DE2620211B2 - Pre-selection for step switches of adjustable transformers - Google Patents

Description

The invention relates to a counter accordingly the features in the preamble of claim 1.

Such a selection is known from the German patent application 12 90 252. Here are additional to the main contacts connected to the winding ends damping contacts are provided, which are connected via resistors are connected to the respective adjacent main contact. The fixed contacts of there described reversing switch are spatially arranged on an η circular arc and each on an insulating rod attached.

Movable contacts driven by a selector gear mechanism are provided for switching.

In addition, it is from the German interpretation book 02 871 an arrangement has become known in which the moving contact of a reversing switch several has parallel rails that connect fixed contacts with a slip ring. In each case those up first The rail running up against the fixed contact provides a connection via a resistor to the permanent main contact.

In the case of adjustable transformers with large setting ranges, the well-known damping and articulation resistances are used provided in order to prevent the fine step winding free during the switching process from having a potential to earth, which deviates significantly from the potential present when the contact is closed. This potential essentially depends on the Capacities of the fine step winding to earth and to neighboring windings and is thus of the The construction of the respective transformer is significantly influenced.

The object of the present invention is now to provide a preselector for tap changers in the preamble of Claim I to create the same uniformly using as few as possible Components can be adapted to all requirements.

According to the invention, this object is achieved by the features mentioned in the characterizing part of patent claim 1 solved Advantageous developments are described in the subclaims.

Due to the structure according to the invention a 5 such Preselect; it is possible at any time to add a selection later with damping resistors and, if necessary, to equip it with an articulation contact with an articulation resistance. For this additional insulating rods can be installed and to avoid the interruption when switching

is th of the moving contact a cross rail perpendicular to the rails of the moving contact be attached.

The invention is described below using a circuit example shown schematically. It shows

F i g. 1 an arrangement with two damping resistors and one articulation resistor,

F i g. Figure 2 is a plan view of a preselector with the various fixed contacts and the on running contact adjustable on a pitch circle path,

Fig. 3 is a snapshot of the installation of the damping resistors: in the selection.

In the arrangement according to FIG. 1 is the pivot point 1 connected to the movable contact 10 of the Pre-selector connected to the end of the main winding 2 with current. On a partial circle around the pivot point 1 are the two main contacts 3 and 4, the two damping contacts 5 and the articulation contact 6 arranged. The two main contacts 3 and 4 are direct and the damping contacts 5 via each a damping resistor 7 is connected to the ends of the fine step winding 8. The articulation contact 6 is live via an ohmic articulation resistor 9 with the center tapping of the fine step winding 8 tied together. When switching the movable contact 10 in the pivot point 1 from the stationary Main contact 3 on a partial circular path to the fixed main contact 4 are successively the damping contacts 5 and the pivot contact 6 switched on and off again.

The F i g. 2 shows the selection, which is structurally is constructed so that the fulcrum 1 is designed in the form of a "fixed Sch'eifringkreissegmentes. On a pitch circle, the two main contacts 3 and 4, the two of them, are on stationary insulating rods 20 Damping contacts 5 and the articulation contact 6 are arranged. Between the slip ring segment and the two main contacts 3 and 4, the damping contacts 5 and the pivot contact 6 is the

«Running contact 10 on a partial circular path, driven by a selector gear, adjustable. For the sake of clarity, the selector gear and the drive of the running contact IO are not shown. Of the Running contact 10 is equipped with several rails 11 arranged in parallel. In the amount of these rails 11 is additionally arranged a Qiierschiene 12, the length of which is dimensioned so that when driving over from the damping contact 5 to the pivot contact 6 no interruption can occur.

As from F i | {. 3 can be seen, the damping resistors 7 are perpendicular to the insulating rod 20 attached one above the other and connected to the damping contacts 5.

1 sheet of drawings

Claims (3)

Patent claims: 1. Selection for step switches of adjustable transformers, in which the fixed contacts are spatially arranged on an arc and each are mounted on an insulating rod and in which the moving contacts of a selector gear are driven, characterized that optionally two or more than two insulating rods (20), each one fixed on the circular arc Contact (3 to 6) wear, can be mounted with a suitable mutual spacing, such that except for two Main contacts (3, 4) optionally also one or two connected to a damping resistor (7) Damping contacts (5) and / or a pivot contact connected to a pivot resistor (9) (6) are switchable. 2. Pre-selector according to claim 1, characterized in that Haß the resistors (7,9) are each attached to the associated insulating rod (20). 3. Pre-selector according to claim 1 or 2, having a plurality of parallel rails (11) Running contact (10), characterized in that at the level of the fixed contacts (3 to 6) an additional the outer rails (11) laterally protruding and connected to the cross rail (12) arranged is that when damping (S) and articulation contacts (6) are used in the intermediate positions of the Running contact (10) bridged adjacent fixed contacts (3 to 6).