US3448422A - Housing construction for multiple tap transformer - Google Patents
Housing construction for multiple tap transformer Download PDFInfo
- Publication number
- US3448422A US3448422A US503871A US3448422DA US3448422A US 3448422 A US3448422 A US 3448422A US 503871 A US503871 A US 503871A US 3448422D A US3448422D A US 3448422DA US 3448422 A US3448422 A US 3448422A
- Authority
- US
- United States
- Prior art keywords
- tank
- transformer
- shell
- regulating device
- aperture
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000010276 construction Methods 0.000 title description 28
- 239000004020 conductor Substances 0.000 description 44
- 230000001105 regulatory effect Effects 0.000 description 44
- 238000004804 winding Methods 0.000 description 15
- 238000005192 partition Methods 0.000 description 8
- 238000009413 insulation Methods 0.000 description 4
- 238000012423 maintenance Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/40—Structural association with built-in electric component, e.g. fuse
Definitions
- the present invention relates in general to transformers having multiple taps or connections connected to a live regulating or switching device for selecting various coil combinations.
- the live regulating device may be of any desired type and may comprise, for example, a tap preselector and a live switch for the taps chosen by the preselector.
- the present invention is concerned, more particularly, with transformers comprising a regulating device to which a voltage is directly applied disposed at the outside of the principal tank enclosing the transformer, including the magnetic circuit and windings, the tank being filled with oil in the conventional manner.
- the regulating device utilized with transformers of the type described comprises generally a live switch whose operation is known to result in a pollution of the oil in which it is immersed and thus it is important to prevent any sizable or significant quantity of polluted oil from penetrating through to the active part of the transformer.
- One of the solutions previously proposed consists of creating a fluid-tight insulating wall between the tank containing the regulating device and the tank containing the transformer.
- Another solution comprises accommodating each of the two elements in one of two distinct compartments of the housing separated by means of a wall positioned at the inside of the tank, this wall being provided with an aperture disposed at the lower part thereof so as to allow for the passage of the necessary connections from the transformer to the regulator while limiting as much as possible the interchange of oil therebetween.
- the live regulating device comprises movable mechanical elements which are constantly subjected to wear, and include conductive or insulating elements which may have to be replaced from time to time, and so it is of importance that a ready access be provided thereto without having to disassemble the entire unit of the transformer or to drain off the oil, necessitating a refilling of the active part of this transformer each time.
- the maintenance of the transformer itself necessitates the removal of the principal tank or removal of the transformer from the tank, which should be carried out with a minimum of disassembling or disturbance to the live regulating device.
- the present invention has the object of providing a unitary transformer including a live regulating device which avoids the inconveniences of the heretofore known units and which proposes a solution for the problems mentioned hereinbefore.
- the transformer having multiple taps with a regulating device therefor is characterized by a construction wherein the transformer is immersed into a main tank having a lateral wall including an aperture which is enclosed by first and second elementary shells, positioned respectively at the outside and at the inside of said tank and secured with the edges thereof on the tank, surrounding said aperture, for the purpose of forming an envelope or enclosure, wherein the regulating device is immersed in oil, which device is connected to said multiple taps by connecting conductors passing through a wall of the elementary shell positioned at the inside of the tank.
- the present invention makes it possible to accommodate the regulating device at the outside of the tank of the transformer with minimum increase in size of the overall transformer construction and without the secondary elementary shell positioned at the inside of the tank of the transformer markedly reducing the free space therein.
- the small cavity or pocket formed at the outer surface fo the tank of the transformer by the second elementary shell makes it possible to accommodate therein the part of the connecting conductors which emerge from the tank of the transformer which are exposed when the regulating device is disassembled. This small cavity or pocket may then be closed in a fluid-tight manner by a simple partition and filled with oil. It is thus possible to provide each of the connecting conductors of uniform length .and to maintain the insulation thereof impregnated with oil, without having to fear that the insulation might lose the impregnating oil thereof after the regulating device has been disassembled.
- the part of the wall of the second shell which is traversed by the connecting conductors is. oriented in such a manner as to be perpendicular to these conductors at the points where they pass through the wall, these conductors being thus disposed so as to reduce the number Patented June 3, 1969 of bends and turns therein along their path.
- This last disposition makes it possible to avoid the supplementary bends or curves in the conductors which would be necessary for mounting the lead-through elements perpendicularly to the lateral wall of the tank of the transformer. It is thus possible to reduce the length of the connecting conductors and, consequently, the total overall dimensions of the transformer assembly.
