CN212301731U - Switch test device - Google Patents

Abstract

The utility model discloses a switch test device, including power end, wiring end, transformer, outdoor test circuit unit and indoor test circuit unit, the power end with the wiring end is connected, and the power end is used for constituting first test circuit with the wiring end, and the transformer is connected with outdoor test circuit unit, and transformer, outdoor test circuit unit and wiring end are used for constituting outdoor test circuit, and indoor test circuit unit is connected with the wiring end, and indoor test circuit unit is used for constituting indoor test circuit with the wiring end. Utilize the utility model provides a test device can detect switching device's outdoor execution part and indoor control part respectively, utilizes test device can be quick effectual the establishment testing environment, when can avoiding adopting traditional detection mode, because the test error that the wiring mistake leads to.

Description

Switch test device

Technical Field

The embodiment of the utility model provides a relate to the railway test technique, especially relate to a switch test device.

Background

With the rapid development of the railway transportation industry, signal equipment is continuously updated, various new construction, reconstruction and overhaul projects are increased day by day, and particularly, the reconstruction of the existing line has great influence on the driving safety. In the line transformation process, switch simulation test is usually carried out after switch equipment is disassembled and replaced so as to verify whether a fault exists in the switch, and the test condition and the simulation test effect of the simulation test directly influence the normal opening and use of the equipment.

The turnout simulation test mode in the prior art can not completely carry out turnout simulation test generally, and the reasons mainly include the following aspects: when the turnout is pulled for testing, only a hand crank and a simple circuit are adopted; when the shaped circuit is combined, heavy safety relays and other equipment are required, which is not beneficial to application; the turnout switch equipment has multiple types, and the test circuit has single function, so that the test equipment has multiple types; the simulation test generally limits that indoor equipment and outdoor equipment need to be tested respectively under the condition that cables are not communicated; the technical levels of testers are different, and technical conditions are easy to omit when a test environment is built, so that a turnout simulation test is not thorough; the test contents are many, and are often ignored due to simple test equipment, so that the difficulty in opening the test is heavy; therefore, a test device which is convenient to carry and simple to operate and can completely complete turnout simulation tests is urgently needed.

SUMMERY OF THE UTILITY MODEL

The utility model provides a switch test device to reach and to detect outdoor execution part and the indoor control part of switching device respectively, and improve the purpose of experimental effect.

The embodiment of the utility model provides a switch test device, which comprises a power end, a wiring end, a transformer, an outdoor test circuit unit and an indoor test circuit unit,

the power supply end is connected with the wiring end, the power supply end and the wiring end are used for forming a first test loop, the transformer is connected with the outdoor test circuit unit, the transformer and the outdoor test circuit unit are used for forming an outdoor test loop,

the indoor test circuit unit is connected with the wiring terminal, and the indoor test circuit unit and the wiring terminal are used for forming an indoor test loop.

Compared with the prior art, the beneficial effects of the utility model reside in that: the utility model provides a test device includes outdoor test circuit unit and indoor test circuit unit for when testing newly-built, all kinds of switch switching devices in the transformation construction, can detect switching device's outdoor execution part and indoor control part respectively through test device, utilize test device can be quick effectual to establish test environment, when can avoiding adopting traditional detection mode, because the test error that the wiring mistake leads to.

Drawings

FIG. 1 is a block diagram of a turnout test device in an embodiment;

FIG. 2 is a block diagram of an outdoor test circuit unit in the embodiment;

FIG. 3 is a schematic diagram of an outdoor test circuit unit in an embodiment;

fig. 4A is a schematic diagram showing a part of the electric circuit in a switch machine of ZD6 type;

fig. 4B is a schematic diagram of a part of the electric circuit of the electric motor in the switch machine of ZD6 model;

fig. 5A is a schematic diagram showing a part of the electric circuit in a switch machine of ZD6EJ type;

fig. 5B is a schematic diagram of a part of the electric circuit of the electric motor in the switch machine of ZD6EJ model;

FIG. 6 is a schematic diagram of another outdoor test circuit unit in an embodiment;

fig. 7 is a schematic representation of a part of the electric circuit in a switch machine of the type ZYJ 7;

fig. 8 is a schematic diagram of a part of the electric circuit of the motor in the type ZYJ7 switch machine;

FIG. 9 is a block diagram of an indoor test circuit unit in the embodiment;

FIG. 10 is a block diagram of another circuit unit for laboratory test in the examples;

FIG. 11 is a schematic diagram of an indoor test circuit unit in an embodiment;

FIG. 12 is a schematic circuit diagram of a switch test apparatus in an embodiment;

FIG. 13 is an external structural view of a switch test apparatus in the example;

fig. 14 is a block diagram of a switch test apparatus in the example.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

Example one

Fig. 1 is a block diagram showing the construction of a switch test apparatus in the embodiment, and referring to fig. 1, the switch test apparatus includes a power source terminal 100, a terminal 200, a transformer 300, an outdoor test circuit unit 400, and an indoor test circuit unit 500.

The power source terminal 100 is connected to the terminal 200, and the power source terminal 100 and the terminal 200 are used to form a first test loop. The transformer 300 is connected to the outdoor test circuit unit 400, and the transformer 300, the outdoor test circuit unit 400, and the terminal 200 are used to form an outdoor test circuit.

The indoor test circuit unit 500 is connected to the terminal 200, and the indoor test circuit unit 500 and the terminal 200 are used to constitute an indoor test circuit.

For example, the switch test device proposed in this embodiment may be used for a detection test of an indoor or outdoor portion of a direct current 220V switch machine (e.g., ZD6, ZY4, ZD6EJ, etc.), and may also be used for a detection test of an indoor or outdoor portion of a three-phase 380V switch machine (e.g., ZYJ7, ZDJ9, S700K, etc.). Accordingly, the power supply end can be connected with 220V alternating current or three-phase 380V alternating current. The terminals can be used for connecting with four-wire, five-wire or six-wire switches, and correspondingly, the terminals comprise an X1 end, an X2 end, an X3 end, an X4 end, an X5 end and an X6 end, wherein the definitions of X1-X6 are the same as the wiring definitions of the switches in the prior art.

By way of example, the transformer preferably represents a transformer.

