Abstract:
A functional module comprises a front cover having a front side defining an electrical distribution function and a back cover having a back side defining a plurality of shielded plugs. A contact set is adapted to communicate electrical power via the shielded plugs for the electrical distribution function. The front cover and said back cover are configured to latch together so as to enclose at least a portion of the contact set.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a divisional of U.S. patent application Ser. No. 10/443,444 entitled Safety Module Electrical Distribution System, filed May 22, 2003, which relates to and claims the benefit of prior U.S. Provisional Applications No. 60/383,269 entitled Safety Plug-In Module Electrical Distribution System, filed May 23, 2002 and No. 60/441,852 entitled Safety Module Electrical Distribution System, filed Jan. 21, 2003. This application also relates to and claims the benefit of prior U.S. Provisional Application No. 60/649,318 entitled Dimmer Switch Module, filed Feb. 1, 2005. All of the aforementioned prior applications incorporated by reference herein. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     Standard AC electrical systems are comprised of an electrical box and an electrical device, such as an outlet or switch, installed within the box. During a roughing phase of construction, electrical boxes are mounted to wall studs at predetermined locations. After the boxes are installed, a journeyman electrician routes power cables through building framing to the appropriate boxes. The power cable is fed through openings in the rear or sides of the electrical boxes and folded back into the boxes, unterminated, so as to be out of the way until the next phase. During a makeup phase, wall panels are installed and painted, and the journeyman returns to the construction site to install the electrical devices into the boxes. After conductors are wired to an electrical device, it and the attached conductors are pushed into the electrical box and the device is attached to the top and bottom of the box with screws. During a trim phase, face plates are mounted over the open-end of the electrical boxes, completing the standard electrical wiring process.  
       SUMMARY OF THE INVENTION  
       [0003]     Standard AC electrical systems are problematic in construction and use, with respect to costs, safety and functionality. From an electrical contractor perspective, a journeyman electrician must make two separate trips to the job site, one for the rough phase and one for the makeup phase. Also, during the makeup phase, installation of the wall panels can damage the work completed during the rough phase. This occurs, for example, when a router contacts exposed cables as drywallers create a hole to accommodate electrical box openings. Another form of damage occurs when drywall compound or paint fouls the exposed cables, insulation and labeling.  
         [0004]     From a general contractor&#39;s perspective, verification of the electrical contractor&#39;s work is not possible until after the makeup phase. Until then, the electrical cables are unterminated. After the makeup phase, however, miswiring typically requires cutouts in the installed wall panels and associated patches after corrections are completed. Further, the electrical system cannot be activated until after verification. Thus, during the rough and makeup phases, electricity for tools and lighting must be supplied by generators, which create hazards due to fumes, fuel, and noise and are an unreliable electrical source. In addition, until the trim phase is completed, unskilled personnel have access to the electrical cable. Tampering can compromise the integrity of the electrical wiring and also create a safety problem after power is activated.  
         [0005]     From a homeowner&#39;s perspective, there are problems with repair of the standard electrical wiring. Replacement of a broken outlet or switch device first requires removal of a face plate. The screws that attach the module to the top and bottom of the electrical box must be removed next. The device is then removed from the box and the conductors are removed by loosing the screws on the outlet sides. The process is then reversed to attach the conductors to a new device and mount the new device into the electrical box.  
         [0006]     The prior art electrical device replacement procedure described above exposes the homeowner to AC wiring upon removal of the face plate. This exposure creates a shock hazard. Further, a homeowner&#39;s reluctance to change out broken devices or to spend the money to hire an electrician also creates a shock and a fire hazard from continued use of cracked, broken or excessively worn outlets or switches. In addition, the integrity of the original wiring becomes questionable if a homeowner or other third party removes and replaces an electrical device. Miswiring by a third party can violate building codes and create shock and fire hazards, such as inadvertently switching the hot and neutral conductors, failing to attach ground wires, kinking or nicking conductors or improperly tightening connections.  
         [0007]     A modular electrical distribution system benefits the electrical contractor in several respects. A wiring module is installed internally to an electrical box and associated functional modules, such as a dimmer switch module, are removably installed into the wiring module without exposure to or access to electrical system wiring attached behind the panel. The journeyman&#39;s work can completed at the rough phase, when installation of the wiring module is complete. Thus, there is no need for the journeyman to return to the job site during the makeup phase because any semi-skilled laborer can insert, for example, an appropriate outlet or switch module. Further, there is no wiring access after the rough phase, protecting wiring integrity. Also, there are no exposed conductors or parts inside the electrical box that can be inadvertently damaged during wall panel installation.  
         [0008]     A modular electrical distribution system also benefits the general contractor. Because wiring is completed during rough framing, verification and activation of the building electrical system can be performed at the rough phase. Miswiring can be corrected before wall panels are installed and painted, eliminating cut and patch repairs. Early electrical system activation eliminates the need to use generators. Lack of third party access to the journeyman&#39;s wiring preserves integrity after verification and eliminates shock exposure to other workers.  
         [0009]     A modular electrical distribution system also benefits the homeowner. Replacement of broken sockets and switches can be easily and safely accomplished. Safety is enhanced by reducing exposure to electrical wiring and encouraging replacement of defective outlets and switches. Further, maintenance costs are reduced by reducing the need to hire an electrician for repairs. Wiring integrity is insured by reducing the opportunity of unqualified third parties to access the electrical system. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     FIGS.  1 A-B are perspective views of an outlet module installed and removed, respectively, from a corresponding wiring module;  
         [0011]     FIGS.  2 A-B are perspective views of a switch module installed and removed, respectively, from a corresponding wiring module;  
         [0012]      FIGS. 3-8  are perspective views of an outlet module and outlet module components;  
         [0013]     FIGS.  3 A-B are front and back perspective views, respectively, of an outlet module;  
         [0014]     FIGS.  4 A-B are exploded, front perspective views of outlet modules;  
         [0015]     FIGS.  5 A-B are front and back perspective views, respectively, of an outlet module front cover;  
         [0016]     FIGS.  6 A-B are front and back perspective views, respectively, of an outlet module back cover;  
         [0017]     FIGS.  7 A-B are front and back perspective views, respectively, of an outlet module power contact set;  
         [0018]     FIGS.  8 A-B are front and back perspective views, respectively, of an outlet module ground contact set;  
         [0019]      FIGS. 9-15  are perspective views of a switch module and switch module components;  
         [0020]     FIGS.  9 A-B are front and back perspective views, respectively, of a switch module;  
         [0021]      FIG. 10  is an exploded, front perspective view of a switch module;  
         [0022]     FIGS.  11 A-B are front and back perspective views, respectively, of a switch module switch;  
         [0023]     FIGS.  12 A-B are front and back perspective views, respectively, of a switch module front cover;  
         [0024]     FIGS.  13 A-B are front and back perspective views, respectively, of a switch module single-pole, single throw (SPST) contact set;  
         [0025]     FIGS.  13 C-D are front and back perspective views, respectively, of a switch module single-pole, double throw (SPDT) contact set;  
         [0026]     FIGS.  13 E-F are front and back perspective views, respectively, of a switch module double-pole, double throw (DPDT) contact set;  
         [0027]     FIGS.  14 A-B are front and back perspective views, respectively, of a switch module actuator;  
         [0028]     FIGS.  15 A-B are front and back perspective views, respectively, of a switch module back cover;  
         [0029]      FIGS. 16-22  are perspective views of a wiring module and wiring module components;  
         [0030]     FIGS.  16 A-B are front and back perspective views, respectively, of a terminal-block wiring module;  
         [0031]     FIGS.  16 C-D are back perspective views of a terminal-block wiring module and associated terminal guards in open positions;  