- said second elementary shell positioned at the inside of the tank of the transformer, -is mounted thereon with fastening means rendering this second shell essentially integral with the magnetic circuit of the transformer and of its windings, independently of the lateral wall of the tank.
- the transformer may be removed from the tank with the connecting conductors after the disassembly of the regulating device and of the fastening means between said second shell and the lateral wall of the tank of the transformer.
- the part of the connecting conductors which is positioned at the'outside of the tank of the transformer will then be accommodated in the small cavity or pocket formed by the second elementary shell and will no longer oppose the removal of the transformer from the tank.
- the second elementary shell which is positioned in the tank of the transformer comprises a wall made of an insulating material, at least in the part thereof which is traversed by said connecting conductors.
- the leadthrough of the connecting conductors may particularly be constituted by simple bushings, or insulated connectors through an aperture sufficiently fluid-tight to avoid an exchange or interchange of oil, which would result in a detrimental pollution of the transformer oil.
- the lead-through of the conductors may equally be positioned at the lower part of the enclosure or envelope formed by the first and the second elementary shells making it possible to provide said lead-throughs without any fluid-tightness, while at the same time allowing for the possibility of partially draining off the oil contained in the first and the second elementary shells to the level of these lead-throughs, the tank of the transformer then being provided, above this level, with closing means making it possible to render the tank fluid-tight during the partial drainage of the envelope or enclosure formed by the first and second shells.
- FIGURE 1 is a sectional view partially schematic of a triphase multiple tap transformer having a regulating device associated therewith in accordance with the invention, taken along line A-A' of FIGURE 2;
- FIGURE 2 is a transverse cross-sectional view taken along line B-B' of FIGURE 1, and
- FIGURE 3 is a 'view similar to that of FIGURE 1 of a modification of the triphase multiple'tap transformer having a regulating device associated therewith in accordance with the invention.
- transformers whose active part comprises a magnetic circuit upon which are mounted three windings 1, 2 and 3 for the three phases and having multiple taps associated therewith.
- the active part of the transformer illustrated in FIGURES 1 and 2 is immersed into a tank which comprises an envelope 8 having a bell shape, or any other conventional configuration, secured with the lower part thereof, by means of a flange joint 9, to a base plate 7 in the form of a shallow receptacle upon which the active part of the transformer is mounted.
- one of the side walls of the tank 8 is provided with a rectangular aperture 51.
- first elementary shell 52 is positioned at the outside of the tank so as to enclose the aperture 51 and is secured to the wall of the tank 8 around the edges of the aperture.
- This attachment is effected by means of an L-shaped frame 53, or other suitable securing means, which is soldered to the wall of the tank 8 around the aperture 51.
- the frame 53 and the elementary shell 52 provide opposing surfaces which form a flange joint 54, tightened by means of bolts or other securing devices (not shown) so that this attachment allows for an easy and rapid assembly and disassembly of the elementary enclosure 52.
- a second elementary shell 55 is positioned at the inside of the tank and surrounds the aperture 51 with inwardly turned edges so as to form a flange joint 56 by means of which the shell 55 is attached to the side wall of the tank 8 around the edges of the aperture 51.
- the two elementary shells 52 and 55 constitute an envelope or enclosure into which is immersed a regulating device 13 which may include, for example, a live switch.
- the regulating device may be immersed directly into the oil in the space formed by the shells 52 and 55; however, in most cases, at least a part of the regulating device, for example the live switch, is placed into a separate fluidtight tank which is provided with oil by an expansion vessel 28 forming part of a reservoir 27.
- the device 13 may also include a connecting box 14 for the conductors connected to the taps, which connecting box may be coaxial with the live switch 13.
- the oil reservoir 27 includes a partial internal partition 33 defining two compartments 28 and 28; the compartment 28" is connected by means of a gas-detecting relay 39 to two conduits 35 and 36 connected respectively to the regulating valves 37 and 38, and also connected to the active part of the transformer defined by the housing 8 and the enclosure defined by the shells 52 and 55,
- the compartment 28 of the reservoir 27 is connected only to the tank surrounding the live switch 13 by means of the conduit 30 in series connection with valve 32. Due to the existence of the partition 33 providng a separation of the supply circuits, the oil contained 1n the tank of the live switch cannot be mixed with the contaminated oil contained in the space between the shells 52 and 55 and in the active part of the transformer.
- the connection between the terminals of the connecting box 14 and the different multipletaps or connections of the windings 1, 2 and 3 is obtained by means of the strips of conductors 4, 5 and 6, respectively. They penetrate or extend into the elementary shell 55 through an insulating bushing which is secured in a fluid-tight manner within an aperture in one of the walls of the shell 55. In spite of the illustrated construction in the FIGURES, it is obviously not necessary that the conductor strips 4, 5 and 6 be superimposed and positioned directly upon each other at the inside of the tank.