For example, when the testing device is used for the detection test of the outdoor part of the switch machine, the testing device is connected with the switch machine through the terminal, and the testing device and the motor in the switch machine can form a first testing loop through the power supply end and the terminal, wherein the first testing loop is used as a control loop of the motor. By controlling the action of the positioning operation relay or the reverse position operation relay in the first test loop, the test device can close or open the corresponding relay contact in the control loop, so as to change the flow direction or phase sequence of the current passing through the motor, and further achieve the purpose of controlling the motor to rotate forwards or reversely.

In the case of performing a test of the outdoor part of the switch machine, the test device is connected to the switch machine via the terminal, and in this case, the test device is also connected to a display device, for example, a display diode, in the switch machine via the terminal, and an outdoor test circuit can be formed via the power supply terminals, the transformer, the outdoor test circuit unit, the terminal and the display device, wherein the outdoor test circuit serves as the display circuit of the switch machine.

For example, the outdoor test circuit unit may include a plurality of branches, and a fixed-reverse relay is further configured in the outdoor test circuit unit, and switching between different branches may be implemented by the fixed-reverse relay, so that the outdoor test circuit may constitute a positioning representation test circuit or a reverse representation test circuit.

The indicating relay can be configured in each branch in the outdoor test circuit unit, the indicating relay is connected in series in the indicating loop, the indicating relay can be closed when the indicating loop is normally conducted, the indicating relay can be opened when the indicating loop is abnormally disconnected, and the test device can judge whether the indicating device or the circuit for connecting the indicating device in the switch machine has faults or not by indicating the state of the relay.

Illustratively, when the testing device is used for the detection test of the indoor part of the switch machine, the testing device is connected with the indoor turnout control device through the connecting terminal, and the testing device and the indoor turnout control device can form an indoor test loop through the connecting terminal and the indoor test circuit unit.

When the detection test of the indoor part of the switch machine is carried out, the indoor test circuit unit is used as the load of the indoor turnout control device so as to verify the functional integrity of the indoor turnout control device. For example, if the indoor turnout control device has a display function, the indoor test circuit unit may include a display device, such as a display diode, and if the indoor turnout control device has a motor starting and controlling function, the indoor test circuit unit may further include a motor or an equivalent motor resistor.

In this embodiment, the test device includes outdoor test circuit unit and indoor test circuit unit for when testing newly-built, all kinds of switch points device in the transformation construction, can detect switch points device's outdoor execution part and indoor control part respectively through the test device, utilize the test device can be quick effectual to establish the testing environment, when can avoiding adopting traditional detection mode, because the test error that the wiring error leads to.

Fig. 2 is a block diagram of an outdoor test circuit unit in an embodiment, and referring to fig. 2, in this embodiment, the outdoor test circuit unit includes two branches, one branch includes a first circuit unit 402, the other branch includes a second circuit unit 403, the transformer 300 is connected to the first circuit unit 402 and the second circuit unit 403 through a first relay contact 401, and the first relay contact 401 is used for switching between the first circuit unit 402 and the second circuit unit 403. The transformer 300, the first relay contact 401, the first circuit unit 402, and the terminal 200 are used to constitute a first outdoor test loop. The transformer 300, the first relay contact 401, the second circuit unit 403, and the terminal 200 are used to constitute a second outdoor test circuit.

For example, if the switch machine to be tested is of the ZD6 type, the first outdoor test loop is a positioning indicating test loop and the second outdoor test loop is a reverse indicating test loop. If the point switch to be tested belongs to the ZYJ7 type, the first outdoor test loop is a reverse position indicating test loop, and the second outdoor test loop is a positioning indicating test loop.

Preferably, a display relay is disposed in the outdoor test circuit unit, and whether or not the display circuit is faulty is determined by the state of the display relay during the test. Fig. 3 is a schematic diagram of an outdoor test circuit unit in an embodiment, and referring to fig. 3, a fixed-reverse relay DFJ is arranged in the test device, wherein the DFJ comprises a relay contact DFJ 4, and the DFJ 4 is a first relay contact.

Specifically, the first circuit unit in the first outdoor test circuit includes a first relay BJ4, a first capacitor C4, a first diode D6, a second diode D8, a second relay BJ5, a second capacitor C5, a third diode D7, and a fourth diode D9.

The first capacitor C4 is connected in parallel with the first relay BJ4, the second capacitor C5 is connected in parallel with the second relay BJ5, the first relay contact DFJ 4, the first relay BJ4, the first diode D6, the fourth diode D9 and the first terminal ZD6-X1 are connected in series, wherein the cathode of the first diode D6 is connected with the anode of the fourth diode D9. The first connection ZD6-X1 is also connected in series with a third diode D7, a second relay BJ5, a second diode D8, and a first relay junction DFJ 4, wherein the cathode of the third diode D7 is connected to the anode of the second diode D8 through the second relay BJ 5. A first terminal of the transformer is connected to the first relay contact DFJ 4 and a second terminal of the transformer is connected to the second terminal ZD 6-X3.

Preferably, the first circuit unit further includes a resistor R3, the resistor R3 is used for current limiting, and the cathode of the fourth diode D9 is connected to the first terminal ZD6-X1 through a resistor R3.

The second circuit unit in the second outdoor test circuit includes a third relay BJ1, a third capacitor C1, a fifth diode D4, a sixth diode D10, a fourth relay BJ3, a fourth capacitor C3, a seventh diode D5, and an eighth diode D11.

The third capacitor C1 is connected in parallel with the third relay BJ1, the fourth capacitor C3 is connected in parallel with the fourth relay BJ3, the first relay contact DFJ 4, the third relay BJ1, the fifth diode D4, the eighth diode D11, and the third terminals ZD6-X2 are connected in series, wherein the cathode of the fifth diode D4 is connected with the anode of the eighth diode D11. The third connection ZD6-X2 is also connected in series with a seventh diode D5, a fourth relay BJ3, a sixth diode D10, and a first relay junction DFJ 4, wherein the cathode of the seventh diode D5 is connected to the anode of the sixth diode D10 through the fourth relay BJ 3.

Preferably, the second circuit unit further includes a resistor R2, the resistor R2 is used for current limiting, and the cathode of the eighth diode D11 is connected to the third terminal ZD6-X2 through a resistor R2.

