4 , the input module  16  that can be used in a UPS is shown in perspective view with a pair of top covers  20 ,  22  removed in  FIG. 3  to show the interior of the module. As shown, the input module  16  includes a housing generally indicated at  24  having a bottom wall  26 , two side walls  28 ,  30 , a front  32  and a back wall  34 , which together define an interior region of the housing. An insert  36 , which may be fabricated from any suitable hard plastic or polymeric material, is disposed within the interior region of the housing  24  adjacent the front  32  of the housing. The insert  36  may be suitably secured to the housing  24  by screw fasteners (not shown) and/or integrated tabs that snap fit within openings or perforations formed in the bottom wall  26  and side walls  28 ,  30  of the housing. Referring to  FIG. 4 , the arrangement is such that the two top cover panels  20 ,  22 , when secured to the housing in the manner shown, e.g., by screw fasteners  38 , completely enclose the interior region of the housing  24 . 
   As best shown in  FIGS. 4 and 5 , the insert  36  is configured at the front  32  of the housing  24  with seven socket terminals, each indicated at  40 , and one pin terminal  42 . The front  32  of the housing  24  of the input module  16  may be inserted and plugged into an input receptacle  44  provided in the UPS  10  in the manner illustrated in  FIGS. 1 and 2 . As shown in  FIG. 5 , the six left-hand socket terminals  40   a ,  40   b ,  40   c ,  40   d ,  40   e  and  40   f  are adapted to transfer a main alternating current (“AC”) source and an auxiliary AC source to the UPS. The remaining socket terminal  40   g  and the right-hand pin terminal  42  are configured to connect a neutral wire and earth ground wires (both not shown), respectively, to the UPS  10 . 
   The interior region of the housing  24  of the input module  16  may be further configured to have eight stalls, each stall defining an electrical connection terminal. Specifically, the terminals are designated L 1 , L 2 , L 3 , B 1 , B 2 , B 3 , N and G in FIGS.  3  and  8 - 13 , with the six right-hand terminals (designated B 3 , B 2 , B 1 , L 1 , L 2  and L 3  from right to left in FIGS.  3  and  8 - 13 ) being adapted to receive a main AC source and an auxiliary AC source in the manner described in greater detail below. Each of the six terminals L 1 , L 2 , L 3 , B 1 , B 2  and B 3  have a screw lug each indicated at  46  configured to secure an electrical wire or cable (not shown) in a well-known manner. The electrical wire may be crimped, screwed or otherwise fastened into a contacting position with the screw lug. For electrical and mechanical connection, the screw lugs  46  are substantially exposed within their respective stalls. As shown, the six right-hand terminals (i.e., B 3 , B 2 , B 1 , L 1 , L 2  and L 3  in FIGS.  3  and  8 - 13 ) may be positioned adjacent respective socket terminals (i.e.,  40   a ,  40   b ,  40   c ,  40   d ,  40   e  and  40   f , respectively). The two left-hand terminals (i.e., N and G as shown in  FIGS. 8-13 ) are adapted to receive neutral and ground wires (not shown) and correspond to the remaining socket terminal (i.e.,  40   g ) and the pin terminal (i.e.,  42 ) described above. As shown, the neutral N terminal includes two screw lugs  48 ,  50  and the ground terminal G includes four screw lugs  52 ,  54 ,  56  and  58 . The provision of two screw lugs  48 ,  50  within the neutral terminal N and four screw lugs  52 ,  54 ,  56  and  58  within the ground terminal G enables the connection of the neutral and ground wires from both AC sources (main and auxiliary) with the forward screw lug (e.g., screw lug  52 ) secured to the bare wire and the rearward screw lug (e.g., screw lug  54 ) secured to the insulation in the manner illustrated in  FIG. 6 . The securement of the rearward screw lug to the insulation may provide strain relief to the wire or cable. 
