Technical Field

The invention relates to the mechanical measurement mechanism for measuring contact wear tolerance in breakers used to break load current s and short circuit current s in medium and high- voltage networks in air and gas-insulated cells .

State of the Art

Breakers are devices used to cut of f load current s and short- circuit current s in medium and high-voltage networks . These devices enable the switching on and of f of the circuit with the help of automatic control as well as in idle , load, and especially in short circuit s . Thus , it protect s people from danger and prevent s and minimizes the damage that may occur in low and high-voltage devices . The breakers have both arcs extinguishing and very fast-moving properties . When deenergizing, the breaker must first be opened, then the separator must be opened .

The function of a breaker is to provide the power flow from the circuit in the closed state and to prevent the power flow in the open state . The first of these two tasks creates good contact between the contact element s and the second task is performed electrically by separating the contact element s .

The breaker is expected to perform these two tasks exactly when neces sary . Forcing a breaker that has been closed for a long time to suddenly open the circuit means imposing a heavy task on it. This is where the actual tasks of the breakers emerge. Because at high voltage, it is both difficult and dangerous to open or close the circuit when the electricity is passing .

The breakers are used because they have arc-extinguishing devices that occur when the circuit is under load. Among the duties of the breakers is to open the circuit in a defective state. Accordingly, the breakers separate the devices that came before them from the defective place and prevent the force of failure on those devices. Proper selection, operation, and maintenance of a breaker must also be carried out carefully before it can perform its full function.

With muscle power, it is possible to open and close the breaker contacts, but the breakers need to be opened quickly, so a spring is used to increase the arm speed.

Vacuum breakers ensure that arc faults are extinguished by keeping the user's safety at the highest level in the air and gas-insulated cells used in the building. The breaker unit of the vacuum breakers consists of a high vacuum cylindrical ceramic vessel and two contacts, one fixed and the other movable. The current flowing through the arc while the contacts are disconnected flows until the current reaches the zero point. At the zero point of the current, the arc goes out and the mineral vapor condenses on the contacts. This may cause wear on the contacts.

The vacuum breaker consists of a cylinder breaker tube, which is mostly a ceramic body, and two contacts, movable-fixed, placed in it. The fixed contact is mounted inside the breaker tube with a fixed contact arm. The movable ignition lever, on the other hand, holds the other ignition, springs, and moves through a metal bellow.

Regardless of the materials selected for the contacts, they wear out after a certain lifetime due to the above-mentioned effects .

Since the breaker is closed under vacuum, it will not be possible to disassemble and determine the wear conditions of the contacts and contacts positioned in the tube or to observe them from the outside. For this reason, there will be a need for units that can control the wear status and service life of the contacts without opening the cell.

Since breakers are one of the most important parts of the cell in terms of safety, it is important to check that they work properly. If a breaker that has been closed for a long time is suddenly requested to open the circuit, it will be necessary to know whether the breaker is operating correctly.

The wear of the contact surfaces of the breakers is an important critical control point for the breakers, as it will cause the breakers to not work properly. Since the breaker tube cannot be opened, this condition must also be measured externally. The control of the wear of the contacts on the contact surfaces is provided by electronic wear control units within the normal state of the art .

Utility model applications TR 2019/19920 and TR 2019/19925 are seen to refer to a 36 kV 25 kA 1250 A vacuum breaker used in medium voltage switchgear systems.

The contacts of the said breaker can be mechanically controlled. These mechanical control mechanisms can be equipped with electronic wear control units. Depending on the mechanical connection element s , electronic wear control unit s can control the wear on the contact surfaces of the contact s that contact each other and are separated .

An electronic controller must be as sociated with the contact s within this embodiment . In order for the electronic controller to be operated properly, it is neces sary to control it s operation with software and to display the received data through a digital display .

The addition of these structures to the breaker may cause a significant increase in both the production cost and the operating cost of the breaker .

Performing the wear control with electronic wear control unit s also may create important handicaps in terms of obtaining consistent and accurate result s .

Problems to Be Solved by the Invention

The ob j ect of the invention is to create a mechanical measurement mechanism and display unit used to measure the wear on the contact surfaces of the contact s in vacuum breakers used to cut the load current s and short circuit current s in the medium and high voltage networks in air and gas insulated cells .

The embodiment of the invention includes a display unit that mechanically detect s and mechanically works / shows the abrasions that may occur in the contact s .

In this way, the cost of the lower part s to be used for the detection and display of wear is reduced . On the other hand, thanks to the operating consistency of mechanically operated systems, a more consistent wear detection system has been created .

Description of the Figures

Figure 1. Side sectional view of the breaker and functional components of the breaker,

Figure 2. Detailed view of the contact surfaces,

Figure 3. Detailed view of the mechanical display unit,

Description of References in Figures

Description of Invention

The invention relates to the mechanical measuring mechanism and display unit for measuring the wear on the contact surfaces (3) of the contact elements (2) in the breakers used to break the load currents and short circuit currents in the medium and high voltage networks in the air and gas insulated cells, and comprising a breaker pole (1) having contact elements (2) formed therein, a vacuum tube connection arm (4) associated with the breaker pole (1) by means of bellows for moving at least one of the contact elements (2) and a wear control gear shaft (6) associated with said vacuum tube connection arm (4) .

The wear control gear shaft (6) is associated with at least one pointer (8) movable in the direction of wear on the contact surfaces (3) , and the movements of the said pointer (8) are shown by means of a mechanical display unit (7) .

The pointer (8) preferably depends on the angle of movement of the wear control gear shaft (6) .

After a certain working life of the contact elements (2) , the contact surfaces (3) are worn. In Figure 2, the distance between the contact elements (2) is defined by the contact opening (A) . At least one of the contact elements (2) can be moved with the vacuum tube connection arm (4) to contact or separate from each other.

However, the resulting abrasions pose a significant problem as described above. The wear on the system contact surfaces (3) can be tolerated up to a certain contact surface wear tolerance (B) .

When one of the contact elements (2) is moved to contact each other, the vacuum tube connection arm (4) carries the moving contact element (2) higher than the wear on the contact surfaces (3) .

This movement affects the rotation angle of the wear control gear shaft (6) . Since the pointer (8) connected to the wear control gear (6) will also move depending on the rotation angle of the wear control gear shaft (6) , wear can be monitored via the mechanical display unit (7) where the pointer (8) is operated.

The pointer (8) will preferably be operated within a quadrant (9) formed within the mechanical display unit (7) . The relationship between the quadrant (9) and the pointer (8) may also have different mechanical connections. In this way, the display range and the dimensions of quadrant (9) can be changed .

The quadrant (9) may be provided with various unitary notation marks in and around it. With these marks, the wear on the contact surfaces (3) and the tolerance values for this wear can be shown to the user.

These markings and the indications on the quadrant (9) can be arranged by the lengths of the contact element (2) for the distance contact opening (A) - contact surface wear tolerance (B) and the angular/mechanical relationship between the quadrant (9) and the pointer (8) .

In case the distance from the wear control gear shaft (6) and thus from the vacuum tube connection arm (4) for the movement of the pointer (8) is not sufficient for the display on the quadrant (9) , the dimensions of the wear control gear shaft (6) can be changed or the angular/mechanical relationship between the quadrant (9) and the pointer (8) can be adjusted.

By forming the mechanical wear detection mechanism, the display elements showing the wear can be positioned next to the connection body (5) .

Figure 1 shows an embodiment in which the mechanical display unit (7) is positioned next to the connection body (5) .