Referring to fig. 3, a reverse operation relay FCJ is also provided in the test apparatus, the FCJ including a contact FCJ1, the FCJ1 being connected in series between the first circuit unit and the first terminal. The testing device is also provided with a fixed operation relay DCJ, wherein the DCJ comprises a joint DCJ 2, and the DCJ 2 is connected between the second circuit unit and the third terminal in series. Type relays LXJ1, LXJ1 are also provided in the test apparatus, including contacts LXJ 11, LXJ 12, LXJ 13.

The test device is further provided with a rectifying unit U1, the input end of the rectifying unit U1 is connected with a power supply end A and a power supply end N respectively, the negative output end of the rectifying unit U1 is connected with a sixth terminal ZD6-X4 through LXJ 11, the positive output end of the rectifying unit U1 is connected with a first terminal ZD6-X1 through LXJ 13, and the positive output end of the rectifying unit U1 is also connected with a third terminal ZD6-X2 through LXJ 12.

Fig. 4A is a schematic diagram showing a circuit part in a ZD6 type switch machine, fig. 4B is a schematic diagram showing a motor circuit part in a ZD6 type switch machine, and referring to fig. 4A and 4B, the testing device can be applied to a test of an outdoor part of a ZD6 type switch machine, and in the test, the testing device is connected with the ZD6 type switch machine through ZD6-X2, ZD6-X1, ZD6-X3 and ZD6-X4 ends. Connected to a 220V power supply through power terminal A, N.

Illustratively, the switch machine positioning bit reversal conversion and the positioning representation test circuit and the bit reversal representation test circuit can be formed by controlling the opening or closing of the FCJ1, the DCJ 2 and the DFJ 4. For example, when a switch is in a reverse position and a positioning operation is performed, the FCJ1 is controlled to be closed during the operation, at the moment, the rectifying unit U1 supplies power to the motor through a first wiring end ZD6-X1 and a wiring end ZD6-X4, the rectifying unit U1, a first wiring end ZD6-X1, a wiring end ZD6-X4 and the motor form a starting circuit for driving a switch machine to act, and after the motor acts in place, the FCJ1 is disconnected and the starting circuit of the motor is cut off. The DFJ 4 commutating turns off the second circuit unit. The DFJ 4, the transformer and the first circuit unit form a positioning indication test loop through a first terminal ZD6-X1, a second terminal ZD6-X3 and an indication diode Z in the switch machine.

If the positioning indicates that the test loop is normal, the first capacitor C4 can not be charged and the first relay BJ4 is opened in the positive half cycle of the alternating current. During the negative half cycle of the alternating current, the loop formed by the transformer, the second diode D8, the second capacitor C5, the third diode D7 and the representation diode Z is conducted, and the second capacitor C5 is charged so that the second relay BJ5 is closed.

When the diode direction is opposite to the predetermined direction, the circuit formed by the transformer, the first capacitor C4, the first diode D6, the fourth diode D9 and the diode Z is conducted in the positive half period of the alternating current, the first capacitor C4 is charged to close the first relay BJ4, the second capacitor C5 is not charged in the negative half period of the alternating current, and the second relay BJ5 is opened. If the diode is disconnected, the circuit is not conducted, the first capacitor C4 cannot be charged, the first relay BJ4 is disconnected, the second capacitor C5 cannot be charged, and the second relay BJ5 is disconnected.

If the short circuit is indicated at the diode, in the positive half cycle of the alternating current, a loop formed by the transformer, the first capacitor C4, the first diode D6, the fourth diode D9 and the indicating diode Z is conducted, and the first capacitor C4 is charged so that the first relay BJ4 is closed; during the negative half cycle of the alternating current, the loop formed by the transformer, the second diode D8, the second capacitor C5, the third diode D7 and the representation diode Z is conducted, and the second capacitor C5 is charged so that the second relay BJ5 is closed.

Based on the above, whether or not there is a fault in the circuit at the diode and the nature of the fault can be determined by the closed and open states of the first relay BJ4 and the second relay BJ 5.

When the switch is positioned and operates to the reverse position, the DCJ 2 and the DFJ 4 are mainly operated, the positioning operation and the reverse position operation are similar in process, and the mode of judging whether the circuit at the position of the diode has faults is not described again.

Fig. 5A is a schematic diagram showing a circuit part in a switch machine of ZD6EJ type, fig. 5B is a schematic diagram showing a circuit part of a motor in a switch machine of ZD6EJ type, and referring to fig. 5A and 5B, ZD6EJ is a six-wire switch machine which includes two sets of switch machines which move in the same direction. During testing, the testing device is connected with a ZD6EJ type switch machine through corresponding terminals and is connected with a 220V power supply through a power supply end A, N.

When performing a ZD6EJ switch machine test, the circuit structure of the outdoor test circuit unit is the same as that shown in fig. 3, and its operation mode is similar to that of ZD6, FCJ also includes a junction FCJ 2, DCJ also includes a junction DCJ 1, the positive output end of the rectifying unit U1 is connected with the fifth terminal ZD6-X6 through LXJ 13 and DCJ 1, and the positive output end of the rectifying unit U1 is connected with the fourth terminal ZD6-X5 through LXJ 12 and FCJ 2. When the test is carried out, the control FCJ 2 and the control DCJ 1 are correspondingly added to move with the FCJ1 and the control DCJ 2, the FCJ 2 and the control DCJ 1 are respectively the same as the closed state and the open state of the FCJ1 and the open state of the DCJ 2, and the second group of point switches are positioned and inverted to be converted by controlling the closed state or the open state of the FCJ 2 and the open state of the DCJ 1.

Fig. 6 is a schematic diagram of another outdoor test circuit unit in the embodiment, and referring to fig. 6, the test apparatus is further provided with a mode relay MSJ including a contact MSJ 4. DFJ further includes a junction DFJ2, DFJ2 being a second relay junction.

Alternatively, referring to fig. 6, the outdoor test circuit unit further includes a fifth relay BJ2, a fifth capacitor C2, and a ninth diode D3.

The fifth capacitor C2 is connected in parallel with the fifth relay BJ2, and the first terminal of the transformer is also connected in series with the fifth relay BJ2, the ninth diode D3, and the second relay junction DFJ 2. The negative pole of the ninth diode D3 is connected to the second relay contact DFJ 2. The second relay contact DFJ2 is connected to the fourth terminal X4 and the fifth terminal X5, and the second relay contact DFJ2 is used for switching between the fourth terminal X4 and the fifth terminal X5.