   Referring back to  FIG. 3 , in a certain embodiment, the back wall  34  includes a back wall portion  60  and two side wall portions  62 ,  64 , each side wall portion extending at an angle from opposite sides of the back wall portion. The back wall  34  has four circularly-shaped, perforated cutouts, each indicated at  66 , formed therein. As shown, two cutouts  66  are formed on the back wall portion of the housing and each side wall portion ( 62 ,  64 ) has a cutout  66  formed therein. The cutouts  66  are provided to be selectively removed from the back wall  34  of the housing  24  to enable cables or wires to pass therethrough for connection to the terminals. Three tabs  68 ,  70  and  71  are provided to secure the input module  16  to the UPS  10  in the manner shown in  FIG. 2 . 
   Referring to  FIGS. 7A and 7B , the output module  18  includes a housing generally indicated at  72  having a front wall  74 , two side walls  76 ,  78 , a top wall  80  and a bottom  82 , which together define an interior region of the housing. The arrangement is such that a cover  84 , when secured to the housing  72 , completely encloses the interior region of the housing. Screw fasteners  86  may be provided to secure the cover  84  to the housing  72 . The output module  18  is configured with seven pin terminals  87  provided in a formation  88  projecting from the front wall  74  of the housing, which is pluggable into a socket  90  provided in the UPS  10  ( FIG. 1 ). An insert  92  is disposed within the interior region of the housing  72 . The insert  92  may be suitably secured to the housing  72  by screw fasteners (not shown) and/or tabs that snap fit within openings or perforations formed in the front wall  74  and/or the side walls  76 ,  78  of the housing. The pin terminals are designed to receive conditioned power from the UPS. 
   The interior region of the housing  72  of the output module  18  may be further configured to have five stalls, each stall defining an electrical connection terminal, which correspond to five of the seven pin terminals described above. Specifically, the insert  92  of the output module may be configured with five socket terminals corresponding to terminals L 2 , L 2 , L 3 , N and G shown in  FIGS. 14-16 . In one embodiment, and as described above, the front wall  74  of the housing  72  may be configured with the seven pin terminals within the formation  88  that enable the output module to be inserted and plugged into the output socket receptacle  90  provided in the UPS in the manner illustrated in  FIG. 1 . Tabs, each indicated at  94 , may be provided to secure the output module  18  to the UPS  10 . 
   As described above, the insert  74  is provided with five terminals, which correspond to five of the seven pin terminals that are plugged into the UPS  10 , each terminal having a screw lug  96  configured to secure an electrical wire or cable (not shown), which is connected to a device, such as a computer, monitor, printer, server, etc., that is coupled to the UPS. As with the input module  16 , the electrical wire may be crimped, screwed or otherwise fastened into a contacting position with the screw lug  96 . For electrical and mechanical connection, the screw lugs  96  are substantially exposed within their respective stalls. The three right-hand terminals L 1 , L 2  and L 3  may be configured to receive three phase wires. The two left-hand terminals N and G are adapted to receive neutral and ground wires, respectively. This aspect of the invention will be discussed in greater detail with reference to the description of  FIGS. 14-16  below. The remaining two pin terminals may serve to provide two different detection signals to the UPS  10 . For example, the first signal may provide an indication whether the output module  18  is plugged into the UPS  10 . When the output module is unplugged from the UPS, the UPS power output shuts down, thereby assuring safety at the output contacts. Also, the UPS  10  output is not allowed to turn ON if the output module  16  is missing or not plugged in. The second signal may be provided to indicate one or three phase distribution. The presence of an output shorting jumper (as described below) indicates that the UPS  10  is configured for single phase output. 
   In a certain embodiment, the top wall  80  of the housing  72  of the output module  18  includes a circularly-shaped, perforated cutout  98  formed therein. The cutout  98  is provided to be selectively removed from the top wall  80  of the housing  72  to enable cables or wires to pass therethrough for connection to the terminals. 