         [0032]     FIGS.  16 E-F are front and back views, respectively, of a terminal-block wiring module and position-dependent wiring labels;  
         [0033]     FIGS.  16 G-H are switch and outlet wiring schematics, respectively;  
         [0034]      FIG. 17A -B are exploded, front perspective views of a terminal-block wiring module with stationary-mount and swivel-mount terminal guards, respectively;  
         [0035]     FIGS.  18 A-B are front and back perspective views and a back view, respectively, of a wiring panel;  
         [0036]     FIGS.  19 A-B are front and back perspective views, respectively, of a mounting bracket;  
         [0037]     FIGS.  20 A-B are front and back perspective views, respectively, of a wiring panel front cover;  
         [0038]     FIGS.  21  is a perspective view of a wiring panel terminal set;  
         [0039]     FIGS.  22 A-B are front and back perspective views, respectively, of a wiring panel back cover;  
         [0040]     FIGS.  23 A-B are front and back perspective views, respectively, of a fixed-wire wiring module;  
         [0041]     FIGS.  24 A-B are exploded, front and back perspective views, respectively, of a fixed-wire wiring module;  
         [0042]     FIGS.  25 A-B are front and back perspective views, respectively, of an electrical box cover;  
         [0043]     FIGS.  26 A-B are front perspective views of a covered and uncovered electrical box, respectively;  
         [0044]      FIG. 27  is a front perspective view of a 2-gang electrical box with overlapping covers;  
         [0045]     FIGS.  28 A-B are back perspective and back perspective exploded views, respectively, of a wiring module having a terminal shield;  
         [0046]     FIGS.  29 A-B are front and back perspective views, respectively, of a terminal shield;  
         [0047]     FIGS.  30 A-B are front and back perspective views, respectively, of a dimmer switch module;  
         [0048]      FIG. 31  is an exploded, front perspective view of a dimmer switch module;  
         [0049]     FIGS.  32 A-B are front and back perspective views, respectively, of a power control;  
         [0050]     FIGS.  33 A-B are front and back perspective views, respectively, of a front cover;  
         [0051]     FIGS.  34 A-B are front and back perspective views, respectively, of a spring;  
         [0052]     FIGS.  35 A-B are front and back perspective views, respectively, of a dimmer control;  
         [0053]     FIGS.  36 A-B are front and back perspective views, respectively, of a heat sink;  
         [0054]     FIGS.  37 A-C are front perspective, back perspective and front views, respectively, of dimmer circuit board;  
         [0055]     FIGS.  38 A-B are front and back perspective views, respectively, of a back cover; and  
         [0056]      FIG. 39  is a schematic diagram of a dimmer circuit. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0000]     System Overview  
         [0057]      FIGS. 1-2  illustrate a safety module electrical distribution system  100  having a functional module  110  and a wiring module  1600 . The electrical distribution system  100  is configured to mount within a standard electrical box (not shown), such as is typically installed within a building wall. In particular, the wiring module  1600  is configured to be easily installed within an electrical box, and a functional module  110  is configured to be removably plugged into the wiring module  1600 , as described below. FIGS.  1 A-B show an outlet module  300  in an installed and a removed position, respectively. FIGS.  2 A-B show a switch module  900  in an installed and a removed position, respectively. A face plate (not shown) may be installed over a functional module  110  so as to provide an aesthetic trim.  
         [0058]     As shown in  FIGS. 1-2 , each functional module  110  provides a user-accessible electrical distribution function. As shown in FIGS.  1 A-B, the functional module  110  may be an outlet module  300 , which functions to supply a user with electrical power through a conventional AC plug inserted into one of the module sockets. The outlet module  300  is configured for installation in a ground-up position in a wiring module  1600  oriented for outlet installation. Alternatively, an outlet module and wiring module can be configured for outlet installation in a ground-down position.  
         [0059]     As shown in FIGS.  2 A-B, the functional module  110  may be a switch module  900 , which allows a user to control electrical power to an outlet, a light or any of various electrical devices (not shown) by actuating the module switch. The switch is slideable between first and second positions in contrast to a conventional toggle switch, such as used for turning an interior light on and off. The switch module  900  is configured for installation in a wiring module  1600  oriented for switch installation. Reversible wiring module  1600  orientation within an electrical box to indicate the module to be installed and its proper orientation is described in detail with respect to FIGS.  16 A-H, below  
         [0060]     Other outlet and switch related functional modules  110  may include GFCI outlets, covered safety outlets and dimmer switches ( FIGS. 23-24 ) to name just a few. Further, the electrical distribution system  100  may be wall-mounted, ceiling-mounted or floor-mounted. In additional, the electrical distribution system  100  can be adapted for uses other than building electrical distribution, such as airplane, automobile or boat electrical distribution applications, to name a few. A modular electrical outlet and switch system is described in U.S. Pat. No. 6,341,981 entitled Safety Electrical Outlet and Switch System, and a covered safety outlet module and corresponding plug are described in U.S. patent application Ser. No. No. 10/737,713 entitled Safety Plug and Covered Outlet Module, both assigned to ProtectConnect, Irvine, Calif. and incorporated by reference herein.  
         [0000]     Outlet Module  
         [0061]     FIGS.  3 A-B illustrate an outlet module  300  having a body  310 , a front side  301  and a back side  302 . The body  310  accepts attachment screws  305  on diagonally opposite corners that are utilized to secure the outlet module  300  to a wiring module  1600  (FIGS.  1 A-B). The outlet module front side  301  provides upper and lower sockets  320  each configured to accept a conventional, three-wire (grounded) electrical plug. The outlet module back side  302  provides shielded plugs  330  and a ground bar  834  that physically and electrically connect the outlet module  300  to a wiring module  1600  (FIGS.  1 A-B). The shielded plugs  330  transfer electrical power to the sockets  320 , and the ground bar  834  provides a ground path for the sockets  320 . The ground bar  834  also functions as a key to assist in orienting the outlet module  300  relative to the wiring module  1600  (FIGS.  1 A-B).  
         [0062]      FIG. 4A  illustrates an outlet module  300  having a front cover  500 , a rear cover  600 , a power contact set  700  and a ground contact set  800 . The front cover  500  and back cover  600  form the outlet module body  310  (FIGS.  3 A-B). The covers  500 ,  600  advantageously snap together with a latch and catch assembly, described with respect to  FIGS. 5-6 , below. This reduces manufacturing assembly steps and reduces or eliminates the need for separate fasteners, such as rivets or screws and/or sonic welding. The contact set  700 ,  800  is retained within the covers  500 ,  600  and provides conductive paths from the wiring panel  1600  (FIGS.  16 A-B) to the outlet sockets  320  ( FIG. 3A ). In particular, a power contact set  700  transfers power from the shielded plugs  330  ( FIG. 3B ) to the outlet sockets  320  ( FIG. 3A ). A ground contact set  800  provides a ground path between a ground bar  834  ( FIG. 3B ) and the outlet sockets  320  ( FIG. 3A ). The ground contact set components  810 ,  830 ,  850  are assembled as described with respect to FIGS.  8 A-B, below. In one embodiment, the covers  500 ,  600  are constructed of nylon.  FIG. 4B  illustrates an alternative embodiment of an outlet module  400 , such as for  20 A applications  
         [0063]     FIGS.  5 A-B illustrate the outlet module front cover  500  having an outside face  501 , an inside face  502 , outlet apertures  510 , attachment ears  520 , side latches  530  and contact housing structure  540 ,  550 . As shown in  FIG. 5A  on the outside face  501 , the outlet apertures  510  form the entry to the outlet module sockets  320  ( FIG. 3A ) and include a hot slot, neutral slot and ground hole for each of a top socket and bottom socket. The attachment ears  520  are advantageously integral to the front cover  500 , eliminating the need for a separate mechanism for attaching the outlet module  300  (FIGS.  3 A-B) to the wiring module  1600  (FIGS.  16 A-B). The attachment ears  520  are located at an upper right corner and a diagonally opposite lower left corner (not visible), and each has a fastening aperture that accepts, for example, an attachment screw  305  (FIGS.  3 A-B). The side latches  530  form the front cover portion of the latch and catch assembly, functionally described with respect to  FIG. 4 , above.  
         [0064]     As shown in  FIG. 5B  on the inside face  502 , a power contact structure  540  accepts the power contact set  700  (FIGS.  7 A-B) so that the power contact clips  701  (FIGS.  7 A-B) align with the hot and neutral slots of the outlet apertures  510 . A ground contact structure  550  accepts the ground contact set  800  (FIGS.  8 A-B) so that the ground contact clips  832 ,  852  (FIGS.  8 A-B) align with the ground holes of the outlet apertures  510 .  