Preferably, the outdoor test circuit unit further includes a resistor R1, the resistor R1 is used for current limiting, and a negative electrode of the ninth diode D3 is connected to the second relay contact DFJ2 through the resistor R1.

Fig. 7 is a schematic diagram showing a circuit part in a switch machine of the ZYJ7 type, fig. 8 is a schematic diagram showing a circuit part of a motor in a switch machine of the ZYJ7 type, and referring to fig. 4 and 5, the test device shown in fig. 6 can be applied to a test for detecting an outdoor part of a switch machine of the ZYJ7 type in addition to a test for detecting an outdoor part of a switch machine of the ZD6 type. When the ZYJ7 test is performed, the test apparatus is connected to a ZYJ7 type switch machine through X1, X2, X3, X4 and X5 ends. Connected to a 380V power supply through power terminal A, B, C, N.

For example, switching between a switch of ZD6 type and a switch of ZYJ7 type can be achieved by control LXJ 1. Control LXJ1 was closed when the ZYJ7 test was run and control LXJ1 was open when the ZD6 test was run.

Illustratively, the switch machine positioning inversion conversion and the forming of the positioning representation test loop and the inversion representation test loop can be realized by controlling the closing or opening of the FCJ1, FCJ 2, DCJ 1, DCJ 2, DFJ2 and DFJ 4.

For example, when a ZYJ7 type switch machine is tested, the positioning indication test circuit comprises a positioning indication diode circuit and a positioning indication relay circuit, and a switch is in a reverse position, for example, the DCJ 1 and the DCJ 2 are controlled to be closed during operation, at the moment, a three-phase power supply supplies power to the motor through a terminal X5, a terminal X2 and a terminal X1, the three-phase power supply, the terminal X5, a terminal X2, a terminal X1 and the motor form a starting circuit for driving the switch machine to operate, after the motor operates in place, the DCJ 1 and the DCJ 2 are disconnected, and the starting circuit of the motor is cut off. DFJ 4 commutating turns off the first circuit unit. The DFJ 4, the transformer and the second circuit unit form a positioning indication diode loop with a motor and an indication diode Z in the switch machine through a terminal X2 and a terminal X1. The transformer, the fifth relay, the terminal X4, the terminal X1 and the motor in the switch machine form a positioning indication relay loop.

For example, if the positioning indicates that the diode loop is normal, the loop formed by the transformer, the third capacitor C1, the fifth diode D4, the eighth diode D11, the motor coil and the indication diode is conducted during the positive half period of the alternating current, the third capacitor C1 is charged to close the third relay BJ1, and the fourth capacitor C3 cannot be charged during the negative half period of the alternating current to open the fourth relay BJ 3.

If the diode is reversely connected, the third capacitor C1 cannot be charged in the positive half period of the alternating current, the third relay BJ1 is disconnected, the transformer, the seventh diode D5, the fourth capacitor C3, the sixth diode D10, the motor coil and the loop formed by the diode are conducted in the negative half period of the alternating current, and the fourth capacitor C3 is charged to close the fourth relay BJ 3.

If the diode circuit is open, the circuit is not conducted, the third capacitor C1 cannot be charged, the third relay BJ1 is open, the fourth capacitor C3 cannot be charged, and the fourth relay BJ3 is open.

If the short circuit of the diode loop is indicated, in the positive half cycle of the alternating current, a loop formed by the transformer, the third capacitor C1, the fifth diode D4, the eighth diode D11, the motor coil and the indicating diode Z is conducted, and the third capacitor C1 is charged to close the third relay BJ 1; in the negative half period of the alternating current, a loop formed by the transformer, the seventh diode D5, the fourth capacitor C3, the sixth diode D10, the motor coil and the indicating diode is conducted, and the fourth capacitor C3 is charged so that the fourth relay BJ3 is closed.

Based on the above, whether or not the diode circuit has a fault and the nature of the fault can be determined and located by the closed and open states of the third relay BJ1 and the fourth relay BJ 3.

If the positioning indicates that the relay loop is normal, the loop between the terminal X1 and the terminal X4 is conducted, at the moment, the fifth capacitor C2 is charged, so that the fifth relay BJ2 is closed, if the positioning indicates that the relay loop has an open-circuit fault, the fifth relay BJ2 is opened, and whether the positioning indicates that the relay loop has the open-circuit fault or not can be judged according to the closed and opened states of the fifth relay BJ 2.

When the switch is positioned and operates towards the reverse position, the FCJ1, the FCJ 2, the DFJ2 and the DFJ 4 are operated, the positioning operation and the reverse position operation are similar, and the mode of judging whether the circuit at the position of the diode has faults is not repeated.

Fig. 9 is a block diagram of an indoor test circuit unit in an embodiment, and referring to fig. 9, the indoor test circuit unit includes a third circuit unit 501. Illustratively, the third circuit unit 501 may constitute a representation loop with the indoor control part of the switch machine of ZD6 model, wherein the third circuit unit 501 is used as a representation device in the representation loop.

Fig. 11 is a schematic diagram of an indoor test circuit unit in an embodiment, and referring to fig. 11, DFJ further includes a contact DFJ 3, and DFJ 3 is a third relay contact. Specifically, the third circuit unit includes a twelfth diode D1 and an eleventh diode D2. The twelfth pole tube D1 is connected to terminal ZD6-X2 and to terminal ZD6-X3 via DFJ 3. The eleventh diode D2 is connected to terminals ZD6-X1 and to terminals ZD6-X3 via DFJ 3.

Illustratively, a ZD6 indoor flip representation test loop, i.e. a first indoor test loop, may be constructed by a tenth diode D1, DFJ 3, a terminal ZD6-X2, a terminal ZD6-X3, and a switch machine indoor control portion. ZD6 indoor location representation test loop, namely a second indoor test loop, can be formed by an eleventh diode D2, DFJ 3, a terminal ZD6-X1, a terminal ZD6-X3 and a switch machine indoor control part. During the test, a positioning indicating circuit and a flip indicating circuit can be formed by controlling the on or off of the DFJ 3. Illustratively, a positioning indicating circuit is formed when the DFJ 3 is closed, and a flip indicating circuit is formed when the DFJ 3 is opened. Fig. 10 is a block diagram of an indoor test circuit unit in an embodiment, and referring to fig. 10, the indoor test circuit unit includes a fourth circuit unit 502. Illustratively, the fourth circuit unit 502 may be used to constitute a start-up circuit with the indoor control part of a switch of the ZD6 type, or with the indoor control part of a switch of the ZD6EJ type, or with the indoor control part of a switch of the ZYJ7 type, or with the indoor control part of a switch of the ZYJ7 type in cooperation with the third circuit unit 501.