   Turning now to  FIGS. 8-13 , the input module may be selectively configured to accommodate a variety of wiring schemes. In particular,  FIG. 8  illustrates a single feed, a single phase input and a single phase output configuration.  FIG. 9  illustrates a dual feed, a single phase input and a single phase output configuration.  FIG. 10  illustrates a single feed, a three phase input and a single phase output configuration.  FIG. 11  illustrates a dual feed, a three phase input and a single phase output configuration.  FIG. 12  illustrates a single feed, a three phase input and a three phase output configuration. And finally,  FIG. 13  illustrates a dual feed, a three phase input and a three phase output configuration. In a certain embodiment, in order to achieve any one of the desired configurations, a kit of jumper elements may be provided. Specifically, by installing jumper elements in the manner described below, a desired configuration may be achieved by a person installing the input module  16 . When a shorting jumper element is installed, the respective socket terminals  40  are connected in parallel and the total alternating current (“AC”) is distributed equally among these paralleled terminals. In another embodiment, the jumper elements may be replaced by a control, such as a rotary switch or relays, to provide the desired connections of the terminals. 
   Referring first to  FIG. 8 , to achieve a single power feed, a single phase input and a single phase output configuration, the input module  16  may be configured with a main shorting jumper element  100 , a bypass shorting jumper element  102 , and three secondary shorting jumper elements  104 ,  106  and  108 . In a certain embodiment, the jumper elements  100 ,  102 ,  104 ,  106  and  108  may be secured to their respective terminals L 1 , L 2 , L 3 , B 1 , B 2  and B 3  in the manner described below by screw fasteners (not shown). Single phase AC current provided by a main source may be connected by means of a wire, cable or other suitable flexible connector (referred to as a “wire” or “cable” herein) to screw lug  46  of terminal L 1 . This connection is represented by arrow  110  in  FIG. 8 . Arrows  112  represent the socket terminals  40   a ,  40   b ,  40   c ,  40   d ,  40   e  and  40   f , which are connected in parallel. The total AC current through the wire represented by arrow  110  is distributed among socket terminals L 1 , L 2 , L 3  or B 1 , B 2 , B 3  depending on the UPS  10  mode of operation. To complete the connection, the neutral wire is connected to screw lugs  48 ,  50  and the ground wire is connected to screw lugs  52 ,  54  or  56 ,  58 , which are provided on the neutral terminal N and ground terminal G, respectively. Arrows  113 ,  114  represent the connection of the wires to the respective neutral and ground terminals, respectively. Arrows  116 ,  118  represent the connection of the neutral and ground terminals to the UPS  10  via the socket terminal  40  (specifically  40   g  in  FIG. 5 ) and the pin terminal  42 . 
   To prevent the unwanted connection of the single phase main source wire to the other screw lugs  46  of the main source connections, i.e., terminals L 2  and L 3 , the main shorting jumper element  100  is configured with two blocking segments  120 ,  122 . As shown in  FIG. 3 , the blocking segments  120 ,  122  extend along a generally vertical plane from the main shorting jumper element. In one embodiment, the main shorting jumper element  100  and the blocking segments  120 ,  122  are fabricated from a piece of stamped metal material suitable to provide electrical communication between the terminals. The blocking segments  120 ,  122 , as with the blocking segments described below, are sized so as to prevent the physical connection of a wire to the terminals L 2  and L 3 . Similarly, to prevent the unwanted connection of the single phase main source wire to the screw lugs  46  of the bypass source connections, i.e., terminals B 1 , B 2  and B 3 , the bypass shorting jumper element  102  includes two blocking segments  124 ,  126 . In addition, the three secondary jumper elements each have a blocking segment to prevent the unwanted connection of the single phase main source wire to any of the bypass source connections. Specifically, the first secondary jumper element  104 , which provides electrical communication between terminals L 1  and B 1 , includes a blocking segment  128  to prevent access to terminal B 1 . The second secondary jumper element  106 , which provides electrical communication between terminals L 2  and B 2 , includes a blocking segment  130  to prevent access to terminal B 2 . And lastly, the third secondary jumper element  108 , which provides electrical communication between terminals L 3  and B 3 , includes a blocking segment  132  to prevent access to terminal B 3 . 