- the elementary shell 55 may :be so provided and arranged that the insulating bushing 23 thereof is positioned and oriented so as to facilitate the provision of the connecting conductors over their path or course between the multiple taps and the regulating device.
- the elementary shell 55 may, moreover, comprise several insulating bushings 23, for example one for each connecting conductor, and these different insulating bushings 23 may be oriented differently so as to facilitate the provision of these connecting conductors. It is thus possible to reduce the curves and bends in the connecting conductors. This makes it possible to particularly reduce the length of the connecting conductors and to increase the space which is left free within the housing.
- the provision of the shells 52 and 55 according to the above-described construction aids in reducing the dimensions of the tank which, according to the provision and arrangement described herein, contains only the active part of the transformer without the presence of the shell 55 substantially effecting the space which is left free.
- the regulating device is thereby positioned at the outside of the tank without the total overall dimensions thereof being considerably increased.
- One of the principal advantages of the construction in accordance with the invention resides in the capability for complete disassembly of the regulating device without making it necessary to drain olf the main transformer tank, even partially. It is suflicient to disassemble the flange joint 54 by means of which the elementary shell 52 is attached to the side wall of the tank and to disassemble the connections to the connecting box :14 of the regulating device. The elementary shell 55 then forms a small cavity or pocket opening out from the side wall of the tank of the transformer. The exposed extremities of the connecting conductors which emerge from the tank through the insulating bushing 23 may thus be accommodated in this small cavity or pocket and may be enclosed therein by closing the same by means of a simple partition attached to the edges of the frame 53 soldered on the tank.
- Each of the connecting conductors may thus be provided of a single length extending through the insulating bushing 23.
- This conductor may be provided over the entire length thereof with an oil-impregnated insulation and due to the ability to enclose the conductors during removal of the regulating device, there is no need to fear that this insulation 'will lose its impregnating oil after the disassembly of the regulating device.
- the small cavity or pocket formed by the elementary shell 55 may, in fact, be filled with oil after having been closed off, as has been stated hereinbefore.
- the active part including the windings and magnetic cores of the transformer may be removed from the tank 'without making it necessary to disassemble the connection between the connecting conductors 4, and 6 and the multiple taps of the windings (not shown).
- the elementary shell 55 is provided as an integral part of the active portion of the transformer.
- a first fastening means schematically illustrated as a rod 57, connects the magnetic circuit to a lug portion 58 which is secured to the upper part of the elementary shell -55.
- the lower wall of the shell 55 is in turn secured to a support 59 by means of suitable lug portions (not visible in the drawing) which are, in turn, secured to the base plate 7.
- the construction in accordance with the invention makes it possible to proceed with the removal from the tank of the active part of the trans former by accommodating in the shell 55 the extremities of the connecting conductors which emerge from the insulating bushing 23 toward the regulating device.
- the free extremities of the connecting conductors which emerge or issue from the insulating bushing 23 are then bent into the small cavity or pocket formed by the elementary shell 55 and the removal from the tank of the active part may then be carried out without difliculty by withdrawing the transformer and shell 55 as a unit.
- the passages of the connecting conductors from the tank 8 to the envelope or enclosure defined by the shells 52 and 5-5 surrounding the regulating device do not require high-voltage lead-through bushings. It suffices to assure the fluid-tightness of the passage through the insulating partition 23 by means of simple packing, insulating boxes or any other fluid-tight means. In addition, it is not always necessary that this fluid-tightness be absolute and strict. It may sufiice that the oil exchanges between the two envelopes or enclosures be slow enough to involve only small quantities over a period of time. The disassembly of the regulating device no longer requires a strict and absolute fluid-tightness of the passage of the conductors through the bushing 23-. It suffices to limit the oil loss which may be produced during the disassembly until the small cavity or pocket formed by the shell 5'5 is closed off.
- the passage of the connecting conductors from one enclosure to the other may even be effected without any fluid-tight means for the conductors by means of a simple aperture through the elementary shell properly positioned at the inside of the tank of the transformer.
- the active part of the transformer comprises a magnetic circuit upon which are mounted three windings l1, 2 and 3 for a three phase voltage.
- a tank 8 encloses this active part and is secured by means of a flange joint 9 to a base plate 7 in the form of a shallow receptacle.