Referring to fig. 11, MSJ further includes junctions MSJ1, MSJ4, and DFJ further includes junctions DFJ 1, DFJ 2. The fourth circuit unit includes a first resistor M-R1, a second resistor M-R2, and a third resistor M-R3. The first resistor M-R1, the second resistor M-R2 and the third resistor M-R3 are connected in a star shape to form a star-shaped resistor, and the star-shaped resistor is connected with a terminal wire. The first resistor M-R1 is connected with a terminal X1, the second resistor M-R2 is connected with a terminal X2 and a terminal X3 through MSJ1 and DFJ 1, and the third resistor M-R3 is connected with a terminal X4 and a terminal X5 through MSJ4 and DFJ 2. The MSJ1 and the MSJ4 are used for switching the indoor test circuit unit and the outdoor test circuit unit.

Referring to fig. 11, a relay LXJ is also provided in the fourth circuit unit, and the LXJ includes a contact LXJ 2. The switch between the ZD6 type switch machine and the ZYJ7 type switch machine can be realized by controlling the closing or opening of MSJ1, LXJ 2, and LXJ 2 is closed when ZD6 test is performed. ZD6 starting loop can be formed by the terminals ZD6-X4, LXJ 2, the second resistance M-R2, the terminal ZD6-X1, the terminal ZD6-X2 and the indoor control part of the ZD6 type switch machine, and the switch machine can be positioned and reversed by controlling DFJ 1, DCJ 2 and FCJ 1.

Taking the positioning of the turnout and the operation towards the reversal position as an example, during the test, the DFJ 1 is closed, the indoor control parts of the ZD6 reversal starting loop are formed by the terminals ZD6-X4 and LXJ 2, the second resistor M-R2, the terminals ZD6-X2 and the ZD6 type switch machine, and after the turnout is started, the DFJ 1 is controlled to be opened to cut off the reversal starting loop. The switch is in the reverse position, and the positioning operation is similar to the above operation, and is not described again.

When ZD6EJ test is carried out, LXJ 2 is closed, ZD6EJ starting loop can be formed by the terminals ZD6-X4, LXJ 2, the second resistance M-R2, the second resistance M-R3, the terminal ZD6-X1, the terminal ZD6-X2, the terminal ZD6-X5, the terminal ZD6-X6 and the indoor control part of the ZD6EJ type switch machine, and the switch machine can realize the positioning reversal switching by controlling DFJ 1 and DFJ 2.

Taking the switch positioning and the reversing operation as an example, during the test, the indoor control part of the ZD6EJ type switch machine forms a ZD6E (J) machine reversing starting loop by closing the DFJ 1, and the terminals ZD6-X4, LXJ 2, the second resistor M-R2, the terminals ZD6-X2 and ZD6EJ, the indoor control part of the ZD6E (J) machine reversing starting loop by closing the DFJ2, and the terminals ZD6-X4, LXJ 2, the second resistor M-R3, the terminals ZD6-X6 and ZD6EJ type switch machine forms a ZD6E (J) machine reversing starting loop, and after the switch is started, the DFJ 1 and the DFJ2 are controlled to be disconnected, and the two reversing starting loops are cut off. The switch is in the reverse position, and the positioning operation is similar to the above operation, and is not described again.

When the ZYJ7 test is performed, LXJ 2 is disconnected, and a ZYJ7 starting circuit, namely a third indoor test circuit, can be formed by a terminal X1, a terminal X2, a terminal X3, a terminal X4, a terminal X5, a star resistor and an indoor control part of a ZYJ7 type switch machine. The positioning starting loop or the reverse positioning starting loop can be formed by controlling the closing or opening of the MSJ1, the MSJ4, the DFJ 1 and the DFJ 2.

For example, when the switch is positioned and operated in a reverse position, the MSJ4, the MSJ1, the DFJ2 and the DFJ 1 are disconnected, the terminal X1, the terminal X2, the terminal X5 star resistor and an indoor control part of a ZYJ7 type switch machine form a ZYJ7 reverse position starting loop, and when the switch is started, the DFJ 1 and the DFJ2 are controlled to be closed, so that the reverse position starting loop is disconnected. The switch is similar to the above in the reverse positioning operation, and the description is omitted.

LXJ further includes a junction LXJ1, which may be configured to form a ZYJ7 representation loop via a terminal X1, a terminal X2, a terminal X3, a terminal X4, a terminal X5, a diode D1, an eleventh diode D2, a first resistor M-R1, a second resistor M-R2, a third resistor M-R3, and an indoor control portion of a ZYJ7 type switch machine, and to form an indoor position representation test loop or an indoor flip representation test loop via closing or opening of controls LXJ1, MSJ3, MSJ4, DFJ 1, DFJ2, and DFJ 3. Taking the indoor reversal as an example to represent a test loop, LXJ1 is closed, MSJ3 and DFJ 3 are opened, an indoor control part of a ZYJ7 type switch machine, a terminal X1, a terminal X3, an eleventh diode D2, a second resistor M-R1 and a ZYJ 3538 form a ZYJ7 reversal to represent a diode loop, and an indoor control part of a MSJ4, a DFJ2 opening terminal X1, a terminal X5, a first resistor M-R1, a third resistor M-R3 and a ZYJ7 type switch machine form a ZYJ7 reversal to represent a relay loop.

Fig. 12 is a schematic circuit diagram of a railroad switch test apparatus in an embodiment, and referring to fig. 12, it includes the indoor test circuit unit and the outdoor test circuit unit shown in fig. 3, 6 and 11. Referring to fig. 12, the testing device is further provided with a contactor JCQ, the JCQ includes contacts JCQ 1, JCQ 2 and JCQ 3, and the JCQ is mainly used for controlling the JCQ to bear the large current impact of the motor action when the power is supplied to or cut off from the switch motor, so as to reduce the electric spark interference. When the test is carried out, firstly, the DCJ and the FCJ are controlled to be closed, then, the JCQ is controlled to be closed, or firstly, the JCQ is controlled to be opened, then, the DCJ and the FCJ are controlled to be opened, so that no large-current electric spark exists on the DCJ and FCJ joint when the DCJ and FCJ act.