   Referring to  FIG. 9 , to achieve a dual feed, a single phase input and a single phase output configuration, the input module  16  may be configured with the main shorting jumper element  100  and the bypass shorting jumper element  102 . As shown, single phase AC current provided by a main source is connected by means of a wire to the screw lug of terminal L 1 . This connection is represented by arrow  134  in  FIG. 9 . Similarly, a single phase AC current by an alternate source is connected by a wire to the screw lug of terminal B 1 . This connection is represented by arrow  136 . As described above, the alternate source may be taken from a second power source, e.g., secondary AC power source, battery, generator, or any other suitable backup power source. Arrows  138  represent the socket terminals  40   d ,  40   e ,  40   f , which are connected in parallel. The total AC current provided by the main power source through the wire represented by arrow  134  is distributed among socket terminals L 1 , L 2 , L 3  to the UPS  10 . During bypass operation of the UPS  10 , arrows  140  represent the socket terminals  40   a ,  40   b ,  40   c , which are connected in parallel. The total AC current provided by the alternate power source through the wire represented by arrow  136  distributed among socket terminals B 1 , B 2 , B 3  to the UPS  10 . To complete the connection, the neutral and ground wires are connected to screw lugs  48 ,  50 ,  52 ,  54 ,  56  and  58  provided on the neutral terminal N and the ground terminal G, respectively. Arrows  142 ,  144  represent the connection of the wires to the respective neutral and ground terminals. Arrows  146 ,  148  represent the connection of the neutral and ground terminals to the UPS  10  via the socket terminal  40   g  and the pin terminal  42 . 
   To prevent the unwanted connection of the single phase main source wire to the other screw lugs  46  of the main source connections, i.e., terminals L 2  and L 3 , the main shorting jumper element  100  is configured with two blocking segments  120 ,  122  positioned in front of these terminals. Similarly, to prevent the unwanted connection of the single phase alternate source wire to the screw lugs of the bypass source connections, i.e., terminals B 2  and B 3 , the bypass shorting jumper element  102  includes two blocking segments  124 ,  126  positioned in front of these terminals. 
   Referring to  FIG. 10 , to achieve a single feed, a three phase input and a single phase output configuration, the input module  16  may be configured with the bypass shorting jumper element  102  and the first secondary jumper element  104 . As shown, three phase AC current provided by a main source is connected by means of three wires to the screw lugs of terminals L 1 , L 2  and L 3 . This connection is represented by arrows  150 ,  152  and  154  in FIG.  10 . Arrows  156 ,  158  and  160  represent the connection of the socket terminals corresponding terminals L 1 , L 2  and L 3  to the UPS  10  (specifically, socket terminals  40   d ,  40   e  and  40   f  as shown in  FIG. 5 ) and during bypass operation of UPS  10 , arrows  156  represent the socket terminals  40 ,  40   b ,  40   c , which are connected in parallel. The total AC current through the wire represented by arrow  152  is distributed among socket terminals B 1 , B 2 , B 3 . To complete the connection, the neutral and ground wires are connected to the screw lugs provided on the neutral terminal N and ground terminal G, respectively. Arrows  162 ,  164  represent the connection of the wires to the respective neutral and ground terminals. Arrows  166 ,  168  represent the connection of the neutral and ground terminals to the UPS  10  via the socket terminal  40   g  and the pin terminal  42 . 
   To prevent the unwanted connection of the three phase main source wires to the screw lugs of the alternate power source connections, i.e., terminals B 1 , B 2  and B 3 , the bypass shorting jumper element  102  is configured with two blocking segments  124 ,  126  positioned in front of two of the bypass terminals, e.g., terminals B 2  and B 3 , and the first secondary jumper element  104  is configured with a single blocking segment  128  positioned in front of the remaining bypass terminal, e.g., terminal B 1 . 
