Selector switch for tap-changing transformers and support arm for a tap selector thereof

Patent metadata

Field	Value
Publication number	US-2016133399-A1
Application number	US-201414898498-A
Country	US
Kind code	A1
Filing date	Jun 24, 2014
Priority date	Jul 16, 2013
Publication date	May 12, 2016
Grant date	—

Abstract

The invention relates to a selector switch ( 1 ) for tap-changing transformers. The selector switch ( 1 ) has a tap selector ( 37 ) in the oil tank ( 18 ) of said selector switch ( 1 ). In accordance with the invention, two separate zero contacts ( 73, 74 ) belong to each phase (L 1, L 2, L 3 ) to be switched by the tap selector ( 37 ). The zero contacts ( 73, 74 ) are each arranged on a wall ( 17 ) of the oil tank ( 18 ) and reach through the wall ( 17 ). The invention also relates to a support arm ( 62 ) of a tap selector ( 37 ) of a selector switch ( 1 ). The support arm ( 62 ) has a first lateral rib ( 65 ) and a second lateral rib ( 66 ) and at least one web-like elevation ( 67 ) extending along a length (L) of the support arm ( 62 ) is formed between the first lateral rib ( 65 ) and the second lateral rib ( 66 ).

First claim

1 . A load selector for tapped transformers, the load selector comprising:
an oil tank; and a preselector having a first preselector contact and a second preselector contact for each phase to be switched by the load selector the first preselector contact and the second preselector contact being mounted on a wall of the oil tank and extending through the wall of the oil tank; and a first zero contact and a second zero contact separate from the first zero contact for each phase to be switched by the preselector the first zero contact and the second zero contact each being mounted on the wall of the oil tank and extending through the wall of the oil tank.

2 . The load selector according to claim 1 , wherein, for at least one phase to be switched by the load selector, the first zero contact and the second zero contact are electrically conductively connected outside the oil tank by a respective connecting element.

3 . The load selector according to claim 1 , wherein, in a first switching state of the preselector, an electrically conductive connection is provided within the oil tank between the first preselector contact and the first zero contact and, in a second switching state of the preselector, an electrically conductive connection is provided within the oil tank between the second preselector contact and the second zero contact.

4 . The load selector according to claim 3 , wherein
the preselector comprises a contact support inside the oil tank and having an electrically conductive contact bridge for each phase to be switched by the load selector and rotatable relative to the oil tank between a first contact setting and a second contact setting, in the first contact setting of the contact support the first switching state of the preselector is realized and in that case for each phase to be switched by the load selector a first end of the respective contact bridge is in electrically conductive connection with the respective first preselector contact and a second end of the contact bridge contacts the respective first zero contact, and in the second contact setting of the contact support the second switching state of the preselector is realized and in that case the first end of the respective contact bridge is in electrically conductive connection with the respective second preselector contact and the second end of the contact bridge contacts the respective second zero contact.

5 . The load selector according to claim 4 , wherein the contact support comprises a support ring at which as many support arms are provided as phases to be switched by the load selector and one of the contact bridges is mounted on an end of a respective support arm opposite the support ring.

6 . The load selector according to claim 5 , wherein the contact bridges are arranged along the circumference of a circle having a diameter greater than an outer diameter of the support ring.

7 . The load selector according to claim 1 wherein the load selector has three phases.

8 . A support arm of a preselector of a load selector with a mounting section and a free end that is formed opposite the mounting section and at which a fastening position for a contact bridge is provided, wherein the support arm is formed with a first lateral rib, a second lateral rib and between the first lateral rib and the second later rib at least one web-like elevation extending along a full length of the support arm.

9 . The support arm according to claim 8 , wherein the fastening position for the contact bridge is formed by the web-like elevation at the free end of the support arm, and in addition a first lateral mount and a second lateral mount for the contact bridge are formed at the free end of the support arm.

10 . The support arm according to claim 8 , wherein the support arm is formed with a plurality of area elements that are each arranged at an angle relative to one another and that extend from the mounting section toward the free end of the support arm.

11 . The support arm according to claim 10 , wherein the support arm together with the plurality of area elements, the first lateral rib, the second lateral rib, the web-like elevation, the fastening position, the first lateral mount and the second lateral mount is injection-molded from an electrically nonconductive material.

12 . The support arm according to claim 12 , wherein the electrically nonconductive material is a plastic.

Assignees

• Reinhausen Maschf Scheubeck

Inventors

• Zwirglmaier Hubert
• Wrede Silke
• Schuster Thomas
• Laubereau Ulli
• Baeuml Gerhard

Classifications

• H01H9/0016

  Contact arrangements for tap changers · CPC title

• H01H9/0027 Primary

  Operating mechanisms · CPC title

• H01H2009/0022

  Mounting of the fixed contacts or taps on cylindrical wall of oil vessel containing the tap changer; Details of screening · CPC title