Patent Publication Number: US-8982540-B1

Title: Power safety assembly

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 13/622,778, filed Sep. 19, 2012, which claims priority to U.S. Provisional Application No. 61/539,211, filed Sep. 26, 2011, the subject matter of which is hereby incorporated by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to enclosing power components in an enclosure for electrical equipment, and more particularly to a vented cover for enclosing power components in an enclosure for electrical equipment. 
     BACKGROUND OF THE INVENTION 
     Power terminals, contacts, conductors or other components operating at 50 volts or more in an enclosure need to be segregated and covered to ensure that personnel who are not trained do not have access to these terminals, contacts, conductors or other components. Generally, the power is turned off during maintenance of the components located in the enclosure. It would be desirable to eliminate the need to turn off the power to the enclosure by providing a method of segregating and covering the power terminals, contacts, conductors or other components operating at 50 volts or more in the enclosure. Therefore, allowing personnel who are trained to have access to the power terminals, contacts, conductors or other devices operating at less than 50 volts. It would also be desirable to maximize the amount of space available for mounting these power terminals, contacts, conductors or other components in the enclosure. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to an enclosure for electrical equipment. The enclosure includes a power plate assembly and a vented cover installed over the power plate assembly. The power plate assembly includes a gland plate, gasket strips surrounding the gland plate for creating a moisture resistant connection with the enclosure and a standoff plate secured to the gland plate. Electrical components operating at 50 or more volts are secured to the power plate assembly. Since the vented cover is installed over the power plate assembly, the vented cover separates the electrical components in the enclosure that operate at 50 volts or more from electrical components installed in the enclosure that operate at less than 50 volts. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front view of an enclosure for electrical equipment with a front cover removed. 
         FIG. 2  is an exploded view of a power plate assembly to be installed in the enclosure of  FIG. 1 . 
         FIG. 3  is a front exploded view of the power plate assembly of  FIG. 2  with a DIN rail positioned to be installed. 
         FIG. 4  is front exploded view of the power plate assembly of  FIG. 3  with electrical components positioned to be installed. 
         FIG. 5  is an exploded view of the power plate assembly of  FIG. 4  positioned to be installed in the enclosure. 
         FIG. 6  is an exploded view of the power plate assembly installed in the enclosure of  FIG. 5  with a vented cover positioned to be installed over the power plate assembly. 
         FIG. 7  is a top perspective view of the power plate assembly and vented cover of  FIG. 6  installed in the enclosure. 
         FIG. 8  is a front perspective view of the power plate assembly of  FIG. 5  with power entry through the gland plate. 
         FIG. 9  is a back perspective view of the power plate assembly of  FIG. 8  with the vented cover installed on the power plate assembly. 
         FIG. 10  is a front view of an alternative enclosure for electrical equipment with a front cover removed. 
         FIG. 11  is a front exploded perspective view of the enclosure of  FIG. 10  with an alternative vented cover positioned to be installed in the enclosure. 
         FIG. 12  is a perspective view of the alternative vented cover of  FIG. 11 . 
         FIG. 13  is a side view of the enclosure with the alternative vented cover of  FIG. 11  installed over the power plate assembly. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates an enclosure for electrical equipment  20  with the front cover of the enclosure removed. The left side  22  of the enclosure  20  includes a gland plate  32  with a DIN rail  44  mounted to a DIN rail standoff plate  38  (see  FIG. 3 ) which can be pre-wired as a sub-assembly prior to installation in the enclosure  20 . The enclosure  20  also includes power terminals, contacts, conductors or other components operating at less than 50 volts mounted to a DIN rail on the enclosure back plate  24 . Although a DIN rail is utilized in this enclosure, other industrial standard mounting techniques are acceptable. This enclosure illustrates the gland plate  32  located on the left side of the enclosure; however, the gland plate could be located on other walls of the enclosure. 
       FIG. 2  illustrates elements of the power plate assembly  30  that is installed in the side  22  of the enclosure  20  of  FIG. 1 . The power plate assembly  30  includes a gland plate  32  with a plurality of countersunk rivet holes  34  positioned near the edges, gasket strips  36  and a DIN rail standoff plate  38 . The gasket strips  36  are applied to the outside perimeter of the gland plate  32 . The gasket strips are ¼ inch in height with the gland plate  32  having a flange with a height of % inch to limit the compression of the gasket to 50% when installed in the enclosure  20 . The gasket strips  36  allow the power plate to create a dust and moisture resistant connection with the enclosure  20 . The DIN rail standoff plate  38  is secured to the gland plate  32  via a plurality of flat head rivets  42  to form the power plate assembly  30 . 
       FIG. 3  illustrates the power plate assembly  30  with a DIN rail  44  cut to the desired length and positioned to be installed on the DIN rail standoff plate  38 . The DIN rail standoff plate  38  has threaded studs  40  pressed in place to mount the DIN rail  44  with hex nuts  46  or other industry standard fasteners. Once the DIN rails  44  are secured to the DIN rail standoff plate  38 , the components  48  may be installed. 
       FIG. 4  illustrates typical components  48  being installed on the DIN rail. For example, a power supply  50 , a surge or filter  52 , a DC UPS  54  and a fuse  56  may be installed on the power plate assembly  30 . The power plate assembly  30  utilized in this enclosure also includes an optional ground bar  58  for easier termination. The power plate assembly  30  may also include optional push-in place cable retaining clips  60  to route and protect wiring routing thereon. The power plate assembly  30  can be pre-wired before it is installed in the side  22  of the enclosure  20 . 
