RU219081U1 - Three-phase indicator of visual control of alternating voltage - Google Patents

Abstract

The utility model relates to the electrical industry, and more specifically to electrical indicators, and can be used in electric drives when carrying out repair work on industrial equipment to identify and localize a defect in the output switching circuit of a direct frequency converter. The three-phase indicator of visual control of alternating voltage contains a plastic case, wires for connection in the amount of three pieces in the cable, three current limiters (current-limiting resistors), six LEDs are located on the case, and fasteners. The technical result achieved by the claimed solution is to increase the efficiency of the repair work of industrial equipment due to the localization of the defect in the output switching circuit of the CFC. 3 ill.

Description

The utility model relates to the electrical industry, and more specifically to electrical indicators, and can be used in electric drives when carrying out repair work on industrial equipment to identify and localize a defect in the output switching circuit of a direct frequency converter (hereinafter referred to as CFC).

State of the art

To indicate the presence or absence of electricity in electrical equipment, as well as to indicate the misuse of electrical equipment, it is necessary to have an indicator operating under voltage to provide maintenance personnel with information about the voltage of electrical equipment returned to the network, the presence or absence of faults. In the current state of the art, a large number of solutions are known for measuring and monitoring voltage, for troubleshooting industrial equipment.

For example, a three-level voltage indicator is known from patent document RU 2050551 C1, containing a resistive divider of three resistors, the first output of the first of which is grounded, the first and second generators, the first LED, an inverter, an input terminal for connecting a controlled voltage source, characterized in that that, in order to expand the functionality, a key, a second LED, a limiting resistor, three D-flip-flops, a switch are introduced into it, the first resistor of the resistive divider is made with an average output, the input of the resistive divider is connected through the key to the input terminal of the indicator, the output of the first generator is connected with the control inputs of the key and D-flip-flops, the first and second outputs of the resistive divider are connected respectively to the inputs of the first and second D-flip-flops, the middle output of the first resistor of the resistive divider is connected to the input of the third D-flip-flop, the outputs of the D-flip-flops are connected to the corresponding control inputs of the switch , the output of which is connected to the input of the first LED, the output of which is grounded, the output of the second generator is connected directly to the first input of the switch and to the fourth input through the inverter, the second input of the switch is connected to an additional power source, the third input is grounded, the output of the second LED is connected to indicator input terminal, and the input is grounded. The disadvantage of the presented solution is the impossibility of localizing the defect in the network when it is detected.

A three-phase switch cabinet potential indicator is known from patent document CN 211236005, which contains a mounting frame and a potential indicator, an installation cavity is made in the rear of the mounting frame with a hole on the upper surface, a potential indicator is inserted and mounted in the installation cavity, and the lower end of the potential indicator is welded to mounting plate; according to the utility model, the design is simple, along the periphery of the potential indicator, a mounting frame is additionally arranged; the potential indicator is placed in the mounting cavity with a hole in the upper surface of the mounting frame; the potential indicator plug is inserted into the lower end of the mounting cavity; the arcuate lower end of the insert plate presses on the locking rod of the cylinder; the reflective ring on the surface of the lock rod extrudes the spring in the cylinder; and when the arcuate groove of the insert plate is located on one side of the locking rod, the conical end of the locking rod is inserted into the arcuate groove to fix the potential indicator, so that when the potential indicator is replaced or disassembled, the potential indicator does not need to be fixed with a bolt again, and the convenience of replacing the potential indicator is improved . The disadvantage of this solution is the narrow scope, lack of efficiency for the localization of equipment faults.

As a prototype of the claimed solution, a device for indicating the presence of an alternating voltage can be taken (patent document RU 2034303 C1), containing a three-color indicator, consisting of the first and second LEDs of different colors of luminescence, emitting to a common light guide, the first output of the indicator is connected through the first current limiting element with the first terminal of the device for connecting the first terminals of the voltage source and the switching element, the second terminal through the second current limiting element is connected to the second terminal of the device for connecting the second terminals of the voltage source and the load, and the middle terminal of the indicator is connected to the third terminal of the device for connecting the second output of the switching element and the first output of the load, the first and second diodes, characterized in that, in order to simplify the implementation of the device, the cathodes of the first and second LEDs are connected to the middle output of the three-color indicator, the cathodes of the first and second diodes, respectively, to the first and second outputs of the three-color indicator, and the anodes to its average conclusion. The disadvantages of the solution are the complexity of the design, the lack of efficiency in point detection of faults during the repair of industrial equipment.