         [0065]     FIGS.  6 A-B illustrate the outlet module back cover  600  having an outside face  601 , an inside face  602 , plug shields  610 , a ground bar aperture  620 , side catches  630  and contact support structure  640 ,  650 . As shown in  FIG. 6B  on the outside face  601 , the plug shields  610  advantageously provide the shield portion of the shielded plugs  330  ( FIG. 3B ). Specifically, the plug shields  610  completely surround all sides of the power contact set prongs  702  (FIGS.  7 A-B). In this manner, the prongs  702  (FIGS.  7 A-B) are not exposed when the outlet module plugs  330  ( FIG. 3B ) are engaged with the wiring module sockets  810  ( FIG. 18A ), even when the outlet module  300  (FIGS.  3 A-B) is partially separated from the wiring module  1600  (FIGS.  16 A-B). The ground bar aperture  620  allows the ground bar  834  (FIGS.  8 A-B) to protrude through the back cover  600 , providing a ground contact with the wiring module  1600  (FIGS.  16 A-B). The side catches  630  provide apertures that accept and engage the side latches  530  (FIGS.  5 A-B) so as to releaseably secure together the front cover  500  (FIGS.  5 A-B) and the back cover  600 .  
         [0066]     As shown in  FIG. 6A  on the inside face  602 , a power contact support structure  640  consists of slots that allow the prongs  702  (FIGS.  7 A-B) to protrude through the back cover  600  within the plug shields  610 , providing a power connection with the wiring module  1600  (FIGS.  16 A-B). A ground contact support structure  650  supports the ground contact set  800  (FIGS.  8 A-B).  
         [0067]     FIGS.  7 A-B illustrate the power contact set  700  having an upper hot contact  710 , a lower hot contact  720 , an upper neutral contact  730  and a lower neutral contact  740 . Each contact  710 - 740  has a prong clip  701  interconnected with a prong  702 . The prong clips  701  align with the front cover hot and neutral slots  510  ( FIG. 5A ) to form the outlet module sockets  320  ( FIG. 3A ). The prongs  702  insert through the power contact support structure  640  into the plug shields  610  to form the outlet module shielded plugs  330  ( FIG. 3B ). Advantageously, the power contact set  700  is configured so that the contacts may be manufactured by a stamp and fold process. In one embodiment, the contacts are brass.  
         [0068]     FIGS.  8 A-B illustrate a ground contact set  800  having a ground buss  810 , an upper ground contact  830  and a lower ground contact  850 . The ground clips  832 ,  852  align with the front cover ground holes  510  ( FIG. 5A ) to form the ground portion of the outlet module sockets  320  ( FIG. 3A ). The ground bar  834  protrudes through the back cover  600  (FIGS.  6 A-B) to provide a ground path connection with the wiring module  1600  (FIGS.  16 A-B). The unassembled ground contact set  800  is illustrated in  FIG. 4 , above. Ground contact set  800  assembly is described below.  
         [0069]     As shown in FIGS.  8 A-B, the ground buss  810  has a upper rivet  812 , a lower rivet  814 , a upper cutout  815 , a slot  816  and a lower cutout  818 . The ground buss  810  mechanically supports and electrically interconnects the upper ground contact  830  and the lower ground contact  850 . The upper ground contact  830  has an upper ground clip  832 , a ground bar  834 , leaves  836  and a tab  838 . The upper ground clip  832  and ground bar  834  extend from opposite ends of the upper ground contact  830 . The upper ground clip  832  accepts a ground pin from a standard AC electrical plug. The ground bar  834  inserts into a corresponding ground clip  1902  (FIGS.  19 A-B) in the wiring module  1600  (FIGS.  16 A-B). The tab  838  extends generally perpendicularly below and between the clip  832  and bar  834  and has an aperture corresponding to the top rivet  812 . The leaves  836  extend from the back of the clip  832 . The lower ground contact  850  has a lower ground clip  852 , leaves  854  and a tab  858 . The tab  858  extends generally perpendicularly to the clip  852  and has an aperture corresponding to the lower rivet  814 . The leaves  854  extend from the back of the clip  852 .  
         [0070]     Also shown in FIGS.  8 A-B, the ground contact set  800  is assembled by inserting the upper ground contact  830  and lower ground contact  850  into the ground buss  810 . Specifically, the ground bar  834  is inserted into the slot  816 , the leaves  836 ,  854  are inserted into the upper and lower cutouts  815 ,  818 , respectively, the upper and lower rivets  812 ,  814  are inserted through the tabs  838 ,  858 . The rivets  812 ,  814  are then splayed, fixedly attaching the upper and lower ground contacts  830 ,  850  to the ground buss  810 . Advantageously, the ground contact set  800  is configured so that the ground contact set components  810 ,  830 ,  850  may be manufactured by a stamp and fold process. In one embodiment, the upper and lower ground contacts  830 ,  850  are brass and the ground buss  810  is zinc-plated steel.  
         [0000]     Switch Module  
         [0071]     FIGS.  9 A-B illustrate a switch module  900  having a body  910 , a front side  901  and a back side  902 . Like the outlet module body  310  (FIGS.  3 A-B), the switch module body  910  accepts screws on diagonally opposite corners that are utilized to secure the switch module  900  to a wiring module  1600  (FIGS.  2 A-B). The switch module front side  901  has a slideable switch  1100  configured to actuate internal contacts so as to route electrical power, to turn on and off a light, for example. Like the outlet module  300  (FIGS.  3 A-B), the switch module back side  902  provides shielded plugs  930  that physically and electrically connect the switch module  900  to a wiring module  1600  (FIGS.  2 A-B). The shielded plugs  930  conduct electrical power under control of the switch  1100 . There may be null plugs  940  having no conductors depending on the switch module  900  configuration and associated function, as described with respect to FIGS.  13 A-F, below. The switch module  900  does not require a ground path to the wiring module  1600  (FIGS.  2 A-B). A key bar  1520 , therefore, provides a non-conducting structure that substitutes for a ground bar  834  ( FIG. 3B ), to assist in orienting the switch module  900  relative to the wiring module  1600  (FIGS.  2 A-B).  
         [0072]      FIG. 10  illustrates a switch module  900  having a switch  1100 , a front cover  1200 , a rear cover  1500 , a contact set  1300 , an actuator  1400  and a spring  1000 . The front cover  1200  and back cover  1500  form the switch module body  910  (FIGS.  9 A-B). The covers  1200 ,  1500  advantageously snap together and are secured with a latch and catch assembly, described with respect to FIGS.  12 A-B and  15 A-B, below. This reduces manufacturing assembly steps and reduces or eliminates the need for separate fasteners, such as rivets or screws and/or sonic welding. In one embodiment, the covers  1200 ,  1500  are constructed of nylon.  
         [0073]     As shown in  FIG. 10 , the switch  1100  snaps into and is slidably retained by the front cover  1200  and engages the actuator  1400 . The switch  1100  is movable between a first position and a second position. The contact set  1300 , actuator  1400  and spring  1000  are retained within the covers  1200 ,  1500 . The contact set  1300  routes electrical power from the wiring panel  1600  (FIGS.  1 A-B) as determined by the switch  1100  positions. In particular, the position of the switch  1100  determines the position of the actuator  1400 , which, in turn, determines whether the contact set  1300  is open or closed. If closed, the contact set  1300  provides a conductive path that transfers power between the shielded plugs  930  ( FIG. 3B ). The switch  1100  remains in its manually set position under tension from the spring  1000 .  
         [0074]     FIGS.  11 A-B illustrate a switch  1100  that is generally rectangular, having a front side  1101  and a back side  1102 . The front side  1101  has a finger grip  1110  for manually sliding the switch between its first position and its second position, as described above. The back side  1102  has latches  1120  and a lever  1130  that extends in a direction generally normal to the plane of the back side  1102 . The latches  1120  are configured to pass through front cover slots  1214  ( FIG. 12A ), which cause the latches  1120  to flex inward toward the extension  1130  as the switch  1100  is pressed into the front cover  1200  (FIGS.  12 A-B). The latches  1120  spring outward after the latches pass through the slots  1214  ( FIG. 12A ), seating the switch in the front cover  1200  (FIGS.  12 A-B), as described below. The lever tip  1132  inserts through the actuator slot  1410  (FIGS.  14 A-B) and contacts the spring  1000 , mechanically connecting the switch  1100  to the actuator  1400  (FIGS.  14 A-B).  
