(19)
(11)EP 3 078 032 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
06.05.2020 Bulletin 2020/19

(21)Application number: 13898604.7

(22)Date of filing:  03.12.2013
(51)Int. Cl.: 
C25D 11/02  (2006.01)
C25D 3/30  (2006.01)
C25D 5/12  (2006.01)
C25D 11/24  (2006.01)
C23C 18/16  (2006.01)
C23C 18/54  (2006.01)
C25D 3/12  (2006.01)
C25D 5/02  (2006.01)
C25D 11/16  (2006.01)
C25D 17/06  (2006.01)
C25D 11/00  (2006.01)
C25D 11/08  (2006.01)
(86)International application number:
PCT/US2013/072839
(87)International publication number:
WO 2015/084331 (11.06.2015 Gazette  2015/23)

(54)

SYSTEM FOR INSULATING HIGH CURRENT BUSBARS

SYSTEM ZUR ISOLIERUNG VON HOCHSTROMSCHIENEN

SYSTÈME D'ISOLATION DE BARRES OMNIBUS À COURANT ÉLEVÉ


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(43)Date of publication of application:
12.10.2016 Bulletin 2016/41

(73)Proprietor: Schneider Electric IT Corporation
West Kingston, RI 02892 (US)

(72)Inventors:
  • SILBERBAUER, Kristian
    6760 Ribe (DK)
  • ANDERSEN, Claus Aabjerg
    6000 Kolding (DK)

(74)Representative: Murgitroyd & Company 
Murgitroyd House 165-169 Scotland Street
Glasgow G5 8PL
Glasgow G5 8PL (GB)


(56)References cited: : 
WO-A1-2009/064060
CN-U- 202 595 307
US-A- 3 603 539
US-A- 4 681 666
US-A1- 2004 007 460
US-A1- 2007 212 558
US-B2- 6 911 139
US-B2- 8 496 767
CN-A- 102 691 090
US-A- 1 404 674
US-A- 3 641 473
US-A- 4 844 779
US-A1- 2006 076 241
US-A1- 2013 043 135
US-B2- 8 469 735
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    BACKGROUND OF DISCLOSURE


    1. Field of Disclosure



    [0001] Embodiments of the disclosure relate generally to busbars used in equipment racks, and more specifically, to methods of partially insulating high current busbars.

    2. Discussion of Related Art



    [0002] Centralized data centers for computer, communications and other electronic equipment have been in use for a number of years. More recently, with the increasing use of the Internet, large scale data centers that provide hosting services for Internet Service Providers (ISPs), Application Service Providers (ASPs) and Internet content providers have become increasingly popular. It is often desirable to operate equipment within data centers seven days a week, 24 hours per day, with little or no disruption in service. To prevent any disruption in service, it is common practice in data centers to use uninterruptible power supplies (UPSs) to ensure that the equipment within the data centers receives continuous power throughout any black out or brown out periods. Typically, data centers are equipped with a relatively large UPS at the main power distribution panel for the facility. Often, the UPS is selected to have sufficient capacity to meet the power requirements for all of the equipment within the facility.

    [0003] In certain circumstances, the UPS may require large conductors or busbars, which can carry large currents and high voltages. In some situations, the busbars need to be insulated to avoid short circuits, and in some situations, the busbars need a coating on the contact surfaces due to Underwriters Laboratories (UL) regulations. Presently, there are several methods to insulate busbars. One such method is to apply an epoxy coating to the busbar so that the busbar can withstand high voltages. The coating applied to the surfaces of the busbar is resistant to oxidation over time, and thereby impedes conductivity, which can lead to a thermal runaway. However, epoxy coatings can be expensive. There are many other coatings to insulate the busbar. One such method is to paint the busbar with an anti oxidizing paste before assembly. Another method is to metalize the surface of the busbar with a metal to provide a low contact resistance and avoid excessive oxidation. Silver, tin, and chrome are common metals for surface coating. Typically, the busbar is coated on the full surface. However, coating the busbar with silver, tin or chrome (such as Chrome III) can be expensive as well. Moreover, these processes may not be recognized by UL. Other methods may include sleeves and large air gaps.

    [0004] Busbars have historically been made from copper, and copper is still a desirable material for busbars. However, due to rising costs of raw material, aluminum has become more common. Unlike copper, which can be used uncoated up to relatively large sizes, aluminum typically requires some form of surface coating on the contact areas due to the quick oxidation of the aluminum surfaces when exposed to air. Coating busbars with epoxy or similar for insulation purposes is a very effective way of adding security and functionality to the busbar, and the technique is state of the art also for medium voltage.

    [0005] Aluminum has been used as conductors for decades. Also, a process exist today where parts of an aluminum surface are coated with a metal plating for conducting and other parts are anodized (non-conducting). One process employs the use of Chrome III, which is used to metalize the surfaces of the busbar. A special tape may be applied where conducting is intended. Where no tape is applied, insulation is made by removing the Chrome III in a strong acid followed by an anodizing process. Chrome III is not recognized by Underwriters Laboratories as is tin and silver and nickel.