- a side wall of the tank 8 includes a rectangular aperture '51 as in the embodiment of FIG- URES 1 and 2.
- a shell positioned at the inside of the tank 8 surrounds the aperture 51 and is secured to the wall of the tank around the aperture by means of a flange joint 56.
- This shell 1155 does not comprise an insulating bushing but is provided only 'with a simple aperture 123 which is positioned at the lower part of the shell and through which extend-without fluid-tight meansthe connecting conductors being grouped together into a strip or bundle 124-.
- the shell 1'52 is constituted of two parts having a removable cover or lid. These two parts are assembled by means of a flange joint 163 positioned in an oblique plane determined so that, after the disassembly or removal of the cover, the inner part of the shell is accessible through an aperture whose lowest point is at a level higher than the highest point of the aperture bushing 123 through the shell 155.
- the regulating device 13' is enclosed in an envelope formed by the two shells 152 and 155.
- a reservoir 27 is connected similarly to this envelope and to the tank -8 by a gas relay 39, tubulures .3 5 and 36, and gates 37 and 38.
- One compartment 28 of the reservoir formed by the partition 30 is connected to a tank of the live switch.
- a housing for multitap transformer construction having an active portion including a plurality of windings and magnetic cores for said windings and a regulating device for controlling the connection to said windings, said housing comprising:
- a first closed tank enclosing the active portion of said transformer construction including a base element directly supporting said active portion and an upper element having side walls surrounding said active portion substantially along the entire height thereof,
- a second closed tank comprising inner and outer shells releasably secured to opposite sides of a lateral wall of said upper element in face-to-face relationship
- said lateral wall being provided with an aperture effecting communication between the spaces defined by said shells,
- said regulating device being mounted within said second closed tank, said first and second tanks being substantially filled with oil, and
- a housing for a multitap transformer construction as defined in claim 1 further including first fastening means for interconnecting said active portion of said transformer to said inner shell and second fastening means releasably securing said inner shell to said upper element.
- a housing for multitap transformer construction as defined in claim 1 further including insulating leadthrough bushing means secured to a wall of said inner shell, said conductor means passing through said bushing means and being hermetically sealed thereto.
- a housing for a multitap transformer construction as defined in claim 1 further including an aperture disposed in the lower portion of a wall of said inner shell for accommodating the passage of said conductor means from said first tank to said second tank, and removable cover means disposed in the upper part of said outer shell with the lowest point thereof positioned at slightly above the highest portion of said aperture in said inner shell.
- a housing for a multitap transformer construction as defined in claim 1 further including a third tank enclosing said regulating device and supported within said second tank, said third tank being filled with oil and including hermetically sealed passage for passing said conductor means through said tank.
- a housing for multitap transformer construction as defined in claim 7 further including oil reservoir means for supplying oil to said first, second and third tanks including first and second isolated compartments containing oil, first valve means connecting said first compartment only to said third tank and second valve means connecting said second compartment only to said first and second tanks.
- a multitap transformer construction having an active portion including a plurality of windings with taps and magnetic cores for said windings and a regulating device for controlling the application of voltage to said taps, the improvement substantially consisting of a housing for said transformer construction, comprising:
- said second tank comprises inner and outer shells releasably secured to opposite sides of a lateral wall of said first tank in face-toface relationship, said lateral Wall including an aperture efiecting communication between the spaces defined by said shells.
- a multitap transformer construction as defined in claim 9 further including first fastening means connecting said inner shell to said active portion of said transformer and second fastening means releasably securing said inner shell to said lateral wall of said first tank.
- a multitap transformer construction as defined in claim 1 further including lead-through bushing means secured to a wall of said inner shell, said conductor means passing through said bushing means and forming a hermetic seal therewith.
- a multitap transformer construction as defined in claim 9 further including an aperture disposed in the lower portion of a wall of said inner shell for accommodating the passage of said conductor means from said first tank to said second tank, and partition means obliquely disposed in said outer shell and having an aperture therein through which said regulating device extends, said aperture in said partition means being disposed above the aperture in said inner shell.
- a multitap transformer construction as defined in claim 9 further including a third tank within said second tank and enclosing said regulating device.
- a multitap transformer construction as defined in claim 13 including first and second sources of oil, said first source of oil being connected only to said third tank and said second source of oil being connected only to said first and second tanks.