         [0075]     FIGS.  12 A-B illustrate a front cover  1200  having an outside face  1201 , an inside face  1202 , a switch cavity  1210 , attachment ears  1220 , side latches  1230  and top and bottom catches  1240 . Located on the outside face  1201 , the cavity  1210  is configured to accommodate the switch  1100  (FIGS.  1 A-B). Within the cavity  1210  is a lever slot  1212  that allows the switch lever  1130  ( FIG. 11B ) to pass through the front cover to the actuator  1400  (FIGS.  14 A-B). The lever slot  1212  extends along the cavity  1210  a sufficient distance to allow switch movement between first and second positions, as described above. Also within the cavity  1210  are catch slots  1214  that accommodate and capture the switch latches  1120  ( FIG. 11B ), as described above. The attachment ears  1220  are located at an upper right corner and a diagonally opposite lower left corner (not visible), and each has a fastening aperture that accepts, for example, an attachment screw  305  (FIGS.  3 A-B). The side latches  1230  and top and bottom catches  1240  form the front cover portion of the latch and catch assembly, functionally described with respect to  FIG. 10 , above.  
         [0076]     FIGS.  13 A-B illustrate a SPST contact set  1300  having a throw buss  1310  and a pole buss  1320 . The throw buss  1310  has a first prong  1312 , a flexible throw  1314  and a throw contact  1318 . The pole buss  1320  has a second prong  1322 , a fixed pole  1324  and a pole contact  1328 . The first and second prongs  1312 ,  1322  form the conductive portion of the shielded plugs  930  ( FIG. 9B ). The flexible throw  1314  engages the actuator  1400 , as described with respect to FIGS.  14 A-B, below, which moves the throw between an open position and a closed position (shown). In the closed position, the throw contact  1318  touches and electrically connects with the pole contact  1328 , establishing a conductive path between the first and second prongs  1312 ,  1322 . In the open position, the throw contact  1318  is separated from the pole contact  1328  so that there is no conductive path between the first and second prongs  1312 ,  1322 .  
         [0077]     FIGS.  13 C-D illustrate a SPDT contact set  1301  for a 3-way switch having a second pole buss  1330  in addition to the SPST contact set  1300  (FIGS.  13 A-B). The second pole buss  1330  has a third prong  1332  and a second pole contact  1338 . The flexible throw  1314  engages the actuator  1400 , as described with respect to FIGS.  14 A-B, below, which moves the throw between a first position (shown) and a second position. In a first position, the throw contact  1318  touches and electrically connects with the pole contact  1328 , establishing a conductive path between the first and second prongs  1312 ,  1322 . In a second position, the throw contact  1318  touches and electrically connects with the second pole contact  1338 , establishing a conductive path between the first and third prongs  1312 ,  1332 .  
         [0078]     FIGS.  13 E-F illustrate a DPDT contact set  1302  for a 4-way switch having a second throw buss  1340  and a third pole buss  1350  in addition to the SPDT contact set  1301 . The second throw buss  1340  has a second flexible throw  1344 . The second throw buss  1340  has a fourth prong  1342 , a second flexible throw  1344  and a second throw contact  1348 . The second pole buss  1330  has the third pole contact  1339 , and the third pole buss  1350  has a fourth pole contact  1359 . In a first position, the throw contact  1318  touches and electrically connects with the pole contact  1328 , establishing a conductive path between the first and second prongs  1312 ,  1322 . Also, the second throw contact  1348  touches and electrically connects with the third pole contact  1339 , establishing a conductive path between the third and fourth prongs  1332 ,  1342 . In a second position, the throw contact  1318  touches and electrically connects with the second pole contact  1338 , establishing a conductive path between the first and third prongs  1312 ,  1332 . Also, the second throw contact  1348  touches and electrically connects with the fourth pole contact  1339 , establishing a conductive path between the second and fourth prongs  1322 ,  1342 .  
         [0079]     FIGS.  14 A-B illustrate an actuator  1400  having a front face  1401 , a back face  1402  and a lever slot  1410  generally centered within and passing through the front and back faces  1401 ,  1402 . The actuator  1400  is positioned within the switch module  900  ( FIG. 10 ) so that the front face  1401  is proximate the front cover  1200  ( FIG. 10 ) and the contact set  1300  ( FIG. 10 ) and the back face  1402  is proximate the spring  1000  ( FIG. 10 ) and the back cover  1500  ( FIG. 10 ). The lever slot  1410  accommodates the switch lever tip  1132  ( FIG. 11B ), as described above. The front face  1401  has a pair of upper arms  1420  and a pair of lower arms  1430  extending generally perpendicularly from the front face  1401  so as to engage the contact set  1300  (FIGS.  13 A-B). In particular, the flexible throw  1314  (FIGS.  13 A-B) is engaged between the upper arms  1420 . For a DPDT contact set  1302  (FIGS.  13 E-F), a second flexible throw  1344  (FIGS.  13 E-F) is engaged between the lower arms  1430 . The back face  1402  has a pair of posts  1440  that are slidably retained within back cover guides  1550  ( FIG. 15A ).  
         [0080]     FIGS.  15 A-B illustrate a rear cover  1500  having an inside face  1502 , an outside face  1501 , plug shields  1510 , a key bar  1520 , side catches  1530 , top and bottom latches  1540 , actuator guides  1550 , a spring hold  1560  and contact support structure  1570 . As shown in  FIG. 15B  on the outside face  1501 , the plug shields  1510  advantageously provide the shield portion of the shielded plugs  930  ( FIG. 9B ). Specifically, the plug shields  1510  completely surround all sides of the contact set prongs  1312 ,  1322  (FIGS.  13 A-B). In this manner, the prongs are not exposed when the switch module plugs  930  ( FIG. 9B ) are engaged with the wiring module sockets  1810  ( FIG. 18A ), even when the switch module  900  (FIGS.  9 A-B) is partially separated from the wiring module  1600  (FIGS.  16 A-B). The key bar  1520  is configured to insert into the wiring module ground socket  1820  ( FIG. 18A ), although the key bar  1520  is nonconductive. The key bar  1520  assists proper orientation of the switch module  900  (FIGS.  9 A-B) to the wiring module  1600  (FIGS.  16 A-B). The side catches  1530  provide apertures that accept and engage the side latches  1230  (FIGS.  12 A-B), and the top and bottom latches  1540  insert into and engage the top and bottom catches  1240  (FIGS.  12 A-B) so as to releaseably secure together the front cover  1200  (FIGS.  12 A-B) and the back cover  1500 .  
         [0081]     As shown in  FIG. 15A  on the inside face  1502 , the actuator guides  1550  slidably retain the actuator posts  1440  ( FIG. 14B ). The spring hold  1560  accommodates and retains the spring  1000  ( FIG. 10 ). The contact support structure  1570  consists of slots through the back cover  1500  and structure extending generally normal to the inside face  1502  that support the contact set  1300  (FIGS.  13 A-B). The slots accept the contact set prongs  1312 ,  1322  (FIGS.  13 A-B), which protrude through the back cover  1500  within the plug shields  1510 .  
         [0000]     Terminal-Block Wiring Module  
         [0082]     FIGS.  16 A-B illustrate a terminal-block wiring module  1600  having a functional side  1601  and a wiring side  1602 . The functional side  1601  has structured sockets  1810  and an off-center ground socket  1820 . The structured sockets  1810  accept corresponding functional module shielded plugs, as described with respect to  FIG. 20A , below. The wiring module  1600  is configured to mount within a conventional electrical box (not shown), secured with attachment screws  1605 . A functional module, such as an outlet module  300  (FIGS.  3 A-B) or a switch module  900  (FIGS.  9 A-B) plug into the wiring module functional side  1601 , secured to the wiring module with attachment screws that thread through attachment ears and corresponding module mounts  1930 , as described with respect to  FIGS. 1-2 , above. A power cable (not shown) routed into the electrical box attaches to a terminal block  1640  ( FIG. 16F ) accessible from the wiring module wiring side  1602 , as described with respect to FIGS.  16 E-H, below.  