    [0006] CN102691090 describes a fixed aluminum alloy profile clamping apparatus, which relates to an improvement on the structure of an aluminum alloy profile clamping apparatus.

    SUMMARY OF DISCLOSURE



    [0007] One aspect of the present disclosure is directed to a method of treating a surface of an aluminum busbar. In one embodiment, the method comprises: pre-conditioning the surface of the busbar; anodizing one portion of the surface of the busbar; and plating another portion of the surface of the busbar with at least one metal.

    [0008] Embodiments of the method further may include applying a protective layer on the one portion of the surface of the busbar. The protective layer may be fabricated from PTFE. The sealing jig may be removed after applying the protective layer. The plating process may include plating the another portion of the busbar with at least one zinc coating. The plating process further may include plating the another portion of the busbar with a nickel coating. The plating process further may include plating the another portion of the busbar with a tin coating. The plating process further may include neutralizing the another portion of the busbar, and subjecting the another portion of the busbar to a post dip step. Anodizing one portion of the surface of the busbar may include securing the busbar in a sealing jig. Anodizing one portion of the surface of the busbar further may include de-smutting the busbar with an acid solution. Anodizing one portion of the surface of the busbar further may include applying an anodizing agent. Anodizing one portion of the surface of the busbar further may include coloring the busbar with a water/dye solution and sealing the busbar with water.

    [0009] Another aspect of the present disclosure is directed to a fixture used to secure a busbar for a treatment process. In one embodiment, the fixture comprises a jig top configured to engage a top surface of the busbar, a jig bottom configured to engage a bottom surface of the busbar, and crab pliers configured to apply a force on the jig top and the jig bottom to secure the busbar in place.

    [0010] Embodiments of the fixture further may include an anode for performing an anodizing process. The anode may extend through the jig bottom so that an end of the anode is exposed on an upwardly facing surface of the jig bottom. The fixture further may include a directional pin to orient the jig in a correct position. The directional pin may extend from an upwardly facing surface of the jig bottom, with the directional pin being received within an opening formed in the busbar. The fixture further may include a seal provided on a downwardly facing surface of the jig top and a seal provided on an upwardly facing surface of the jig bottom. The crab pliers may be permanently attached to the jig top and jig bottom. The jig top and the jig bottom may be fabricated from solid material with good dimensional stability.

    [0011] In a first aspect of the invention there is provided an apparatus comprising a busbar and a fixture used to secure the busbar for a treatment process as claimed in the appended claim 1. In another aspect of the invention there is provided a method of treating a surface of an aluminum busbar as claimed in appended claim 4.

    BRIEF DESCRIPTION OF DRAWINGS



    [0012] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures is represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. In the drawings:

    FIG. 1 is a perspective view of a top surface of a portion of a busbar having a treated area;

    FIG. 2 is a perspective view of a bottom surface of the portion of the busbar having a treated area;

    FIG. 3 is a table showing a process flow chart of a method of treating surfaces of a busbar versus processes involving anodizing and tin plating;

    FIG. 4 is a perspective view of crab pliers used to perform the method of treating surfaces of the busbar;

    FIG. 5 is a perspective view of a jig shown prior to being secured to an end of the busbar;

    FIG. 6 is a perspective view of the jig showing an exposed anode; and

    FIG. 7 is a table showing a process flow chart of two additional methods for treating surfaces of a busbar.


    DETAILED DESCRIPTION



    [0013] This disclosure 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 principles set forth in this disclosure are capable of being provided in other embodiments and of being practiced or of 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 as well as additional items.

    [0014] Uninterruptible power supplies are used to provide conditioned and continuous power to equipment provided within data centers, especially throughout any black out or brown out periods. As mentioned above, data centers are equipped with relatively large UPSs at the main power distribution panel for the facility. In certain embodiments, a configurable rack in the form of an uninterruptible power supply includes a frame assembly having a front frame defining a front of the configurable rack, a rear frame defining a rear of the configurable rack, and side frame members that connect the front frame to the rear frame. The frame assembly is a box-shaped structure having, in addition to the front and back, two sides, a top and a bottom. The front frame and the rear frame are each configured to receive electronic modules in stacked relation along a height of the frame. In certain embodiments, the modules may be rack-mounted or mounted on rails or slides within the interior of the frame assembly. The configurable rack may include power modules and batteries to form an uninterruptible power supply, and other pieces of equipment required to operate the uninterruptible power supply. These modules are rack-mounted in the well-known manner.