   Referring to  FIG. 11 , to achieve a dual feed, a three phase input and a single phase output configuration, the input module  16  may be configured with the bypass shorting jumper element  102  only. As shown, three phase AC current provided by a main source is connected by means of three wires to the screw lugs of terminals L 1 , L 2  and L 3 . This connection is represented by arrows  170 ,  172  and  174  in  FIG. 11 . Similarly, a single phase AC current by an alternate source is connected by a wire to the screw lug of terminal B 1 . Arrow  176  represents this connection to terminal B 1 . Arrows  178 ,  180 ,  182  represent the connection of socket terminals corresponding to terminals L 1 , L 2 , L 3  to the UPS (specifically, socket terminals  40   d ,  40   e ,  40   f , respectively, as shown in  FIG. 5 ). Arrow  184  represent the socket terminals  40   a ,  40   b ,  40   c , which are connected in parallel. The total AC current through the wire represented by arrow  176  is distributed among socket terminals B 1 , B 2 , B 3 . To complete the connection, the neutral and ground wires are connected to the screw lugs provided on the neutral terminal N and ground terminal G, respectively. Arrows  186 ,  188  represent the connection of the wires to the respective neutral and ground terminals. Arrows  190 ,  192  represent the connection of the neutral and ground terminals to the UPS via the socket terminal  40   g  and the pin terminal  42 . 
   To prevent the unwanted connection of the single phase alternate source wire to the other screw lugs of the alternate source connections, i.e., terminals B 2  and B 3 , the bypass shorting jumper element  102  is configured with two blocking segments  124 ,  126  positioned in front of these terminals. 
   Referring to  FIG. 12 , to achieve a single feed, a three phase input and a three phase output configuration, the input module  16  may be configured with the first secondary jumper element  104 , the second secondary jumper element  106  and the third secondary jumper element  108 . As shown, three phase AC current provided by a main power source is connected by means of three wires to the screw lugs of terminals L 1 , L 2  and L 3 . This connection is represented by arrows  194 ,  196  and  198  in  FIG. 12 . Arrows  200 ,  202  and  204  represent the current through the socket terminals corresponding to terminals L 1 , L 2 , L 3  (specifically, socket terminals  40   d ,  40   e ,  40   f , respectively, as shown in  FIG. 5 ) to the UPS  10  or through the socket terminals corresponding to terminals B 1 , B 2 , B 3  (specifically, socket terminals  40   a ,  40   b ,  40   c , as shown in  FIG. 5 ) depending on the UPS  10  mode of operation. To complete the connection, the neutral and ground wires are connected to the screw lugs provided on the neutral terminal N and ground terminal G, respectively. Arrows  206 ,  208  represent the connection of the wires to the respective neutral and ground terminals. Arrows  210 ,  212  represent the connection of the neutral and ground terminals to the UPS  10  via the socket terminal  40   g  and the pin terminal  42 . 
   To prevent the unwanted connection of the three phase main power source wires to the screw lugs of the alternate source connections, i.e., terminals B 1 , B 2  and B 3 , the first, second and third secondary jumper elements  104 ,  106 ,  108  are configured with blocking segments  128 ,  130 ,  132 , respectively, which are positioned in front of these terminals. As shown, the first, second and third secondary jumper elements  104 ,  106 ,  108  may direct power from the main AC source to the main UPS circuit and to the bypass UPS circuit. 