Referring to fig. 12, as an embodiment, the testing apparatus is further provided with a relay DFCJ including a contact point DFCJ 1, and the DFCJ 1 may be used to connect a line between the power source terminal a and the terminal X1 when performing an outdoor test, or to connect a start circuit or indicate a circuit when performing an indoor test.

Referring to FIG. 12, the test apparatus is further provided with safety resistors RD1-3, RD1-2, RD 1-1.

Example two

Fig. 13 is an external configuration diagram of a switch test apparatus according to an embodiment, and referring to fig. 13, in addition to the first embodiment, a transformer, an outdoor test circuit unit, and an indoor test circuit unit are disposed in a test chamber.

The test chamber is provided with a panel 1000, and a first power interface 1, a second power interface 2, wiring interfaces (3-1, 3-2), a first button 4 and a second button 5 are provided on the panel 100.

The first power supply interface 1 is connected to the supply terminal A, B, C, N and the second power supply interface 2 is connected to the input terminal A, N of the transformer.

For example, the wiring interface 3-1 and the wiring interface 3-2 may be aviation sockets, the wiring interface 3-1 is used to connect with ZD6 switches, specifically, the wiring interface 3-1 is connected with terminals ZD6-X2, ZD6-X1, ZD6-X3, ZD6-X4, ZD6-X5 and ZD6-X6, the wiring interface 3-2 is used to connect with ZYJ7 switches, and the wiring interface 3-2 is connected with terminals X1, X2, X3, X4 and X5.

For example, the first button 4 and the second button 5 may be used as an outdoor mode button and an indoor mode button for controlling the MSJ1, MSJ2, MSJ3 and MSJ4 relays to suck up and drop down, so as to switch between an outdoor test loop and an indoor test loop.

Illustratively, the first button 4 and the second button 5 may be a set of buttons, the first button 4 and the second button 5 are connected to relays in the outdoor test circuit unit and the indoor test circuit unit, and the relay contacts may be manually controlled to be closed or opened by the first button 4 or the second button 5.

The first button 4 and the second button 5 can also be connected with a controller, and the first button 4 and the second button 5 are used for sending out a test starting command, and the relay contact is automatically controlled to be closed or opened through the controller.

Fig. 14 is a block diagram of a switch test apparatus in the example, and referring to fig. 14, as an embodiment, the test apparatus is configured with a leakage protection unit 6, a power supply control unit 7, a controller 9, a functional circuit unit 10, a button unit 11, and a power supply interface 12.

For example, the controller 9 may be a single chip microcomputer, and the button unit 11 may include a mode button, a fixed operation button, a reverse operation button, an emergency stop button, a phase sequence switching button, and the like.

Referring to fig. 14, the power supply terminal A, B, C, N of the power interface 12 is connected to the power control unit 7 through the earth leakage protection unit 6, and the power control unit 7 is configured to convert the input power supply voltage into the operating voltages of the controller 9, the outdoor test circuit unit 400, and the indoor test circuit unit 500. The controller 9 is connected to the outdoor test circuit unit 400, the indoor test circuit unit 500, and the button unit 11 through the function circuit unit 10.

Illustratively, the power interface 12 may be connected to a 220V power source via power terminal A, N and to a 380V power source via power terminal A, B, C, N.

Illustratively, the functional circuit unit comprises a relay driving circuit, and the controller is connected with a relay in the test device through the relay driving circuit.

The functional circuit unit also comprises a button detection circuit, and the controller can acquire the state of each button in the button unit according to the button detection circuit so as to generate a corresponding control instruction.

The functional circuit unit also comprises a switching value acquisition circuit, and correspondingly, a first relay, a second relay, a third relay, a fourth relay and a fifth relay in the test device are respectively provided with switching value contacts. The switching value contact is used for outputting the on-off states of the first relay, the second relay, the third relay, the fourth relay and the fifth relay, and the controller switching value acquisition circuit is connected with the switching value contact, so that the on-off states of the relays are automatically judged.

The functional circuit unit further comprises a current detection circuit, correspondingly, the testing device is provided with a current sensor, and the controller collects currents of corresponding wiring ends in the wiring interfaces (3-1 and 3-2) through the current detection circuit and the current sensor. Specifically, the current detection circuit comprises an alternating current detection circuit and a direct current detection circuit, an alternating current sensor is arranged at a terminal X1, an alternating current sensor is arranged at terminals X2 and X4, wires at the terminals X2 and X4 share the alternating current sensor, wires at the terminals X3 and X5 share the alternating current sensor, wires at the terminals X3 and X5 share the alternating current sensor, and the alternating current sensor is connected with the alternating current detection circuit. And the terminals ZD6-X1, ZD6-X5 and ZD6-X4 are respectively provided with a DC sensor, and the DC sensors are connected with a DC detection circuit.

For example, when performing an outdoor test, in the process of driving the switch machine by the motor, within a preset turnout transition start-stop time, the controller may receive a current value reported by each current sensor in the start loop, determine whether the current value of the motor is normal or not according to the current value, or determine whether the current value is present, and if the current value is abnormal, control the motor to stop rotating; when the current value in the starting loop is increased from zero to a set range during an indoor test, the timing is started, and when the timing time exceeds a specified action time corresponding to the type of the switch machine, the control counter relay DFJ is switched to cut off the starting loop and automatically switches to a new indicating loop.

As a preferable scheme, two phase sequence detection modules may be adopted, wherein a first phase sequence detection module is connected to a three-phase power source end of the power interface, a second phase sequence detection module is connected to a star-shaped resistor formed by a first resistor M-R1, a second resistor M-R2 and a third resistor M-R3, and a phase sequence conversion module is connected to the three-phase power source end. When the three-phase power accessed by the power interface is in reverse order with the specified phase sequence, a phase sequence switching instruction can be generated through the phase sequence switching button, and at the moment, the controller can change the phase sequence of the three-phase power through the phase sequence conversion module. The controller can be configured to detect the phase sequence of the motor action power supply accessed by the terminal by using the second phase sequence detection module, and the phase sequence is used as the basis for consistency of the phase sequence of the indoor output power supply and the phase sequence of the outdoor switch machine input power supply.