    [0015] Busbars may be used to provide power to the modules positioned within the configurable rack. Busbars are also used in many electrical power distribution devices, such as power modules, switching apparatus, distribution apparatus, and batteries. In certain embodiments, the busbar may be configured as a strip or bar of conductive material, such as copper, aluminum, or brass. According to the invention, the busbar is made of aluminium. A primary purpose of the busbar is to conduct electricity. A cross-sectional size of the busbar may be selected to determine a maximum amount of current that can be safely carried. Busbars can be configured to small or large cross-sectional areas. Busbars are typically either flat strips or hollow tubes as these shapes allow heat to dissipate more efficiently due to their high surface area to cross-sectional area ratio. Reference can be made to U.S. Patent Application Publication No. 2012/0170175 A1, which discloses a configurable rack having a busbar backplane to provide power to modules positioned within the configurable rack.

    [0016] A busbar may either be supported on insulators, or else insulation may completely or partially surround an exterior surface of the busbar. One or more techniques of the present disclosure are directed to adding insulation to aluminum busbars with the use of anodizing and plating to the busbars in select contact areas. Contact areas are defined as areas that are bolted against other busbars, cables or similar constructions. The insulating properties of anodized aluminum are to be considered as a ceramic insulator, which can be combined with other insulators. An object of the present disclosure is to create a relatively inexpensive insulated busbar that can be bolted to other aluminum busbars or to copper busbars without electro-galvanic issues and that can occur with known plating processes. FIG. 1 illustrates a portion of a busbar generally indicated at 10 having a top surface 12 with an anodized are 14 and a tin plated area 16. As shown, the tin plated area 16 covers the entire top surface at the end of the busbar 10. FIG. 2 illustrates a bottom surface 18 of the portion of the busbar 10 having an anodized area 20 and discrete tin plated areas each indicated at 22.

    [0017] Referring to FIG. 3, one embodiment of a method of treating a busbar is generally indicated at 30. As shown, the method includes a pre-conditioning process generally indicated at 32, an anodizing process generally indicated at 34, a PTFE application step generally indicated at 36, and a plating process generally indicated at 38. Combine anodizing and plating processes into a simple process flow line so degreasing, etching and de-smutting is shared for both processes. In one embodiment, the pre-conditioning process 32 includes degreasing the busbar with a mild alkaline having a pH of about 12 at a temperature of 50 °C to 80 °C for 60 to 300 seconds. Next, the busbar is rinsed with an appropriate rinsing solution. The pre-conditioning process 32 further includes an alkaline etch with a strong alkaline having a pH of about greater than 13 at a temperature of 60 °C to 70° for 5 to 120 seconds. Next, the busbar is rinsed to conclude the pre-conditioning process 32. The pre-conditioning process 32 ensures that the busbars are kept continuously kept wet (wet in wet) from the start of the process to the end of the process.

    [0018] Next, the busbar is treated by the anodizing process 34. However, prior to going through anodizing, the busbar is held in place by a fixture or sealing jig, which, in one embodiment, is a spring-loaded device that suspends the busbar during the anodizing process 34. The sealing jig is configured to perform within a wet environment so that the busbar is continuously wet during activation and deactivation, and to expose select areas for anodizing. A description of the sealing jig will be provided with reference to FIGS. 4 and 5, below.

    [0019] In the anodizing process 34, exposed aluminum develops by nature a thin layer of aluminum oxide on surfaces of the aluminum busbar that is non conductive. In many instances, the aluminum busbars are joined together with a deoxidizing gel that removes this oxide layer before joining the busbars together. UL allows these joining to be up to 75 °C during type approval of a product. In one embodiment, the method 30 includes a mixed combination of surface treatments that make it possible to assign conductivity or non-conductivity to the surface of aluminum busbars by use of the sealing jigs, and a mixture of two coating techniques. The anodizing process 34 is a process to make the selected surface or surfaces of the aluminum busbar non-conductive. The natural oxide layer may be electrically reinforced and made thicker. UL recognizes anodizing as a ceramic insulation, and is therefore deemed a very safe and reliable insulator.

    [0020] It should be understood that the anodizing process 34 may include any suitable process to anodize the selected surfaces of the busbar, and still provide the beneficial effects desired. With any anodizing process 34, the busbar requires cleaning, in either a hot soap cleaner or in a solvent bath, and may be etched or brightened in a mix of acids. The anodized aluminum layer is grown by passing a direct current through the anodizing step through an electrolytic solution, with the aluminum busbar serving as the anode (the positive electrode). The current releases hydrogen at the cathode (the negative electrode) and oxygen at the surface of the aluminum anode, thereby creating a build-up of aluminum oxide on the surface of the busbar. Aluminum anodizing is usually performed in an acid solution, which slowly dissolves the aluminum oxide. The acid action is balanced with the oxidation rate to form a coating with nanopores, which are often filled with colored dyes and/or corrosion inhibitors before sealing.