         [0083]     As shown in FIGS.  16 A-B, a wiring module  1600  advantageously can be installed, wired and tested by journeyman electrician at the rough-in phase of building construction. The wiring module  1600  is mounted within an electrical box according to the type of functional module for which the wiring module  1600  will be wired. If the wiring module  1600  is mounted in a first orientation ( FIG. 1B ), the ground socket  1820  is positioned below-center. If the wiring module is mounted in a second orientation ( FIGS. 2B, 16A ), the ground socket  1820  is positioned above-center. The ground socket  1820  accepts an outlet module ground bar  834  ( FIG. 3B ) or switch module key bar  1520  ( FIG. 9B ), which act as keys. Correspondingly, the ground socket  1820  acts as a block that accepts a functional module key  834  ( FIG. 3B ),  1520  ( FIG. 9B ) only when the functional module is properly oriented with respect to the wiring module  1600  according to module type, such as a switch or outlet. In one embodiment, the wiring module  1600  is mounted with the ground socket  1820  above-center for a switch module  900  (FIGS.  9 A-B) and mounted with the ground socket  1820  below-center for an outlet module  300  (FIGS.  3 A-B), as described in further detail with respect to FIGS.  16 E-H, below.  
         [0084]     FIGS.  16 C-D illustrate a terminal-block wiring module  1600  having terminal guards  1700  that advantageously provide covered access to the terminal set  2100  ( FIG. 21 ). In particular, in a closed position (FIGS.  16 A-B) the terminal guards  1700  protect users from shock and insulate between closely mounted high voltage devices. In an open position (FIGS.  16 C-D), the terminal guards  1700  allow convenient access to the terminal screws  2140  so as to attach or remove power cable wires from the terminal blocks  1640 . As shown in  FIG. 16C , a hinge  1702  allows a terminal guard  1700  to move from a closed position FIGS. ( 16 A-B) to an open position. A latch  1704  presses into a corresponding catch slot  2220 , which retains a terminal guard  1700  in a closed position until it is manually opened. As shown in  FIG. 16D , in one embodiment a swivel mount  1709  ( FIG. 17B ) also allows the terminal guard  1700  to swivel from side to side in an open position, further easing access to the terminal screws  2140 .  
         [0085]     FIGS.  16 E-F illustrate orientation-dependent labels on the wiring module functional and wiring sides, respectively. As described above, the type of functional module to be mounted in the wiring module  1600  determines the mounted orientation of the wiring module  1600  within an electrical box. Color coded labels  1620 ,  1630  on the functional side ( FIG. 16E ) and wiring labels  1650 ,  1660  on the wiring side ( FIG. 16F ) advantageously indicate to the journeyman electrician the correct wiring module  1600  orientation. The color coded labels  1620 ,  1630  also advantageously indicate the correct functional module to be installed or replaced. In particular, as shown in  FIG. 16E , the color coded labels include a switch label  1620  and an outlet label  1630 . The switch label  1620  has an orientation indicator  1622  and corresponding text that specify the wiring module orientation for a switch module  900  (FIGS.  2 A-B). In addition, color boxes  1624  advantageously match color indicators  2310  ( FIG. 23A ) on corresponding switch modules  900 . Further, as shown in  FIG. 16F , the outlet label  1630  has an orientation indicator  1632  and corresponding text that specify the wiring module orientation for an outlet module  300  (FIGS.  1 A-B). Also, color boxes  1634  match an outlet color indicator. In one embodiment, the switch color boxes  1624  are yellow, red and orange matching SP, 3-way and 4-way switch color indicators, respectively. The outlet color boxes  1634  are dark and light blue for full hot and half-hot wiring, matching a blue color indicator for an outlet module. The color boxes  1624 ,  1634  are marked by the journeyman electrician at wiring module installation to visually indicate the module type for which the wiring module  1600  was wired.  
         [0086]     As shown in  FIG. 16F , there are four terminal blocks  1640 , each having terminal labels “ 1 ,” “ 2 ,” “ 3 ” and “4”  1670  identifying the individual terminal blocks T 1 , T 2 , T 3  and T 4  by number. In a switch orientation (shown), switch labels  1650  are advantageously positioned in a manner visually corresponding to each of the individual terminal blocks  1640 . The switch labels  1650  identify switch wiring for each terminal block by switch type SP, 3-way and 4-way. The outlet labels  1660  are upside down in the switch orientation, visually indicating that they are inapplicable. In an outlet orientation (upside down from that shown), outlet labels  1660  are similarly positioned in a manner visually corresponding to each of the individual terminal blocks  1640 . The outlet labels  1660  identify outlet wiring. The switch labels  1650  are upside down in the outlet orientation, visually indicating that they are inapplicable.  
         [0087]     FIGS.  16 G-H illustrate switch and outlet wiring schematics, respectively, corresponding to the terminal labels  1670  ( FIG. 16F ), switch labels  1650  ( FIG. 16F ) and outlet labels  1660  ( FIG. 16F ) described with respect to  FIG. 16F , above. Graphically depicted are groups of four terminals  1690  representing the terminal blocks  1640  ( FIG. 16F ). Also depicted are individual terminal blocks  1691 , corresponding hot, neutral, traveler and switch wires  1692 , and links and gaps  1693  corresponding to removable breakaways  2116 .  
         [0088]     FIGS.  17 A-B illustrate a terminal-block wiring module  1600  having a wiring panel  1800  and a mounting bracket  1900 . The wiring panel  1800  has a front cover  2000 , a back cover  2200 , a terminal set  2100  and terminal guards  1700 . The front cover  2000  and back cover  2200  are secured together with a fastener (not shown). The mounting bracket  1900  further secures the front cover  2000  to the back cover, as described with respect to  FIGS. 18-20 , below. The terminal set  2100  is retained within the wiring panel  1800  and provides terminal blocks  1640  ( FIG. 16F ) for power cable attachment and provides conductive paths between the terminal blocks  1640  ( FIG. 16F ) and structured sockets  1810  ( FIG. 18A ). The mounting bracket  1900  advantageously performs multiple functions including securing the wiring module  1600  to an electrical box (not shown), securing together the front and back covers  2000 ,  2200 , providing a ground bar clip  1902  ( FIG. 19A ) for contact with a module ground bar  834  ( FIG. 3B ) and providing a ground terminal  1907  ( FIG. 19A ) for a ground wire connection.  
         [0089]     As shown in FIGS.  17 A-B, the terminal guards  1700  each have a hinge  1702 , a latch  1704 , a mount  1706 ,  1709  and a grip  1708 . The mount  1706 ,  1709  slides into a corresponding guard slot  2210  ( FIG. 22A ) on each side of the back cover  2200 , which secures each terminal guard  1700  to the wiring panel  1800 . The hinge  1702  advantageously allows a terminal guard  1700  to move between a closed position (FIGS.  16 A-B) blocking inadvertent contact with the terminal blocks  1640  ( FIG. 16F ) and an open position (FIGS.  16 C-D) allowing access to the terminal blocks  1640  ( FIG. 16F ). The latch  1704  presses into a corresponding catch slot  2220  ( FIG. 22A ) on each side of the back cover  2200 , which retains each terminal guard  1700  in a closed position until it is manually opened. A grip  1708  assists in latching the terminal guards  1700 . A stationary mount  1706  ( FIG. 17A ) holds the terminal guards  1700  in alignment with the terminal screws  2140  ( FIG. 21 ). Alternatively, a swivel mount  1709  ( FIGS. 17B ) advantageously allows the terminal guards  1700  to swivel to either side  1601 ,  1602  (FIGS.  16 A-B) of the wiring module for easier access to the terminal screws  2140  ( FIG. 21 ).  
         [0090]     FIGS.  18 A-B illustrate a wiring panel  1800  having a front side  1801  and a back side  1802 . The front side  1801  has structured sockets  1810 , a ground socket  1820  and bracket slots  1830 . The back side  1802  has terminal blocks  1640  ( FIG. 16F ) formed by a terminal set  2100  ( FIG. 21 ) having terminal screws  2140  ( FIG. 21 ) that are accessed through the terminal guards  1700 , as described above.  