   Referring to  FIG. 13 , to achieve a dual feed, a three phase input and a three phase output configuration, the input module may be configured without any of the aforementioned jumper elements, i.e., jumper elements  100 ,  102 ,  104 ,  106  and  108 . As shown, three phase AC current provided by a main power source is connected by means of three wires to the screw lugs of terminals L 1 , L 2  and L 3 . This connection is represented by arrows  214 ,  216  and  218  in  FIG. 13 . Similarly, three phase AC current provided by a bypass source is connected by means of three wires to the screw lugs of terminals B 1 , B 2  and B 3 . Arrows  220 ,  222  and  224  represent this connection. Arrows  226 ,  228 ,  230 ,  232 ,  234  and  236  represent the connection of the socket terminals corresponding to terminals L 1 , L 2 , L 3 , B 1 , B 2  and B 3  to the UPS  10  (specifically, socket terminals  40   d ,  40   e ,  40   f ,  40   a ,  40   b  and  40   c , respectively, as shown in  FIG. 5 ). To complete the connection, the neutral and ground wires are connected to the screw lugs provided on the neutral terminal N and ground terminal G, respectively. Arrows  238 ,  240  represent the connection of the wires to the respective neutral and ground terminals. Arrows  242 ,  244  represent the connection of the neutral and ground terminals to the UPS  10  via the socket terminal  40   g  and the pin terminal  42 . 
   Turning to  FIGS. 14-16 , and more particularly to  FIG. 14 , to achieve a single phase output connection, the output module  18  may be configured with an output shorting jumper element  246 . In a certain embodiment, the output shorting jumper element  246  may be secured to terminals L 1 , L 2 , L 3  and N by screw fasteners. As shown, single phase current is provided from the UPS  10  by means of pin terminals on L 1 , L 2  and L 3 , which are provided in the formation  88  projecting from the front wall  74  of the housing, and the output shorting jumper element  246 . The formation  88  is pluggable into the socket  90  provided in the UPS  10  (see  FIG. 1 ). This connection is represented by arrows  248  in  FIG. 14 . Arrow  250  represents the connection of the terminal corresponding to terminal L 3  to a desired hardwired output. It should be understood that the connection could be made either of the other two terminals L 1  and L 2 . To complete the connection, the neutral and ground wires are connected to screw lugs  96  provided on the neutral terminal N and ground terminal G, respectively. Arrows  254 ,  252  represent the connection of the wires to the respective neutral and ground terminals to the output. As described above, the wires represented by arrows  250 ,  252 ,  254  may be connected to any device requiring conditioned power. For example, the device may include but is not limited to computers, servers, auxiliary devices, etc. 
   The UPS  10  may be configured to communicate with sensors that measure voltages across all of the terminals L 1 , L 2 , L 3 , B 1 , B 2  and B 3 . The information obtained from the sensors may be processed for determining as to the type of AC power source connected to the UPS, and for warning an operator of an improper configuration. 
   Referring to  FIG. 15 , to achieve a three phase output connection, three phase current is provided from the UPS  10  by means of three pin terminals L 1 , L 2  and L 3  of the output module  18 . This connection is represented by arrows  256 ,  258 ,  260  in  FIG. 15 . Arrows  262 ,  264  and  266  represent the connection of the terminals corresponding to terminals L 1 , L 2  and L 3 , respectively to a desired hardwired output. To complete the connection, the neutral and neutral wires are connected to screw lugs  96  provided on the neutral terminal N and ground terminal G, respectively. Arrows  268 ,  270  represent the connection of the wires to the respective neutral and ground terminals to the output. 
   Referring now to  FIG. 16 , to achieve a single phase output connection to a battery pack power distribution unit (“PDU”)  272 , the output module  18  may be configured with the output shorting jumper element  246 . As shown, single phase current is provided from the UPS  10  by means of a PDU connector to screw lug  96  of terminal L 1 . This connection is represented by arrow  276  in  FIG. 16 . Arrow  278  represents the connection of the terminal corresponding to terminal L 1  to the desired hardwired output. As with the configuration illustrated in  FIG. 14 , to complete the connection, a neutral connector  280  and a ground connector  282  associated with the battery pack  272  are connected to screw lugs  96  provided on the neutral terminal N and ground terminal G, respectively. Arrows  284 ,  286  represent the connection of the connectors  280 ,  282  to the neutral and ground terminals, respectively. Arrows  288 ,  290  represent the connection of the wires to the respective neutral and ground terminals to the desired hardwired output. 