    [0021] As shown in FIG. 3, in one embodiment, the anodizing process 34 includes de-smutting the selected surfaces of the busbar with an acid solution having a pH value less than 1. In certain embodiments, the acid solution is nitric acid (HNO3) having a solution concentration of approximately 50 %. Next, the surfaces of the busbar are rinsed with an appropriate rinsing solution. The surfaces of the busbar are next subjected to an anodizing agent having a pH of approximately 1 at 20 °C at a current of 1.2 to 2 A/dm2 for one or more minutes. In certain embodiments, the anodizing agent is sulfuric acid (H2SO4) having a solution concentration of approximately 20 %. The anodizing process 34 further includes rinsing the busbar with an appropriate solution, and coloring the busbar with a water/dye solution having a pH between 7 and 8 at 20 °C. And finally, the anodizing process 34 includes rinsing the busbar with an appropriate solution, sealing the busbar with water having a pH between 7 and 8 at a temperature of 80 °C to 95 °C, and performing a final rinsing step on the busbar.

    [0022] As discussed, the anodizing process 34 is performed with the busbar being held in place by the sealing jig configured to expose selected surfaces of the busbar for anodizing. After the anodizing process 34, a PTFE layer, or some other similar product, is applied during the PTFE application step 36 on top of the surfaces treated by the anodizing process. The PTFE layer prevents the anodized treated surface from being eaten away by the stripping step of the plating process, which will be described in greater detail below. After applying the PTFE layer, the sealing jig is removed to enable the application of the plating process.

    [0023] Still referring to FIG. 3, the plating process 38 includes plating the busbar with two zinc coatings, a nickel coating and a tin coating. The zinc coatings act as an enabler for metallization. Nickel plating provides a more uniform layer thickness over the surface of the busbar. Nickel plating is self-catalyzing process; the resultant nickel layer is a NiP compound. The ductility of the tin enables a tin-coated base metal sheet to be formed into a variety of shapes without damage to the surface tin layer. It provides sacrificial protection for the aluminum busbar.

    [0024] In one embodiment, the plating process 38 includes rinsing the busbar. Next, the busbar is subjected to a zinc plating step. In one embodiment, the zinc plating solution includes an alzincate EN solution having a pH greater than 12 at a temperature of 21 °C to 46 °C for 15 to 120 seconds. The busbar is rinsed again, and then subjected to stripping step, which includes stripping the busbar within a nitric acid (HNO3) bath having a solution concentration of 50 % with a pH approximately 1 at a temperature of 20 °C for 5 to 10 seconds. The plating process 38 further includes rinsing the busbar, and subjecting the busbar to another zinc plating step, which is the same as the zinc plating step described above.

    [0025] In one embodiment, the plating process 38 further includes rinsing the busbar again, and subjecting the busbar to a nickel plating step. The nickel plating step includes plating the busbar in a nickel bath, e.g., a Watts bath, having a 2 to 6 A/dm2 at a temperature of 46 °C to 71 °C for one to several minutes. The plating process 38 further includes rinsing the busbar again, and subjecting the busbar to a tin plating step. The tin plating step includes plating the busbar in a tin bath having a to 10 A/dm2 at a temperature of 20 °C to 30 °C for one to several minutes. And finally, the plating process 38 further includes rinsing the busbar, neutralizing the busbar, rinsing the busbar again, and subjecting the busbar to a post dip step.

    [0026] In other embodiments, as mentioned above, the PTFE layer is optional, since the anodized surfaces are capable of withstanding the plating step.

    [0027] Tin coatings, including the nickel and zinc undercoatings, are recognized coatings by the UL. The UL allows tin coated surfaces to be subjected to temperatures up to 90 °C, which enables less material usage. Also, tin coated aluminum can be joined with tin coated copper busbars without further restrictions. Also, of particular interest regarding production setup, is that tin is applied as a part of manufacturing whereas a deoxidizing gel would be applied in assembly. The difference in this is where responsibility is placed and how inspection and quality assurance procedures are setup.

    [0028] Common for anodizing and tin coating the busbar is that both properties offer good protection against corrosion and show long term stability. Embodiments of the method 10 include steps of anodizing and tin coating. It should be understood that methods of the embodiments disclosed herein may be applied to treating copper busbars, with the exception that anodizing on copper is not possible; however, the tin coating may be applied where desired.

    [0029] Referring to FIGS. 4-6, and more particularly to FIG. 4, the sealing jig includes the use of crab pliers, generally indicated at 40, which can withstand the harsh environment of steps the anodizing process 34. According to the invention, the crab pliers 40 are fabricated from hard plastic that is resistant to harsh chemicals. Crab pliers 40 are readily available at a reasonable cost. The crab pliers 40 are used to hold together the components of a sealing jig, generally indicated at 42, which is shown in FIGS. 5 and 6. As shown, the jig 42 includes a jig top 44 and a jig bottom 44. The crab pliers 40 are able to hold the jig top 44 and the jig bottom 46 together over the busbar 10. Further, the crab pliers 40, if properly sized, are capable of applying a sufficient force to ensure that the sealing will provide tightness during the anodizing process 34. With minor modifications, the crab pliers 40 can have the jig top 44 and jig bottom 46 permanently attached to them, so that the crab pliers consist of an assembly that can easily be applied onto the busbar 10. One benefit of this embodiment is that the sealing jig 42 allows the anodizing process 34 to be carried out in a wet environment. This construction ensures that the busbars are kept wet throughout the entire coating cycle.