The claimed technical solution is designed to eliminate the identified shortcomings. The technical result achieved by the claimed solution is to increase the efficiency of the repair work of industrial equipment due to the localization of the defect in the output switching circuit of the CFC.

Disclosure of the essence of the utility model.

The task is solved, and the technical result is achieved due to the following set of essential features of the utility model: a three-phase indicator for visual control of alternating voltage contains a plastic case, wires for connection in the amount of three pieces in the cable, three current limiters (current-limiting resistors), there are six on the case LEDs to indicate the correct operation of the six keys of the VFC inverter, fasteners.

The claimed technical solution is disclosed with the help of drawings and diagrams. Figure 1 shows a general view of the claimed solution, figure 2 is a photograph of the finished product, figure 3 is an electrical circuit diagram of the indicator, figure 4 is a switching circuit for inverting the LFC, figure 5 is a transistor switching diagram; figure 6 is a diagram explaining the operation of the utility model; figure 7 - diagram of the indicator connection to the output terminals of the NFC - UVW, connected in parallel to the electric motor, with the position of the power switches T1-T6, as shown in figure 6 (a).

The numbers in the figures indicate:

1.LEDs for indication 1;

2. LEDs for indication 2;

3. LEDs for indication 3;

4. LEDs for indication 4;

5. LEDs for indication 5;

6. LEDs for indication 6;

7. Indicator housing;

8. Fixings;

9. Cable with U, V, W wires;

10. Current limiting resistors;

11. Inventory;

12. Motor;

13. Indicator;

14. Object of study;

T1-T6. Power switches of transistors.

The dynamics of the utility model.

When using the utility model, three indicator input wires (U, V, W) are connected to the output terminals of a low-voltage frequency converter (LFC), usually marked - UVW, in parallel with the motor load.

The figure 4 shows the switching circuit for inverting the LFC, where T1-T6 are the power switches of the transistors. Figure 5 shows a transistor switching diagram. It can be seen that three transistors are turned on at any given time.

When operating the LFC with a connected indicator, you can visually observe the presence or absence of voltage, as well as its polarity at the output terminals of the LFC.

Figure 6 is a diagram illustrating the operation of the utility model.

The diagram shows a variant of the correct switching of the power switches of the LF inverter, in which there will be an appropriate indication order on the three-phase indicator for visual control of the alternating voltage.

If the switching inverter is working properly, the LEDs on the indicator will turn on, as shown in the diagram.

If there is a malfunction in the switching circuit of the inverter, due to which the power switches T1-T6 do not work properly, for example, one of the keys does not open completely or does not close completely, in this case, the LED indicator will show which of the LEDs does not work in accordance with as shown in the diagram.

For example, figure 7 shows the connection diagram of the indicator to the output terminals of the NFC - UVW, connected in parallel to the electric motor, with the position of the power switches T1-T6, as shown in the diagram of figure 6 (a).

In the diagram of figure 7, the arrows along the conductors indicate the direction of the current from a higher potential to a lower one with open transistors (power switches) T1, T5, T6, and closed T4, T3, T2.

With a certain direction of current in the UVW circuits, certain LEDs will light up. With the position of the switching transistors of the inverter T1-T6, as shown in this diagram, the indicator will have LEDs 2, 3, 6. With each of the 6 states of the inverter transistors shown in diagram 3, certain LEDs will light up on the indicator.

Consider the presence of a fault in the inverter, for example, the transistor T1 does not work and is always closed, i.e. only two transistors T6 and T5 are open (diagram of figure 7). In this case, LED 2 will not glow, since the cathode-anode potential difference on LED 2 is equal to zero. Similarly, using this indicator, you can determine the idle transistor in the VFC inverter.

The proposed technical solution provides an opportunity to see which of the 6 keys of the CFC inverter is not working correctly, which allows you to speed up the process of localizing the defect in the output switching circuit of the CFC.

The claimed utility model is new, industrially applicable, provides an increase in the efficiency of the repair of industrial equipment.

Claims (1)

Three-phase indicator of visual control of alternating voltage, containing a housing with fasteners, on which LEDs are located, characterized in that the indicator includes six LEDs to indicate the correct operation of six inverter keys of a direct frequency converter, forming three pairs of parallel-back-to-back LEDs, three current-limiting resistor, wires U, V, W, while one of the midpoints of each pair of LEDs are connected to each other, and the other midpoints of each pair of LEDs are connected to the wires U, V, W through the corresponding current-limiting resistors for connection to the output terminals of the direct frequency converter.

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