Referring to fig. 14, as an implementation scheme, the testing apparatus further includes an industrial personal computer 8, the industrial personal computer 8 is connected to the controller 9, and the industrial personal computer 8 is configured to receive the test configuration parameters, instruct the controller 9 to perform the detection test, display the test result, and generate the test report through the test configuration parameters.

Illustratively, an electric shock protector can be arranged at the power interface, and electric shock can be prevented through the contact protector, and the test device can be prevented from being overloaded or short-circuited.

Exemplarily, the wiring interface can be internally provided with a detection terminal which is connected with the controller, correspondingly, the wiring plug can be internally provided with a short-circuit wire, the position of the short-circuit wire corresponds to that of the detection terminal, after the wiring plug is inserted, the controller can judge whether the selected wiring plug is matched with the wiring interface through the on-off state of the detection terminal, if not, the controller can control the testing device to be in a shutdown state, and only the matching testing device can start to work.

Illustratively, the three-phase power source end of the power interface can be further provided with a high-voltage relay, and the high-voltage relay is provided with a high-voltage suction disconnecting device for supplying power and supplying power when the low voltage falls down, so that the problems that the test device works abnormally and devices are burnt and the like due to unmatched voltages when the 220V power source end is connected to the three-phase power source are solved.

Illustratively, the step of conducting an outdoor test with the test device comprises:

step 1, selecting the type of a power supply according to the type of a switch machine to be tested, selecting a corresponding wiring interface, and connecting a test device to a wiring board of the switch machine.

For example, in this step, if the switch machine to be tested is a switch machine of ZD6 or a related model, a 220V power supply and a ZD6 wiring interface are selected, and if the switch machine to be tested is a switch machine of ZYJ7 or a related model, a 380V power supply and a ZYJ7 wiring interface are selected.

And 2, inputting basic information such as a unit to which the switch machine to be tested belongs, a station name, a turnout number, a switch machine type and the like by using an industrial personal computer, selecting a test mode, and selecting an outdoor test mode when performing an outdoor test.

And 3, carrying out test operation according to the operation specification.

For example, in this embodiment, the first button may be configured as a positioning operation button, and the second button may be configured as a flip operation button.

Use ZD6 type goat experiment as an example, during the experiment, if current switch is in the opposite position, then can throw the switch through first button location, observe whether the switch can throw and target in place, at the in-process of switch motion, the controller can detect the electric current in the starting circuit to record switch movement time.

When the first circuit unit and the switch mechanism are pulled in place, the first circuit unit and the switch mechanism form a positioning indication test loop, and the controller judges whether the positioning indication test loop has faults or not by detecting the passing states of the first relay and the second relay.

The turnout is pulled in a reversed position through the second button, whether the turnout can be pulled in place or not is observed, and whether the test loop breaks down or not is judged in the reversed position through the controller by detecting the passing states of the third relay and the fourth relay.

The testing device can be configured with a light emitting diode, the light emitting diode is connected with the controller, and the controller can be configured to control the light emitting diode to emit light if the loop is normal, and not to emit light if the loop is abnormal. For example, different color LEDs may be configured in the testing device to distinguish between the positioning and the flip testing. For example, a green LED is used in the positioning indicating test loop and a yellow LED is used in the flip indicating test loop.

For example, an industrial personal computer may be further configured with a test rule for indicating on/off of a contact, a switch machine may be divided into 1, 3 closed or 2, 4 closed, and the test rule for indicating on/off of the contact may be formulated according to the above-mentioned closing relationship, for example:

ZD6 class: disconnecting 13 and 14 contacts, disconnecting 31 and 32 contacts, disconnecting 33 and 34 contacts and disconnecting 03 and 04 shifter contacts; contact points 21 and 22, contact points 23 and 24, contact points 43 and 44 and contact points 01 and 02 are disconnected.

Class ZYJ7 denotes a relay circuit: breaking 11 and 12 joints; breaking the 41 and 42 joints;

class ZYJ7 denotes a diode loop: the contact points 15 and 16 are cut off, the contact points 33 and 34 are cut off, and the contact points 35 and 36 are cut off; the contact points 23 and 24 are disconnected, the contact points 25 and 26 are disconnected, and the contact points 45 and 46 are disconnected.

According to the contact closing type, positioning or reverse position of the point switch, the industrial personal computer can automatically prompt which type of contact breaking operation is required to be carried out at present, a tester breaks off relevant representation contacts in the point switch according to the prompt, the controller transmits the on-off state of the relay in the first circuit unit or the second circuit unit to the industrial personal computer, the industrial personal computer gives the representation state of the turnout, and if the representation is lost, the on-off point is correct. If the ZYJ7 switch machine is used, it also indicates that the relay loop is involved in detection and is distinguished from the first and second circuit units, and automatically verifies whether the loss indication is 11, 12 or 41, 42 indicating contact, and gives an indication when the fault occurs.

Exemplarily, a starting contact on-off test rule can be configured in the industrial personal computer, and according to the type of the point switch, the starting contact on-off test rule is as follows:

ZD6 type: breaking 11 and 12 joints and 05 and 06 breaker joints; the contact points 41 and 42 are cut off, and the contact points 05 and 06 of the breaker are cut off.

Model ZYJ7 host: breaking the 11 and 12 joints, breaking the 13 and 14 joints, and breaking the K1 and K2 breaker joints; the contacts 41 and 42, the contacts 43 and 44 and the contacts K1 and K2 of the breaker are disconnected.

The tester automatically prompts to disconnect the current starting contact in the point switch according to the industrial personal computer, operates the first button or the second button, observes whether the point switch can be pulled, and if the point switch cannot be pulled, indicates that the outdoor starting circuit to be tested makes a correct response after the contact is set to be disconnected, and if the point switch can be pulled, indicates that the starting contact is not disconnected.

The testing device can be used for carrying out friction resistance tests of the main machine and the auxiliary machine, the friction resistance test duration is set according to the action time when the turnout is pulled in place normally, the friction resistance test duration is the sum of the action time when the turnout is pulled in place normally and the pre-delay time (for example, 5s), the controller can be configured to control the starting loop to be always conducted within the friction resistance test duration, whether the point switch can be automatically stopped or not is observed, the point switch stops when the point switch is not started, the point switch is not stopped, the automatic stop indicates that the point switch is stopped and the detection of the stop is finished, and the point switch is determined.

And 4, generating a test report by the industrial personal computer.