    [0030] In one embodiment, the jig top 44 and the jig bottom 46 of the sealing jig 42 may be fabricated from solid material with good dimensional stability. Also, material used to fabricate the jig top 44 and the jig bottom 46 must be able to withstand the conditions (pH and temperature) applied to the busbar 10 during the anodizing process 34. According to the invention, the jig top 44 and the jig bottom are fabricated from hard plastic that is resistant to harsh chemicals. The sealing jig 42 further includes an anode 48 for the anodizing process 34. As shown, the anode 48 extends through the jig bottom 46 so that an end or tip 50 of the anode is exposed on an upwardly facing surface 52 of the jig bottom. The current required for the anodizing process 34 can be built into the sealing jig 42 as well. The crab pliers 40 may provide a force sufficient to ensure good electrical contact between the tip 50 of the anode 48 and busbar 10. The anode 48 is likely to be made of titanium or other precious materials.

    [0031] The sealing jig 42 further includes a directional pin 54, which is provided to ensure that orientation of the sealing jig is correct. As shown, the directional pin 54 extends from the upwardly facing surface 52 of the jig bottom 46. This arrangement ensures that the jig top 44 and jig bottom 46 are not reversed in error. An opening 56 is formed in the busbar 10 for the directional pin 54. After the sealing jig 42 is removed, the opening 56 can be used to receive the nickel and tin coating anodes that are used in the plating process 38. The opening 56 serves no other purpose on the finished busbar. The sealing jig 42 further includes a seal 58 provided on a downwardly facing surface 60 of the jig top 44 and several seals, each indicated at 62, which can be used to seal the anode 48 and the directional pin 54 with respect to the jig bottom 46. The seals 58, 62 can be fabricated from PTFE material, is commonly used for sealing and is able to withstand pH and temperature requirements. Other alternatives exist.

    [0032] One disadvantage associated with sealing jig 42 is that the anode 48 for anodizing process 34 may be coated with the non-conductive PTFE. This may not be desirable since the PTFE material may prevent the anode 48 from being continuously reused. To prevent the anode 48 from being coated, the anode may be integrated into the jig top 44 in a way so the seal for the jig bottom 46 offers the required protection. As shown, the anode 48 is exposed. However, this issue is easily solved by integrating the anode 48 with the jig top 44.

    [0033] FIG. 7 illustrates two alternative embodiments to the method 30 shown and described with respect to FIG. 3. In one embodiment, a method, generally indicated at 70, includes a pre-conditioning process generally indicated at 72, an anodizing process generally indicated at 74, and a plating process generally indicated at 76. As shown, the pre-conditioning process 72 is identical to the pre-conditioning process 32 shown in FIG. 3 with respect to method 30.

    [0034] Next, the busbar is treated by the anodizing process 74. As shown, the busbar is not held in place by the sealing jig. The anodizing process 74 includes de-smutting the busbar with an acid solution having a pH value less than 1. In certain embodiments, the acid solution is nitric acid (HNO3) having a solution concentration of approximately 50 %.

    [0035] After rinsing the busbar, the busbar is subjected to the plating process 76. In one embodiment, the plating process 76 includes a zinc plating step. The zinc plating solution includes an alzincate EN solution having a pH greater than 12 at a temperature of 21 °C to 46 °C for 15 to 120 seconds. The busbar is rinsed again, and then subjected to stripping step, which includes stripping the busbar within a nitric acid (HNO3) bath having a solution concentration of 50 % with a pH approximately 1 at a temperature of 20 °C for 5 to 10 seconds. The plating process 76 further includes rinsing the busbar, and subjecting the busbar to another zinc plating step, which is the same as the zinc plating step described above.

    [0036] After applying the zinc coatings, the busbar is rinsed and then held in place by the sealing jig. After another rinse and de-smutting steps, the busbar is rinsed and then subjected to an anodizing agent having a pH of approximately 1 at 20 °C at a current of 1.2 to 2 A/dm2 for one or more minutes. In certain embodiments, the anodizing agent is sulfuric acid (H2SO4) having a solution concentration of approximately 20 %. The plating process 76 further includes rinsing the busbar with an appropriate solution, and coloring the busbar with a water/dye solution having a pH between 7 and 8 at 20 °C. The plating process 76 further includes rinsing the busbar with an appropriate solution, sealing the busbar with water having a pH between 7 and 8 at a temperature of 80 °C to 95 °C, and performing a final rinsing step on the busbar. After sealing and rinsing, the busbar is dipped in paint or a silane solution having a pH of approximately 3. Next, the busbar is rinsed and removed from the sealing jig.