   As further illustrated in  FIGS. 14-16 , the output module  18  may be provided with a strain relief bar  292  to secure the assist in preventing the unwanted or unintentional removal of the wires connected to the terminals. 
   The output module  18 , when provided with the output jumper element  246 , provides single phase AC output. When the output jumper element  246  is removed, the output module  18  may be wired to provide three phase AC power to the desired hardwired output. The UPS  10  may be configured to communicate with sensors that measure voltages across all of the terminals L 1 , L 2  and L 3  and/or the output jumper element  246  of the output module  18 . The information obtained from the sensors may be processed for determining an improper power configuration, and for warning an operator of the improper configuration. 
     FIG. 17  illustrates the operation of the input module  16  and the output module  18  within the UPS  10 .  FIG. 17  illustrates schematically the input module  16 , the output module  18 , a converter  300  of the UPS  10 , a battery  302 , and a controller  304 , which controls the operation of the UPS. As discussed above, during normal operation, the UPS converter  300  is designed to covert utility power to conditioned power for a connected load  306 . 
   As shown, power travels from a primary power source into and from the input module  16 , to the UPS converter  300 , and to the output module  18  along line  308 . During a power disturbance or interruption, for example, the UPS  10  may be configured to provide power to the connected load  306  via the output module  18  from the battery  302  (or batteries) for a finite period of time. Specifically, the UPS  10  transfers to battery operation if the supply of utility power fails or is outside predefined limits. As shown, the battery  302  provides power directly to the converter  300  along line  310  and to the output module  18 . 
   Power travels from the primary (or an alternate) power source into and from the input module  16 , around the UPS converter  300 , and to the output module  18  along line  312 . During bypass operation, bypass mode is reached either as a user selection or automatically under the control of the controller by employing a switch  314 . For example, the UPS  10  may be configured with a display (not shown) that provides a menu screen to manually select the bypass mode. Alternatively, the controller  304  may be configured to automatically switch to bypass mode if, for example, the following conditions occur: both normal and battery operation modes are unavailable; an output overload condition occurs, or if the UPS incurs an internal fault or trigger. As shown, during bypass operation, the utility power is connected to the load  306 , bypassing the converter  300 . If bypass mode becomes unavailable, the UPS will automatically switch to main power. In the event the main power is unavailable, the controller  304  will switch to battery power. 
   In one embodiment, a rotary switch may be provided in place of the main, bypass and supplemental jumpers. In another embodiment, the input module and the output module may be configured to provide split phase power. In yet another embodiment, the voltages of the terminals L 1 , L 2 , L 3 , B 1 , B 2 , B 3  of the input module may be sensed and processed by the controller for determining the type of AC source connected and for determining and providing a warning to the operator of any improper configuration. 
   Thus, it should be observed that the UPS of embodiments of the invention may enable a system operator to have one UPS for different input and output power configurations, which ultimately reduces cost of ownership of the system, simplifies and reduces cost of manufacturing, service, repair and installation. In addition, the UPS of embodiments of the invention may be configured to accept AC power input from up to two separate sources. In a first instance, the first source may be configured to either feed both the main UPS circuit and the bypass UPS circuit in the case of a single feed application. In a second instance, the first source feeds the main UPS circuit and the second source feeds the bypass UPS circuit in the case of a dual feed application. Each of these input sources may be configured as one phase or three phases independently from each other. 
   Also, the UPS of embodiments of the invention may be configured to have AC input and output jumpers, and with respect to the input module, the input jumpers may be further configured to prevent the miswiring of the input output module. Based on all six input voltage measurements and output phase configuration jumper, a determination may be made of improper power configuration. 
   Having thus described at least one illustrative embodiment of the invention, various alterations, modifications and improvements will readily occur to those skilled in the art. Such alterations, modifications and improvements are intended to be within the scope and spirit of the invention. Accordingly, the foregoing description is by way of example only and is not intended as limiting. The invention&#39;s limit is defined only in the following claims and the equivalents thereto.