SU748568A1 - Automatic short-circuiting device - Google Patents

Description

(54) AUTOMATIC SHORT CUTTER

. .I,

FIELD: electrical engineering, a. specifically for short-circuits, i.e., for switching electrical devices designed to create an art short circuit in an electrical circuit, since the creation of an artificial short circuit (r.) is necessary for the test: no electric machines or apparatus, and also widely used to protect various electrical installations npj / i the occurrence of large currents by creating an artificial short circuit on their input terminals.

A short-circuit automatic switch is known, which contains a contact system, a drive for resetting contacts and a magnetic system | 1. The disadvantage of this device is the complexity of the design and low speed.

Closest to the invention is an automatic short circuiter containing current leads, busbar, a contact system with metal-ceramic overlays, the movable contact of which is placed on the current carrying axis connecting the movable contact to the busbar so that the contact forms

with busbar electrodynamic circuit, magnetic system and calibration element 2.

The specified short-circuiter constantly consumes its work electricity, has low speed and is complicated in design, which does not allow to increase the reliability of operation. The purpose of the invention is to increase (the increase in the reliability of operation.

In order to achieve this goal, the short cover has an insulating two-arm lever located on the same current-carrying axis as the moving contact, the magnetic system of the magnetic system is mounted directly on the conductors, the measur is rigidly fixed at one end of the insulation two-arm, and at the other end of the arm rigidly A movable contact is fixed so that the contact pressure of the contact system is created by both electromagnetic and electrodynamic forces. In addition, to increase the electrodynamic effect, the moving contact can be installed so that, in the open position, it is adjacent to the busbar without a gap.

FIG. a short-circuit design is shown with the passage of rated current (Fjjoj), side view; FIG. 2 shows the short circuit design when the rated current (cw) passes from above (section A-A in FIG. Is rotated); .on FIG. 3 - short circuit design with the passage of a short circuit current (IK.J,) - side view; in fig. 4 shows the short circuit design, with the passage of a short circuit current (I.j.), section B & B in FIG. 3

The auto short loop connector contains a movable contact I, which is hingedly connected by means of current-conducting axle 2 with current-carrying bus 3 (strut), as a result of which a loop electrodynamic circuit is formed. In the contact part, the movable contact 1 is reinforced with a contact pad 4 of metal-ceramic, which eliminates the possibility of welding the contactors upon closing. The movable contact 1 is rigidly connected with one end of the insulating two-arm lever 5 and has a common center of rotation with it on the current-carrying axis 2, and at the other end of the lever the measurine 6 of the electromagnetic system 7 is strengthened.

An insulating double-arm lever 5 is installed on the busbar 3 and is balanced against the center of rotation, and with the help of a calibration spring 8 connected on one side to the bark 6, and on the other to the intermediate lever 9, which is fixed by an adjusting screw 10, presses the moving contact I to the busbar 3. As a result, a working air gap b is formed at the other end of the two-arm isolation lever 5 between the bar 6 and the electromagnetic system 7.

The driving bus 3 is rigidly connected mechanically and electrically with each of the fixed through conductors li in the upper part, and the electromagnetic system 7 with the additional coil 12 is installed in the lower part. Between the busbar 3 and the fixed through conductor i 1, an insulating liner 13 is installed.

The middle stationary through gokoprovod 14 mechanically and electrically connected to the stationary contact 15 by means of an intermediate busbar 16 and joint with the stationary through conductors 11 are rigidly fixed between the insulating walls 17 on the insulating panel 18 by means of insulated studs 19 insulated from them.

Between the contact pad 4 of the movable contact ((that 1 and the fixed contact 15 there is a contact gap in, which is always somewhat smaller than the working air gap 6 and is minimal for a given surge;

The entire structure is covered by a protective casing 20, with the exception of protruding pinouts of fixed through conductors 1 and 4, for connection to the generator and the load.

The insulating panel 18 has racks 21 for mounting and fastening the shorting binder in the workplace.

The operation of the short-circuit automatically occurs as follows.

With the passage of the rated current IHOM. through the fixed through conductors 11 and 14 of the short circuit from the generator to the load (Fig. 1), the magnetizing force of the electromagnetic system 7 is insignificant because it is proportional to the magnitude of the nominal current, and the movable measur 6 will be removed by the calibration spring 8 to the extreme fixed position with the formation of a working air gap b, in which the movable contact 1 lies directly on the current carrying rack 3 without a gap.

When a short circuit current occurs. (Fig. 3 and 4) as a result of malfunctioning (due to insulation breakdown, wire breakage, erroneous actions of service personnel, etc.) above the set current, on which the short connector is calibrated using a calibration screw 10, the magnetizing force of the electromagnetic system 7 increases sharply and the movable core b is quickly attracted, overcoming the counter forces of the calibration spring 8.

In this case, the isolation double-arm lever 5 rotates counterclockwise and the moving contacts I close with fixed contact 15, thereby bridging the generator leads and redistributing the current in the current-carrying parts of the short circuit (Fig. 3).

As a result of the contact closure between the pillar 3 and the movable contact 1, a minimum gap of the loop electrodynamic contour is formed and large electrodynamic compensating forces RDD arise, which are proportional to the square of the short circuit current () and which, together with the forces of the electromagnetic system 7 (Fj create contact Iamat 1, providing reliable inclusion.

The shortcut operation in the controlled mode is as follows.

If it is necessary to create an artificial short circuit, for example for testing electrical machines or devices, an additional 12 ah roller is used to the electromagnetic system 7, when the voltage is applied to which the short circuit is turned on.

When the current is switched off, the moving contact 1 of the shortcircuit returns

to the original fixed disconnected position under the influence of the calibration spring 8.

The proposed shorting device can operate both in three-phase alternating current systems and in direct current.

Claims (2)

Invention Formula . Automatic short-circuit breaker containing current-conductors, busbar, contact system with cermets,. a movable contact of which is placed on a current-carrying axis connecting the movable contact with a current-carrying bus so that said contact forms an electrodynamic circuit with a current-carrying busbar, a magnetic system and a calibration element, characterized in that it is equipped with an insulating two-arm lever to increase reliability, placed on the same current carrying axis. one 6 that the movable contact, the magnetic system magnetic system is installed directly on the tokrovrovods, the measles are rigidly fixed on one end of the insulating two-armed lever, and on the other end of the lever the movable contact is rigidly fixed so that that the contact pressure of the contact system is created by both electromagnetic and electrodynamic forces. 2. A shorting device according to claim I, characterized in that, in order to increase the electrodynamic effect, the movable contact is made so that, in the disconnected position, it is adjacent to the busbar without a gap .. Sources of information taken into account in the examination 1. Chunikhin A. A. Electric / esk apparatuses. M., “Energie, 1965, p. 546. 2. High-speed protection devices for power conversion plants. M., "Informstandartlectro, 1967, p. 55- 6 H02 /) (/ 5J / e / g h I ff ZBHtftamopy no. FIG. Ljl about 15 About 15 HI- 3 D x sS gaitMw s j te / / 6. L / Fig.d 3 7 knagru kk i chgene atom y