    [0037] The plating process 76 further includes rinsing the busbar again, and subjecting the busbar to a nickel plating step. When employed, the nickel plating step of the plating process 76 includes plating the busbar in a nickel bath, e.g., a Watts bath, having a 2 to 6 A/dm2 at a temperature of 46 °C to 71 °C for one to several minutes. The plating process 76 further includes rinsing the busbar again, and subjecting the busbar to a tin plating step. The tin plating step includes plating the busbar in a tin bath having a to 10 A/dm2 at a temperature of 20 °C to 30 °C for one to several minutes. And finally, the plating process 76 further includes rinsing the busbar, neutralizing the busbar, rinsing the busbar again, and subjecting the busbar to a post dip step.

    [0038] FIG. 7 illustrates another method, generally indicated at 80, which includes a pre-conditioning process generally indicated at 82, an anodizing process generally indicated at 84, and an optional plating process generally indicated at 86. As shown, the pre-conditioning process 82 is identical to the pre-conditioning processes 32, 72 described with respect to methods 30, 70, respectively. After the pre-conditioning process 82, the busbar is the treated by the anodizing process 84. The anodizing process 84 includes de-smutting the busbar with an acid solution having a pH value less than 1. In certain embodiments, the acid solution is nitric acid (HNO3) having a solution concentration of approximately 50 %. Next, the busbar is rinsed.

    [0039] After rinsing the busbar, the busbar is held in place by the sealing jig. After another rinsing step, the busbar is dipped in paint or a silane solution having a pH of approximately 3. Next, the busbar is rinsed and removed from the sealing jig. When employed, the plating process 86 includes rinsing the busbar again, and subjecting the busbar to a nickel plating step. The nickel plating step includes plating the busbar in a nickel bath, e.g., a Watts bath, having a 2 to 6 A/dm2 at a temperature of 46 °C to 71 °C for one to several minutes. The optional plating process 86 further includes rinsing the busbar again, and subjecting the busbar to a tin plating step. The tin plating step includes plating the busbar in a tin bath having a to 10 A/dm2 at a temperature of 20 °C to 30 °C for one to several minutes. And finally, the optional plating process 86 further includes rinsing the busbar, neutralizing the busbar, rinsing the busbar again, and subjecting the busbar to a post dip step.

    [0040] It should be observed that methods of treating busbars disclosed herein involve tin, which is an acceptable metal that is used in the UPS industry. In the methods, the coating is applied only to conducting surfaces. Therefore, less waste of coating products may be achieved. Moreover, when compared to prior full coating processes, the methods disclosed herein exhibit the ability to reduce space usage (more compact products) and higher design freedom since busbars can be placed closer to each others. Arch flash events tend to propagate, so one flash can start new flashes that lead to severe damage inside a cabinet. Non-conducting surfaces may significantly limit how an arch flash can propagate, which in turn will provide reduced warranty cost. Short circuits also may be prevented from propagating because busbars can deflect and touch each other without consequence (formation of a new short circuit). If the coating peels off or whiskers are formed, then free particles of conducting material may flow freely inside the cabinet. By applying the coating only on surfaces where strictly needed, the amount of free particles that are formed can be eliminated or significantly reduced.

    [0041] Having thus described several aspects of at least one embodiment of this disclosure, it is to be appreciated that various alterations, modifications, and improvements will readily occur to those skilled in the art, within the scope as defined by the appended claims. Accordingly, the foregoing description and drawings are by way of example only.


    Claims

    1. An apparatus comprising a busbar and a fixture used to secure the busbar for a treatment process, the fixture comprising:

    a jig top configured to engage a top surface of the busbar;

    a jig bottom configured to engage a bottom surface of the busbar; and

    crab pliers configured to apply a force on the jig top and the jig bottom to secure the busbar in place;

    said fixture being configured to perform within a wet environment so that the busbar is continuously wet during activation and deactivation of the treatment process;

    wherein the jig top, the jig bottom and the crab pliers are fabricated from hard plastic,

    wherein the fixture further comprises an anode for performing an anodizing process, wherein the anode extends through the jig bottom so that an end of the anode is exposed on an upwardly facing surface of the jig bottom, and

    wherein the fixture further comprises a directional pin to orient the jig in a correct position, wherein the directional pin extends from an upwardly facing surface of the jig bottom, the directional pin being received within an opening formed in the busbar.


     
    2. The fixture of claim 1, wherein the crab pliers are permanently attached to the jig top and jig bottom.
     
    3. The fixture of claim 1, further comprising a seal provided on a downwardly facing surface of the jig top and a seal provided on an upwardly facing surface of the jig bottom.
     