       FIG. 5  illustrates the power plate assembly  30  with the installed electrical components  48  positioned to be installed in the enclosure  20 . The power plate assembly  30  is installed in the side  22  of the enclosure  20  with hex nuts or other industry standard fasteners. Once installed, the final wiring is completed within the enclosure. Next, as illustrated in  FIG. 6 , a vented or perforated cover  90  is installed over the power plate assembly  30  inside the enclosure  20 . The vented cover includes openings or holes in at least one of the top and sides of the cover, as desired. The power wiring enters and exits the vented cover  90  through removable rubber grommets  92  positioned around the cover  90 . The vented cover  90  is secured in place with tamper resistant fasteners to prevent removal by personnel who are not trained to access or maintain the power terminals, contacts, conductors or other components located within the power plate assembly. The vented cover  90  allows heat to dissipate from the components. Furthermore, the conductors operating at 50 volts or more within the enclosure and outside the vented cover are enclosed in a protective sheath to maintain the separation of these conductors from the area operating at less than 50 volts. 
       FIG. 7  illustrates the power plate assembly  30  and vented cover  90  fully installed in the enclosure  20 . As a result, the power terminals, contacts, conductors or other components operating at 50 volts or more are separated from power terminals, contacts, conductors, or other components operating at less than 50 volts. Therefore per industry standards, the shock hazard of the power terminals, contacts, conductors or other components operating at less than 50 volts is mitigated. Furthermore,  FIG. 7  also illustrates an optional LED door switch  100  that will be wired to the covered power supplies through the grommets in the vented cover. This optional LED door switch operates at less than 50 volts. 
       FIGS. 8 and 9  illustrate the power plate assembly  30  and the vented cover  90  of the present invention. Conductors operating at 50 volts or more can be connected to the outside of the power plate assembly to allow the power entry  94  through the gland plate  32  and under the vented cover plate  90 . Thus, the vented cover plate  90  completely covers the incoming conductors operating at 50 volts or more. 
       FIGS. 10-13  illustrate an alternative enclosure  120  with a power plate assembly  30  and vented or perforated cover  190 .  FIG. 10  illustrates a pre-configured enclosure. All of the power terminals  150 , contacts, conductors or other components operating at 50 volts or more are mounted on the enclosure back plate  122  at the bottom  124  of the enclosure  120  to allow a single vented cover  190  to be installed over the components. The components outside of the covered area operate at less than 50 volts. 
       FIG. 11  illustrates the enclosure  120  with a vented cover  190  positioned to be installed over the removable gland plate  132  and the power terminals  150 , contacts, conductors or other components operating at 50 volts or more that are mounted to the DIN rail  144  (see  FIG. 10 ) on the enclosure mounted to back plate  122 . The vented cover  190  will be fastened in place with tamper resistance fasteners. As illustrated, incoming conductors operating at 50 volts or more  210  are brought into the zone enclosure  120  through a fitting installed on the gland plate  132 . As a result, the power terminals, contacts, conductors or other components operating at 50 volts or more are separated from power terminals, contacts, conductors, or other components operating at less than 50 volts. Therefore per industry standards, the shock hazard of the power terminals, contacts, conductors or other components operating at less than 50 volts is mitigated. 
       FIG. 12  illustrates the vented cover  190 . The vented cover  190  allows heat generated from the power terminals  150 , contacts, conductors or other components operating at 50 volts or more to dissipate. As discussed above, the vented cover  190  also separates the power terminals, contacts, conductors or other components operating at 50 volts or more from power terminals, contacts, conductors, or other components operating at less than 50 volts. The vented cover  190  can include grommets. Grommet  192  for entry of power for terminals, contacts, conductors or other components operating at 50 volts or more (if the power entry is not through the gland plate  132 ) and a grommet  194  for an exit of power terminals, contacts, conductors, or other components operating at less than 50 volts can be located at various places on the cover. The vented cover  190  also includes a back flange  196  to attach to the enclosure bottom gland plate threaded studs, flanged edges  198  for rigidity, and a bottom flange  200  to attach to the enclosure back plate  122 . Furthermore, the conductors operating at 50 volts or more within the enclosure and outside the vented cover are enclosed in a protective sheath to maintain the separation of these conductors from the area operating at less than 50 volts. 
       FIG. 13  illustrates a cross section of the enclosure  120  with the vented cover  190  positioned over the power terminals  150 , contacts, conductors or other components operating at 50 volts or more. The vented cover is mounted on the back plate  122  and secured to the gland plate  132  via a threaded stud. Although this enclosure illustrates the vented cover, gland plate and the power terminals, contacts, conductors or other components operating at 50 volts or more located at the bottom of the enclosure, these components could be located on different faces of the enclosure. 
     The enclosure for electrical equipment power plate assembly of the present invention provides protection against accidental contact with power terminals, contacts or conductors operating at 50 volts or more by personnel who are not trained to access or maintain these terminals, contacts or conductors by totally enclosing these components under a tamper resistant cover. The power plate assembly completely encloses incoming wiring operating at 50 volts or more by providing a location for the incoming conductor entry into the gland plate of the power plate assembly. The power plate assembly provides the ability to access the enclosure without removing power to the terminals, contacts or conductors operating at less than 50 volts and maximizes the available space on the enclosure back plate for equipment by moving the components operating at 50 volts or more to the side or bottom of the enclosure. Thus, the power plate assembly and the vented cover of the present invention segregate and cover power terminals, contacts or conductors operating at 50 volts or more form personnel who are not trained to access or maintain these terminals, contacts or conductors while maximizing the available space on the enclosure back plate. 
     Furthermore while the particular preferred embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the teaching of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as limitation.