During the experiment, the controller communicates with the industrial computer, and the information such as the electric current that will detect, button state, relay state sends for the industrial computer in real time, and the industrial computer integrates above-mentioned information and the basic information of input, the experimental report of this experiment of automatic generation: the basic data of the turnout comprises a turnout number, the type of the turnout machine, a left and a right out-rod of the turnout machine, an opening direction, a contact closing, a positioning reverse position, a phase sequence and a tester, wherein the turnout is disconnected to indicate that the test data has an indication state, the on-off time, the turnout is disconnected to start or is blocked, and the test data has an action time, an action duration, an indication state and the like.

Illustratively, when the indoor test is carried out by the test device, the corresponding wiring interface is selected according to the type of the indoor equipment, the test device is connected to the indoor equipment, the indoor equipment is operated, and whether the indoor equipment can complete basic control work or not and basic representation is completed or not is observed. During the test, the relays in the test device, such as DFJ, MSJ, DFCJ and the like, can be controlled to be abnormally opened so as to judge whether the indoor equipment has a correct indication of the fault state.

ZD6 class: controlling the DFJ 3 to switch off the current turnout indication loop, and controlling the MSJ3 to switch off the turnout indication loop; controlling MSJ1 to cut off a current starting loop; ZD6EJ controls MSJ4 to shut off the auxiliary machinery starting circuit.

Class ZYJ 7: controlling the DFJ 3 to switch off the current turnout indication diode loop, and controlling the MSJ4 to switch off the current turnout indication relay loop; DFCJ 1 is controlled to cut off an X1 starting loop, MSJ1 is controlled to cut off an X2 or X3 starting loop, and MSJ4 is controlled to cut off an X4 or X5 starting loop.

It should be noted that the foregoing is only a preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail with reference to the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the scope of the present invention.

Claims (9)

1. A railroad switch test device is characterized by comprising a power supply end, a wiring terminal, a transformer, an outdoor test circuit unit and an indoor test circuit unit,

the power supply end is connected with the wiring end, the power supply end and the wiring end are used for forming a first test loop, the transformer is connected with the outdoor test circuit unit, the transformer, the outdoor test circuit unit and the wiring end are used for forming an outdoor test loop,

the indoor test circuit unit is connected with the wiring terminal, and the indoor test circuit unit and the wiring terminal are used for forming an indoor test loop.

2. The switch test device as claimed in claim 1, further comprising a first relay contact,

the outdoor test circuit unit comprises a first circuit unit and a second circuit unit, the transformer is connected with the first circuit unit and the second circuit unit through the first relay contact, the first relay contact is used for switching between the first circuit unit and the second circuit unit,

the transformer, the first relay contact, the first circuit unit and the wiring terminal are used for forming a first outdoor test loop, and the transformer, the first relay contact, the second circuit unit and the wiring terminal are used for forming a second outdoor test loop.

3. The switch test device as claimed in claim 2, wherein said first circuit unit includes a first relay, a first capacitor, a first diode, a second relay, a second capacitor, a third diode and a fourth diode,

the first capacitor is connected with the first relay in parallel, the second capacitor is connected with the second relay in parallel,

the first relay contact, the first relay, the first diode, the fourth diode and the first terminal are connected in series, wherein the cathode of the first diode is connected with the anode of the fourth diode,

the first terminal is also connected with a third diode, a second relay, a second diode and a first relay contact in series, wherein the cathode of the third diode is connected with the anode of the second diode through the second relay,

the first end of the transformer is connected with the first relay contact, and the second end of the transformer is connected with the second terminal.

4. The switch test device as claimed in claim 2, wherein said second circuit unit includes a third relay, a third capacitor, a fifth diode, a sixth diode, a fourth relay, a fourth capacitor, a seventh diode and an eighth diode,

the third capacitor is connected with the third relay in parallel, the fourth capacitor is connected with the fourth relay in parallel,

the first relay contact, the third relay, the fifth diode, the eighth diode and the third terminal are connected in series, wherein the cathode of the fifth diode is connected with the anode of the eighth diode,

the third terminal is also connected with a seventh diode, a fourth relay, a sixth diode and a first relay contact in series, wherein the cathode of the seventh diode is connected with the anode of the sixth diode through the fourth relay,

the first end of the transformer is connected with the first relay contact, and the second end of the transformer is connected with the second terminal.

5. The switch test device as claimed in claim 3 or 4, further comprising a fifth relay, a fifth capacitor, a ninth diode and a second relay contact,

the fifth capacitor is connected with the fifth relay in parallel,

the first end of the transformer is also connected with a fifth relay, a ninth diode and a second relay contact in series, wherein the negative pole of the ninth diode is connected with the second relay contact,

the second relay contact is connected with the fourth terminal and the fifth terminal, and the second relay contact is used for switching between the fourth terminal and the fifth terminal.

6. The switch test device as claimed in claim 5, wherein the first relay, the second relay, the third relay, the fourth relay and the fifth relay are respectively provided with switching value contacts,

and the switching value contact is used for outputting the on-off states of the first relay, the second relay, the third relay, the fourth relay and the fifth relay.

7. The switch test device as claimed in claim 1, further comprising a rectifying unit, an input terminal of said rectifying unit being connected to said power source terminal,

the positive output end of the rectifying unit is connected with the first terminal and the third terminal, the negative output end of the rectifying unit is connected with the sixth terminal,

the rectifying unit is used for providing direct current for the first test loop.

8. The switch test device as claimed in claim 1, wherein said indoor test circuit unit includes a third circuit unit and a third relay contact,

the third circuit unit comprises a twelfth diode and an eleventh diode, the twelfth diode and the eleventh diode are connected with the terminal through the third relay contact, the third relay contact is used for switching between the twelfth diode and the eleventh diode,

the twelfth diode, the third relay contact and the terminal are used for forming a first indoor test loop, and the eleventh diode, the third relay contact and the terminal are used for forming a second indoor test loop.

9. The switch test device as claimed in claim 1, wherein said indoor test circuit unit includes a fourth circuit unit,

the fourth circuit unit comprises a first resistor, a second resistor and a third resistor, the first resistor, the second resistor and the third resistor are connected in a star shape to form a star-shaped resistor, the star-shaped resistor is connected with the terminal wire,

and the star-shaped resistor and the terminal are used for forming a third indoor test loop.

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