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Housings And Mounting Of Transformers (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR998515A FR91616E (fr) | 1964-12-14 | 1964-12-14 | Transformateurs à prises multiples avec dispositif de réglage |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3448422A true US3448422A (en) | 1969-06-03 |
Family
ID=8844725
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US503871A Expired - Lifetime US3448422A (en) | 1964-12-14 | 1965-10-23 | Housing construction for multiple tap transformer |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US3448422A (enExample) |
| BE (1) | BE673442A (enExample) |
| DE (1) | DE1488824A1 (enExample) |
| ES (1) | ES318674A1 (enExample) |
| FR (1) | FR91616E (enExample) |
| GB (1) | GB1118199A (enExample) |
| NL (1) | NL6516237A (enExample) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3621426A (en) * | 1970-11-12 | 1971-11-16 | Westinghouse Electric Corp | Transformer with bushing compartment |
| US4205289A (en) * | 1978-04-25 | 1980-05-27 | Electric Power Research Institute, Inc. | Vaporization cooled electrical inductive apparatus |
| US4500935A (en) * | 1981-09-02 | 1985-02-19 | Mitsubishi Denki Kabushiki Kaisha | Package substation in tank with separate chambers |
| US20140035710A1 (en) * | 2011-04-07 | 2014-02-06 | Abb Technology Ag | Fluid insulated high voltage coil |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1940311A (en) * | 1931-12-24 | 1933-12-19 | Gen Electric | Transformer casing |
| US2541236A (en) * | 1948-06-08 | 1951-02-13 | Comb Control Corp | Electrode mounting device |
| GB813464A (en) * | 1956-07-18 | 1959-05-13 | British Thomson Houston Co Ltd | Improvements relating to arrangements including electrically insulating bushing assemblies |
| US2915720A (en) * | 1954-01-13 | 1959-12-01 | Elin Union Ag Fur Elek Sche In | Transformer with a bell-shaped cover and an on-load-tap-changing device |
| US2960672A (en) * | 1958-05-21 | 1960-11-15 | Elin Ag Fur Elek Sche Ind | Transformer |
| US3041560A (en) * | 1960-06-21 | 1962-06-26 | Allis Chalmers Mfg Co | Distribution voltage regulator |
-
0
- BE BE673442D patent/BE673442A/xx unknown
-
1964
- 1964-12-14 FR FR998515A patent/FR91616E/fr not_active Expired
-
1965
- 1965-10-19 ES ES0318674A patent/ES318674A1/es not_active Expired
- 1965-10-23 US US503871A patent/US3448422A/en not_active Expired - Lifetime
- 1965-11-18 GB GB49122/65A patent/GB1118199A/en not_active Expired
- 1965-12-10 DE DE19651488824 patent/DE1488824A1/de active Pending
- 1965-12-14 NL NL6516237A patent/NL6516237A/xx unknown
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1940311A (en) * | 1931-12-24 | 1933-12-19 | Gen Electric | Transformer casing |
| US2541236A (en) * | 1948-06-08 | 1951-02-13 | Comb Control Corp | Electrode mounting device |
| US2915720A (en) * | 1954-01-13 | 1959-12-01 | Elin Union Ag Fur Elek Sche In | Transformer with a bell-shaped cover and an on-load-tap-changing device |
| GB813464A (en) * | 1956-07-18 | 1959-05-13 | British Thomson Houston Co Ltd | Improvements relating to arrangements including electrically insulating bushing assemblies |
| US2960672A (en) * | 1958-05-21 | 1960-11-15 | Elin Ag Fur Elek Sche Ind | Transformer |
| US3041560A (en) * | 1960-06-21 | 1962-06-26 | Allis Chalmers Mfg Co | Distribution voltage regulator |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3621426A (en) * | 1970-11-12 | 1971-11-16 | Westinghouse Electric Corp | Transformer with bushing compartment |
| US4205289A (en) * | 1978-04-25 | 1980-05-27 | Electric Power Research Institute, Inc. | Vaporization cooled electrical inductive apparatus |
| US4500935A (en) * | 1981-09-02 | 1985-02-19 | Mitsubishi Denki Kabushiki Kaisha | Package substation in tank with separate chambers |
| US20140035710A1 (en) * | 2011-04-07 | 2014-02-06 | Abb Technology Ag | Fluid insulated high voltage coil |
| US9058926B2 (en) * | 2011-04-07 | 2015-06-16 | Abb Technology Ag | Fluid insulated high voltage coil |
Also Published As
| Publication number | Publication date |
|---|---|
| BE673442A (enExample) | |
| NL6516237A (enExample) | 1966-06-15 |
| GB1118199A (en) | 1968-06-26 |
| ES318674A1 (es) | 1966-05-16 |
| DE1488824A1 (de) | 1969-04-10 |
| FR91616E (fr) | 1968-07-19 |
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