    4. A method of treating a surface of an aluminum busbar, the method comprising:

    pre-conditioning the surface of the busbar;

    anodizing one portion of the surface of the busbar; and

    plating another portion of the surface of the busbar with at least one metal;

    wherein anodizing one portion of the surface of the busbar includes securing the busbar in the fixture of the apparatus as claimed in any preceding claim, in order to expose the one portion of the surface of the busbar.


     
    5. The method of claim 4, wherein anodizing one portion of the surface of the busbar includes securing the busbar in the fixture, de-smutting the busbar with an acid solution, applying an anodizing agent, coloring the busbar with a water/dye solution and sealing the busbar with water.
     
    6. The method of claim 5, further comprising applying a protective layer on the one portion of the surface of the busbar.
     
    7. The method of claim 6, wherein the protective layer is fabricated from PTFE.
     
    8. The method of claim 6, wherein the fixture is removed after applying the protective layer.
     
    9. The method of claim 6, wherein the plating process includes plating the another portion of the busbar with at least one zinc coating.
     
    10. The method of claim 9, wherein the plating process further includes plating the another portion of the busbar with a nickel coating, plating the another portion of the busbar with a tin coating, neutralizing the another portion of the busbar, and subjecting the another portion of the busbar to a post dip step.
     


    Ansprüche

    1. Eine Vorrichtung, die eine Sammelschiene und eine Halterung, die zum Sichern der Sammelschiene für einen Behandlungsprozess verwendet wird, beinhaltet, wobei die Halterung Folgendes beinhaltet:

    ein Einspannvorrichtungsoberteil, das konfiguriert ist, um in eine obere Oberfläche der Sammelschiene einzugreifen;

    ein Einspannvorrichtungsunterteil, das konfiguriert ist, um in eine untere Oberfläche der Sammelschiene einzugreifen; und

    eine Greifzange, die konfiguriert ist, um eine Kraft auf das Einspannvorrichtungsoberteil und das Einspannvorrichtungsunterteil aufzubringen, um die Sammelschiene an Ort und Stelle zu sichern;

    wobei die Halterung konfiguriert ist, um in einer nassen Umgebung zu funktionieren, sodass die Sammelschiene während der Aktivierung und Deaktivierung des Behandlungsprozesses kontinuierlich nass ist;

    wobei das Einspannvorrichtungsoberteil, das Einspannvorrichtungsunterteil und die Greifzange aus hartem Kunststoff hergestellt sind,

    wobei die Halterung ferner eine Anode zum Durchführen eines Anodisierungsprozesses beinhaltet,

    wobei sich die Anode durch das Einspannvorrichtungsunterteil erstreckt, so dass ein Ende der Anode auf einer nach oben gewandten Oberfläche des Einspannvorrichtungsunterteils freiliegt, und

    wobei die Halterung ferner einen Richtstift zum Ausrichten der Einspannvorrichtung in eine korrekte Position beinhaltet, wobei sich der Richtstift aus einer nach oben gewandten Oberfläche des Einspannvorrichtungsunterteils erstreckt, wobei der Richtstift in einer in der Sammelschiene ausgebildeten Öffnung aufgenommen wird.


     
    2. Halterung gemäß Anspruch 1, wobei die Greifzange permanent an dem Einspannvorrichtungsoberteil und dem Einspannvorrichtungsunterteil befestigt ist.
     
    3. Halterung gemäß Anspruch 1, die ferner eine Dichtung, die an einer nach unten gewandten Oberfläche des Einspannvorrichtungsoberteils bereitgestellt ist, und eine Dichtung, die an einer nach oben gewandten Oberfläche des Einspannvorrichtungsunterteils bereitgestellt ist, beinhaltet.
     
    4. Ein Verfahren zum Behandeln einer Oberfläche einer Aluminiumsammelschiene, wobei das Verfahren Folgendes beinhaltet:

    Vorkonditionierung der Oberfläche der Sammelschiene;

    Anodisieren eines Abschnitts der Oberfläche der Sammelschiene; und

    Plattieren eines weiteren Abschnitts der Oberfläche der Sammelschiene mit mindestens einem Metall;

    wobei das Anodisieren eines Abschnitts der Oberfläche der Sammelschiene das Sichern der Sammelschiene in der Halterung der Vorrichtung, wie in den vorhergehenden Ansprüchen beansprucht, umfasst, um den einen Abschnitt der Oberfläche der Sammelschiene freizulegen.


     
    5. Verfahren gemäß Anspruch 4, wobei das Anodisieren eines Abschnitts der Oberfläche der Sammelschiene das Sichern der Sammelschiene in der Halterung, das Entschmutzen der Sammelschiene mit einer Säurelösung, das Aufbringen eines Anodisiermittels, das Einfärben der Sammelschiene mit einer Wasser-/Farbstofflösung und das Versiegeln der Sammelschiene mit Wasser umfasst.
     
    6. Verfahren gemäß Anspruch 5, das ferner das Aufbringen einer Schutzschicht auf dem einen Abschnitt der Oberfläche der Sammelschiene beinhaltet.
     