         [0091]     FIGS.  19 A-B illustrate a mounting bracket  1900  having a bracket body  1901 , a ground clip  1902  and a ground terminal  1907 . The ground clip  1902  is attached to the bracket body  1901  with a rivet  1905 . The ground terminal  1907  provides a ground termination for a ground wire (not shown). The bracket  1900  has swages  1910 , box mounts  1920  and module mounts  1930 . The bracket  1900  is configured to be disposed around the rear cover  2200  (FIGS.  22 A-B) with the swages  1910  inserted through front cover slots  2020  (FIGS.  20 A-B) and spread against the front cover outside  2001  so as to secure together the front and rear covers  2000 ,  2200 . A fastener  1909  is inserted through the bracket and into the wiring panel front cover  2000 , so as to secure together the front and rear covers  2000 ,  2200 . The box mounts  1920  allow the wiring module  1600  (FIGS.  16 A-B) to be secured to an electrical box (not shown) and are configured to removably engage a box cover ( FIGS. 27-29 ). The module mounts  1930  allow functional modules  300  (FIGS.  3 A-B),  900  (FIGS.  9 A-B) to be secured to the wiring module  1600  (FIGS.  16 A-B). The ground clip  1902  is configured to physically and electrically connect to a module ground bar  834  (FIGS.  8 A-B).  
         [0092]     In an alternative embodiment, the mounting bracket  1900  does not have swages  1910 . Multiple fasteners  1909  are inserted through the mounting bracket  1900  and into the wiring panel front cover  2000 , so as to secure together the front and rear covers  2000 ,  2200 . After the mounting bracket  1900  is attached to the front cover  2000 , ears at the top and bottom of the mounting bracket  1900  are bent over and against the front cover outside  2001  to further secure together the front and rear covers  2000 ,  2200 . Trusses are included across or proximate to folded portions of the mounting bracket  1900  to strengthen the bracket structure. The box mount  1920  may have an alternative shape so as to accommodate a box cover  2700  (FIGS.  27 A-B).  
         [0093]     FIGS.  20 A-B illustrate a front cover  2000  having an outside face  2001  and an inside face  2002 . As shown in  FIG. 20A  on the outside face  2001 , raised guards  2010  and surrounding channels  2014  provide the nonconductive portions of structured sockets  1810  ( FIG. 18A ). Each raised guard  2010  and surrounding channel  2014  are configured to mate with a corresponding plug shield  610  ( FIG. 6B ). In particular, when a functional module is plugged into the wiring module  1600  (FIGS.  16 A-B), shields  610  ( FIG. 6B ),  1510  ( FIG. 15B ) insert into channels  2014 , guards  2010  insert within shields  610  ( FIG. 6B ),  1510  ( FIG. 15B ), and prongs  702  (FIGS.  7 A-B) plug into power clips  2112  ( FIG. 21 ). This interlocking action of the shield plugs  330  ( FIG. 3B ),  930  ( FIG. 9B ) and the structured sockets  1810  ( FIG. 18A ) advantageously provides a fully enclosed shield as an electrical connection is made between a functional module and a wiring module, in addition to tactile feedback and a solid mechanical and electrical connection. Further, the guards  2010  and channels  2014  reduce the chance of an inadvertent contact between a tool, such as a screwdriver tip, and a hot contact within a socket  1810  ( FIG. 18A ). For example, a tool dragged across the wiring panel front side  1801  ( FIG. 18A ) during service will tend to lodge in the channel  2014  or against the raised guard  2010  or both. In a particular embodiment, the shields  610  ( FIG. 6B ),  1510  ( FIG. 15B ) and the corresponding channels  2014  and raised guards  2010  are generally rectangular in shape with rounded corners.  
         [0094]     As shown in  FIG. 20B , the inside face  2002  has swage slots  2020 , a ground aperture  2030  and terminal support structure  2050 ,  2060 . The swage slots  2020  accommodate the mounting bracket swages  1910  ( FIG. 19A ), which assist to secure together the front and back covers  2000 ,  2200 . The ground aperture  2030  accommodates a ground bar  834  ( FIG. 3B ) or key bar  1520  ( FIG. 9B ) as part of a ground socket  1820  ( FIG. 18A ). The support structure  2050 ,  2060  houses the terminal set  2100  ( FIGS. 21 ).  
         [0095]      FIG. 21  illustrates a terminal set  2100  having contact busses  2110 , terminal clamps  2130  and terminal screws  2140 . The contact busses  2110  each have power clips  2112  that provide the conductor portion of the structured sockets  1810  ( FIG. 18A ). The power clips  2112  are configured to physically and electrically connect with module prongs  702  (FIGS.  7 A-B),  1312 ,  1322  (FIGS.  13 A-B). The terminal clamps  2130  and terminal screws  2140  terminate power cables (not shown) to the contact busses  2110 . The terminal clamps  2130  are configured to secure one wire per channel  2132 . Advantageously, this provides a four-wire capacity for each of four terminal blocks  1640  ( FIG. 16F ). In one embodiment, each terminal block  1640  ( FIG. 16F ) is configured for four  14  gauge copper wires or two  12  gauge copper wires. Breakaways  2116  are removable to selectively isolate individual terminal blocks  1640  ( FIG. 16F ).  
         [0096]     FIGS.  22 A-B illustrate a back cover  2200  having an inside face  2202  and an outside face  2201 . The inside face  2202  has mount slots  2210  and catch slots  2220  that retain the terminal guards  1700  ( FIG. 17 ), as described above. The inside face  2202  also has terminal slots  2230  that retain the terminal set. The outside face  2201  is shaped to accommodate the mounting bracket  1900  (FIGS.  19 A-B) and accommodate power cable attachment to the terminal blocks  1640  ( FIG. 16F ). Fixed-Wire Wiring Module  
         [0097]     FIGS.  23 A-B illustrate a fixed-wire wiring module  2300  having a functional side  2301  and a wiring side  2302 . The wiring module  2300  is configured to mount within a conventional electrical box (not shown), secured with attachment screws (not shown) threaded through box mounts  2452 . A functional module, such as an outlet module  300  (FIGS.  3 A-B) or a switch module  900  (FIGS.  9 A-B) plug into the wiring module functional side  2301 , secured to the wiring module  2300  with attachment screws (not shown) that thread through attachment ears (not shown) and corresponding module mounts  2454 , as described with respect to  FIGS. 1-2 , above. A power cable (not shown) routed to the electrical box attaches to pushwire connectors  2370  at the end of fixed wires  2350  extending from the wiring module wiring side  2302 .  
         [0098]     FIGS.  24 A-B illustrate a fixed-wire wiring module  2300  having a front cover  2410 , a back cover  2420 , a terminal set  2430 , a mounting bracket  2450 , a ground bar clip  2460  and fasteners  2470 . The front cover  2410  and back cover  2420  are secured together with the fasteners  2470  and enclose the terminal set  2432 . Advantageously, the mounting bracket  2450  is partially enclosed by, and retained between, the front cover  2410  and back cover  2420  so as to secure the mounting bracket  2450  to, and mechanically and electrically integrate the mounting bracket with, the wiring module  2300 .  
         [0099]     As shown in FIGS.  24 A-B the front cover  2410  has structured sockets  2412 , a ground aperture  2414 , support structure  2416  and fastener posts  2418 . The structured sockets  2412  interlock with functional module shielded plugs and the ground aperture  2414  accommodates a ground bar or key bar as part of a ground socket in a manner as described with respect to FIGS.  20 A-B, above. The support structure  2416  houses the terminal set  2430 . The fastener posts  2418  align with fastener apertures  2424  and accept the fasteners  2470  securing the front cover  2410  to the back cover  2420 .  
         [0100]     Also shown in FIGS.  24 A-B, the terminal set  2430  has power clips  2432 , fixed wire terminals  2434  and breakaways  2438 . The power clips  2432  provide the conductor portion of the structured sockets  2412  and are configured to physically and electrically connect with module prongs in a manner as described with respect to  FIG. 21 , above. The fixed wire terminals  2434  electrically and mechanically connect a striped end of the fixed wires  2350  (FIGS.  23 A-B) to the terminal set  2430 . The breakaways  2438  are removable to selectively isolate individual power clips  2432 .  
         [0101]     Further shown in FIGS.  24 A-B, the mounting bracket  2450  is adapted to a channel extending lengthwise along the front cover  2410  and corresponding support structure extending lengthwise along the back cover  2420 . The mounting bracket  2450  has box mounts  2452 , module mounts  2454 , a ground clip aperture  2456  and a ground terminal  2458 . The box mounts  2452  accept fasteners (not shown) to secure the bracket to an electrical box (not shown). The module mounts  2454  accept fasteners (not shown) to secure a functional module (not shown) to the wiring module  2300 . The ground clip aperture  2456  is adapted to the ground clip  2460 , which connects a functional module ground bar electrically and mechanically to the bracket  2450 . The bracket has an integrated rivet for securing the ground clip  2460  within the aperture  2456 . The ground terminal  2458  electrically and mechanically connects a striped end of a ground one of the fixed wires  2350  (FIGS.  23 A-B) to the bracket  2450 .  
         [0102]     Additionally shown in FIGS.  24 A-B, the back cover  2420  has wire apertures  2422 , fastener apertures  2424  and a breakaway aperture  2426 . The wire apertures  2422  are adapted to the fixed wires  2350  (FIGS.  23 A-B) so as to provide a seal around and strain relief for the fixed wires and access to the terminal set  2430  and ground terminal  2458 . The fastener apertures  2424  accept that portion of the fasteners  2470  that thread into or are otherwise secured to the fastener posts  2418 . The breakaway aperture  2426  allows user access to the breakaways  2438  within an assembled wiring module  2300 . Electrical Box Cover  
         [0103]     FIGS.  25 A-B illustrate an electrical box cover  2500  having a generally planar cover plate  2510 , clamps  2520 , catches  2530 , trusses  2540  and markers  2550 . The cover plate  2510  has a front side  2501  and a back side  2502 . The clamps  2520  are located, one each, generally centered on the top and bottom of the cover plate  2510  and extend generally perpendicularly from the back side  2502 . The catches  2530  are apertures, one for each catch  2530 , that are generally centered on the catches  2520  and extending along the juncture between the catches  2530  and the cover plate  2510 . The trusses  2540  are protrusions on the cover plate  2540  that extend substantially along the length of the front side  2501 , providing structural support to resist bending of the cover plate  2510 . The markers  2550  are generally round protrusions on the front side  2501  of the cover plate  2540  located, one each, proximate the top and bottom of the cover plate  2540 .  
         [0104]     FIGS.  26 A-B illustrate an electrical box  2600  that is covered and uncovered, respectively, by a box cover  2500 , as described with respect to FIGS.  25 A-B, above. The box cover  2500  removably mounts over the electrical box open face  2601  so as to prevent material such as plaster and paint from fouling the wiring module  1600  during the makeup phase of construction. Advantageously, the box cover  2500  mounts generally flush with the electrical box open face  2601  and, hence, generally flush with installed drywall so as not to interfere with drywall construction during the makeup phase. Drywall, once loosely positioned, can be pressed against the box cover  2500 . In doing so, the markers  2550  dimple the drywall, advantageously marking the location of the electrical box  2600  so that drywall cutouts can be accurately made to accommodate the electrical box  2600 .  
         [0105]     As shown in FIGS.  26 A-B, the box cover  2500  is installed on the box mounts  1920  of a wiring module  1600  mounted within the electrical box  2600 . In particular, the clamps  2520  flex somewhat to slide over the box mounts  1920  until the box mounts  1920  insert into corresponding catches  2530 . The box cover  2500  can be easily removed by flexing the clamps  2520  so that a box mount  1920  clears a corresponding catch  2530 .  
         [0106]      FIG. 25  illustrate a  2 -gang electrical box  2500  with overlapping box covers  2500 . The box covers  2500  are configured so that a first portion  2591  of one cover overlaps a second portion  2592  of another cover so as to prevent drywall related material from entering between the covers  2500  and fouling the electrical box  2700  interior.  
         [0000]     Terminal Shield  
         [0107]     FIGS.  28 A-B illustrate a terminal-block wiring module  1600  having a terminal shield  2900  installed on a wiring side  1602  using fasteners  1909 . The terminal shield  2900  advantageously prevents bare copper ground wires (not shown), which typically are connected between the ground terminal  1907  ( FIG. 17A ) and an electrical box (not shown), from inadvertently protruding through the back cover  2200  ( FIG. 17A ) and short circuiting the terminal set  2100  ( FIG. 17A ).  
         [0108]     FIGS.  29 A-B illustrate a terminal shield  2900  having a front side  2901 , a back side  2902  and a spine  2905 . Mounting ears  2910  extend from both ends of the spine  2905 , and shield wings  2920  extend from both sides of the spine  2905 . Breakaway guards  2930  extend from a central portion of each shield wing  2920 . A V-shaped hinge  2935  extending across a portion of each breakaway guard  2930  allows the breakaway guards  2930  to flex somewhat to gain access for removal of one or both of the breakaways  2116  ( FIG. 16F ), as described with respect to FIGS.  16 G-H, above. Mounting apertures  2940  are defined in the mounting ears  2910 , wire apertures  2950  are defined in the shield wings  2920 , and a bracket aperture  2960  is defined in a central portion of the spine  2905 .  
         [0109]     As shown in FIGS.  29 A-B, the terminal shield  2900  is installed with the back side  2902  proximate the wiring module  1600  ( FIG. 28A ) and the front side  2901  distal the wiring module  1600  ( FIG. 28A ). In particular, the spine  2905  fits against the bracket  1900  and the bracket aperture  2960  accommodates protrusions due to the ground clip  1902  ( FIG. 17A ) or its associated fastener. The mounting apertures  2940  accept the fasteners  1909  ( FIG. 28A ), which also secure together the wiring module  1600  ( FIG. 28A ). The shield wings  2920  cover exposed portions of the terminal set  2100  ( FIG. 17A ), and the wire apertures  2950  accommodate wire ends that are connected to the terminal set  2100  ( FIG. 17A ).  
         [0000]     Dimmer Switch Module  
         [0110]     FIGS.  30 A-B illustrate a dimmer switch module  3000  having a power control  3200  and a dimmer control  3500  on a front side  3001  and shielded plugs  3010  and a key bar  3820  on a back side  3002 . The power control  3200  actuates an internal switch that routes electrical power between the shielded plugs  3010  to turn on and off a light, for example. The dimmer control  3500  actuates an internal potentiometer that controls the current between the shielded plugs  3010  to adjust a light&#39;s intensity, for example. The shielded plugs  3010  physically and electrically connect the dimmer switch module  3000  to a wiring module  1600  (FIGS.  16 A-B). The key bar  3820  provides a non-conducting structure that assists in orienting the dimmer switch module  3000  relative to a wiring module.  
         [0111]      FIG. 31  further illustrates the dimmer switch module  3000  having a power control  3200 , a front cover  3300 , a spring  3400 , a dimmer control  3500 , a heat sink  3600 , a dimmer circuit board  3700  and a back cover  3800 . Advantageously, the heat sink  3600  is partially enclosed between the front and back covers  3300 ,  3800  with fins  3620  extending outside the covers  3300 ,  3800  so as to provide a substantial heat dissipating surface area outside of the module  3000 . The module heat sink  3600  is thermally coupled to a triac  3710  mounted on the circuit board  3700  so as to dissipate heat generated by the triac  3710 .  
         [0112]     As shown in  FIG. 31 , the covers  3300 ,  3800  snap together with a latch and catch assembly so as to form a module housing that retains the heat sink  3600 , circuit board  3700  and dimmer control  3500 . The power control  3200  and the dimmer control  3500  are slidably retained by the front cover  3300 . The power control  3200  is movable between an on position and an off position and remains in its manually set position under tension from the spring  3400 . The dimmer control  3500  engages the circuit board  3700  and the front cover  3300  and is movable over a continuum of current setting positions ranging from a low current position to a high current position. The dimmer circuit board  3700  routes electrical power from a wiring module as determined by the power control  3200  and controls the amount of electrical current and power as determined by the dimmer control  3500 . The circuit board  3700  is secured to the back cover  3800  with fasteners  3020 .  
         [0113]     The power control  3200 , front cover  3300 , spring  3400  and dimmer control  3500  are described in detail with respect to  FIGS. 32-35 , below. The heat sink  3600 , dimmer circuit board  3700  and the back cover  3800  are described in detail with respect to  FIGS. 36-38 , below. The dimmer switch circuit is described with respect to  FIG. 39 , below.  