    7. Verfahren gemäß Anspruch 6, wobei die Schutzschicht aus PTFE hergestellt wird.
     
    8. Verfahren gemäß Anspruch 6, wobei die Halterung nach dem Aufbringen der Schutzschicht entfernt wird.
     
    9. Verfahren gemäß Anspruch 6, wobei der Plattierungsprozess das Plattieren des weiteren Abschnitts der Sammelschiene mit mindestens einer Zinkbeschichtung umfasst.
     
    10. Verfahren gemäß Anspruch 9, wobei der Plattierungsprozess ferner Folgendes umfasst: das Plattieren des weiteren Abschnitts der Sammelschiene mit einer Nickelbeschichtung, das Plattieren des weiteren Abschnitts der Sammelschiene mit einer Zinnbeschichtung, das Neutralisieren des weiteren Abschnitts der Sammelschiene und das Unterziehen des weiteren Abschnitts der Sammelschiene einem Tauchschritt danach.
     


    Revendications

    1. Un appareil comprenant une barre omnibus et un accessoire utilisé afin d'assujettir la barre omnibus pour un processus de traitement, l'accessoire comprenant :

    un dessus de gabarit de montage configuré pour se mettre en prise avec une surface de dessus de la barre omnibus ;

    un dessous de gabarit de montage configuré pour se mettre en prise avec une surface de dessous de la barre omnibus ; et

    une pince-crabe configurée pour appliquer une force sur le dessus de gabarit de montage et le dessous de gabarit de montage afin d'assujettir la barre omnibus en place ;

    ledit accessoire étant configuré pour fonctionner dans un milieu mouillé de sorte que la barre omnibus soit continuellement mouillée durant l'activation et la désactivation du procédé de traitement ;

    dans lequel le dessus de gabarit de montage, le dessous de gabarit de montage et la pince-crabe sont fabriqués à partir de plastique dur,

    dans lequel l'accessoire comprend en outre une anode pour l'exécution d'un procédé d'anodisation,

    dans lequel l'anode s'étend à travers le dessous de gabarit de montage de sorte qu'une extrémité de l'anode est exposée sur une surface tournée vers le haut du dessous de gabarit de montage, et

    dans lequel l'accessoire comprend en outre un tourillon directionnel afin d'orienter le gabarit de montage dans une position correcte, dans lequel le tourillon directionnel s'étend à partir d'une surface tournée vers le haut du dessous de gabarit de montage, le tourillon directionnel étant reçu au sein d'une ouverture pratiquée dans la barre omnibus.


     
    2. L'accessoire de la revendication 1, dans lequel la pince-crabe est attachée de façon permanente au dessus de gabarit de montage et au dessous de gabarit de montage.
     
    3. L'accessoire de la revendication 1, comprenant en outre un joint prévu sur une surface tournée vers le bas du dessus de gabarit de montage et un joint prévu sur une surface tournée vers le haut du dessous de gabarit de montage.
     
    4. Un procédé de traitement d'une surface d'une barre omnibus en aluminium, le procédé comprenant :

    le pré-conditionnement de la surface de la barre omnibus ;

    l'anodisation d'une portion de la surface de la barre omnibus ; et

    le placage d'une autre portion de la surface de la barre omnibus avec au moins un métal ;

    dans lequel l'anodisation d'une portion de la surface de la barre omnibus inclut l'assujettissement de la barre omnibus dans l'accessoire de l'appareil tel que revendiqué dans n'importe quelle revendication précédente, afin d'exposer cette une portion de la surface de la barre omnibus.


     
    5. Le procédé de la revendication 4, dans lequel l'anodisation d'une portion de la surface de la barre omnibus inclut l'assujettissement de la barre omnibus dans l'accessoire, l'élimination du dépôt sur la barre omnibus à l'aide d'une solution acide, l'application d'un agent anodisant, la coloration de la barre omnibus à l'aide d'une solution d'eau/de teinture et le colmatage de la barre omnibus avec de l'eau.
     
    6. Le procédé de la revendication 5, comprenant en outre l'application d'une couche protectrice sur cette une portion de la surface de la barre omnibus.
     
    7. Le procédé de la revendication 6, dans lequel la couche protectrice est fabriquée en PTFE.
     
    8. Le procédé de la revendication 6, dans lequel l'accessoire est retiré après l'application de la couche protectrice.
     
    9. Le procédé de la revendication 6, dans lequel le processus de placage inclut le placage de cette autre portion de la barre omnibus avec au moins un revêtement de zinc.
     
    10. Le procédé de la revendication 9, dans lequel le processus de placage inclut en outre le placage de cette autre portion de la barre omnibus avec un revêtement de nickel, le placage de cette autre portion de la barre omnibus avec un revêtement d'étain, la neutralisation de cette autre portion de la barre omnibus, et la soumission de cette autre portion de la barre omnibus à une étape de post-trempage.
     




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    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description