         [0114]     FIGS.  32 A-B illustrate a power control  3200  that is generally rectangular having a front side  3201  and a back side  3202 . The front side  3201  has a finger grip  3210  for manually sliding the power control  3200  between an on position and an off position. The back side  3202  has latches  3220 , a lever  3230  and a knob  3240  extending generally normal to the plane of the back side  3202 . The latches  3220  are adapted to pass through front cover catch slots  3314  (FIGS.  33 A-B), seating the power control  3200  into the front cover  3300  (FIGS.  33 A-B). The lever  3230  inserts through a front cover power control slot  3312  (FIGS.  33 A-B) and a heat sink slot  3640  (FIGS.  36 A-B) so as to actuate a circuit board switch  3720  (FIGS.  37 A-C). In particular, the lever  3230  has a vertical face  3232  and an angled face  3234  at its tip. The vertical face  3232  actuates the switch  3720  ( FIGS. 37A , C) to an off position and the angled face  3234  actuates the switch  3720  ( FIGS. 37A , C) to an on position. The knob  3240  presses against the spring  3400  (FIGS.  34 A-B) so as to provide tension to the power control  3200  and to define on and off positions.  
         [0115]     FIGS.  33 A-B illustrate a front cover  3300  having an outside face  3301 , an inside face  3302 , a power control cavity  3310 , a dimmer lever slot  3320 , side latches  3330  and posts  3340 . Located on the outside face  3301 , the power control cavity  3310  is configured for the power control  3200  (FIGS.  32 A-B). Within the power control cavity  3310  are a power lever slot  3312 , catch slots  3314  and spring holders  3316 . The power lever slot  3312  allows the power control lever  3230  (FIGS.  32 A-B) to pass through the front cover  3300  to the circuit board  3700  (FIGS.  37 A-C). The catch slots  3314  retain the power control latches  3220  (FIGS.  32 A-B), as described above. The spring holders  3316  are configured to retain the spring  3400  (FIGS.  34 A-B) within the power control cavity  3310 . Also located on the outside face  3301 , the dimmer lever slot  3320  allows a dimmer lever  3510  (FIGS.  35 A-B) to protrude through the front cover  3300  so that the dimmer control  3500  (FIGS.  35 A-B) can be manually positioned. The side latches  3330  insert into back cover side catches  3830  (FIGS.  38 A-B) so as to secure together the front cover  3300  and the back cover  3800  to form a housing, as described above.  
         [0116]     FIGS.  34 A-B illustrate a spring  3400 , which provides tension and a position retaining mechanism for the power control  3200  (FIGS.  32 A-B). The spring  3400  has a curved middle  3410 , flat surfaces  3420  extending from the middle  3410  and folded ends  3430 . The middle  3410  pushes against the power control knob  3240  (FIGS.  32 A-B) forcing the knob  3240  (FIGS.  32 A-B) to one of the flat surfaces  3420  so as to retain the power control  3200  (FIGS.  32 A-B) in either an on or off position until manually actuated. The ends  3430  extend perpendicularly to the flat surfaces  3420  so as to grasp the spring holders  3316  (FIGS.  33 A-B).  
         [0117]     FIGS.  35 A-B illustrate a dimmer control  3500  having a dimmer lever  3510 , a clip  3520  and guides  3530 . The dimmer lever  3510  extends perpendicularly from the guides  3530  and protrudes through the dimmer lever slot  3320  (FIGS.  33 A-B) so as to be accessible for manual actuation. The clip  3520  defines a generally centered clip aperture  3522  that fits over and retains a potentiometer control  3732  (FIGS.  37 A-C). The guides  3530  are supported by the front cover inside face  3302  (FIGS.  33 A-B) and extend beyond the ends of the dimmer control slot  3320  (FIGS.  33 A-B). As the dimmer control  3500  is slidably actuated, the potentiometer control  3732  (FIGS.  37 A-C) is slideably actuated so as to adjust the resistance of the potentiometer  3730  (FIGS.  37 A-C), dimming a light or otherwise changing current through the dimmer module  3000 , as described below.  
         [0118]     FIGS.  36 A-B illustrate a heat sink  3600  having a body  3610 , fins  3620  extending generally perpendicularly from and folded back toward the body  3610 , attachment ears  3630 , a slot  3640 , a potentiometer aperture  3650 , latch apertures  3660  and thru holes  3670 . The attachment ears  3630  define apertures  3632  that accept fasteners so that the dimmer switch module  3000  (FIGS.  30 A-B) can be secured to a wiring module. The slot  3640  passes the power control lever  3230  (FIGS.  32 A-B) as described above. The potentiometer aperture  3650  accommodates the potentiometer  3730  (FIGS.  37 A-C). The latch apertures  3660  pass the front cover latches  3330  (FIGS.  33 A-B) to the back cover catches  3830  (FIGS.  38 A-B). The thru holes  3670  allow tool access to the circuit board fasteners  3020  ( FIG. 31 ).  
         [0119]     FIGS.  37 A-C illustrate a circuit board  3700  having a printed circuit substrate  3705  with mounted components  3710 - 3740  on a front side  3701  and prongs  3750  extending from a back side  3702 . The major mounted components are a triac  3710 , a switch  3720 , a potentiometer  3730  and a coil  3740 , described below. The triac  3710  is secured to the heat sink, as shown in  FIG. 31 , above. The prongs  3750  form the conductive portions of the shielded plugs  3010  (FIGS.  30 A-B).  
         [0120]     FIGS.  38 A-B illustrate a back cover  3800  having an inside face  3802 , an outside face  3801 , shields  3810 , a key bar  3820 , side catches  3830  and mounting posts  3840 . As shown in  FIG. 38B  on the outside face  3801 , the shields  3810  provide the shield portion of the shielded plugs  3010  (FIGS.  30 A-B). In particular, the shields  3810  completely surround all sides of the prongs  3750  (FIGS.  37 A-C) so that the prongs  3750  (FIGS.  37 A-C) are not exposed while the dimmer switch module  3000  is engaged with a wiring module, even when the dimmer switch module  3000  is partially separated from a wiring module. The key bar  3820  is configured to insert into a wiring module ground socket so as to orient the dimmer switch module  3000 . The side catches  3830  accept and engage the side latches  3330  (FIGS.  33 A-B) so as to secure the front cover  3300  to the back cover  3800 . As shown in  FIG. 38A  on the inside face  3802 , the mounting posts  3840  define apertures that accommodate fasteners  3020  ( FIG. 31 ) that attach the circuit board  3700  ( FIG. 37A -C) to the back cover  3800 .  
         [0121]      FIG. 39  illustrates a dimmer circuit  3900 , such as implemented on the circuit board  3700 , described above. The dimmer circuit  3900  has the major components identified with respect to FIGS.  37 A-C including a triac  3710 , on/off switch  3720 , potentiometer  3730  and coil  3740 . The triac  3710  is a power control element for the circuit  3700 . The switch  3720  enables and disables the circuit  3700 . The coil  3740  and a first RC filter  3910  suppress RF (radio frequency) electrical noise. A current limiting resistor  3920  protects the potentiometer  3730  in the event of a short circuit. A second RC filter  3940  smoothes the current input to a diac  3930 . In operation, the triac  3710  is initially nonconducting. The potentiometer  3730  variably sets the trigger point of a diac  3930  within an AC power cycle. In particular, the capacitor  3950  is charged through the potentiometer  3730  until the trigger level of the diac  3930  is reached and it fires. This causes the triac  3710  to be conductive so that current flows between the prongs  3750 . The triac  3710  will remain in a conductive mode until the current flowing between the prongs  3750  is lower than the triac hold current at the end of a half period of the AC power cycle.  
         [0000]     Other Functional Modules  
         [0122]     Although described above with respect to outlet and switch modules, the electrical distribution system may operate in conjunction with a variety of functional modules providing various electrical functions, such as security modules, data transfer modules, computing modules, home entertainment modules and intelligent home product modules to name a few. For example, a security module may incorporate a video camera or motion sensor. A data transfer module may incorporate data storage devices, wireless transceivers or AC power line transceivers. A computing module may incorporate a microprocessor, a data entry or display device, for example. A home entertainment module may work in conjunction with speakers, LCD panels or plasma TVs. A home product module, for instance, may incorporate a microcontroller and a wireless or an AC power line transceiver for appliance control.  
         [0123]     A functional module has been disclosed in detail in connection with various embodiments. These embodiments are disclosed by way of examples only and are not to limit the scope of the claims that follow. One of ordinary skill in the art will appreciate many variations and modifications.