Star-delta starting circuit detection tester

Abstract

The utility model relates to the technical field of star-delta starting circuits, in particular to a star-delta starting circuit detection tester. The utility model aims to provide an instrument capable of carrying out wiring detection on a star-delta starting circuit in advance, namely a star-delta starting circuit detection tester, which comprises six digital display voltmeters, three intermediate relays and three alarms, whether wiring is correct or not is judged by observing the voltage values displayed on the six digital display voltmeters and the conditions of the three alarms, and the star-delta starting safety and the wiring accuracy are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of star-delta starting circuits, in particular to a star-delta starting circuit detection tester. Background Art

[0002] When the load has no strict requirements on the motor starting torque but needs to limit the motor starting current, the motor meets the 380V / Δ connection conditions, and the stator winding is connected in a triangle when the motor is operating normally, the star-delta starting method can be used, that is, by converting the motor from star connection to triangle connection, it can achieve the goal of reducing the starting current while maintaining a large starting torque, thereby avoiding the impact on the power grid and electrical equipment. The star connection method is to short-circuit U2, V2, and W2, and add power to U1, V1, and W1. The triangle connection method is to short-circuit U1-W2, V1-U2, and W1-V2 respectively, and add power to the formed triangle joint. The working process of star-delta starting is roughly as follows: 1) After the circuit is started, the main contactor KM1 is closed, and the star contactor KM2 is closed at the same time. The motor is started through the star connection. At this time, the voltage borne by each winding is reduced, resulting in a decrease in the starting current. The starting current provided by the star connection is approximately 1 / 3 of the starting current of the direct delta connection, thereby reducing the requirements for the power grid; 2) When the motor reaches a certain speed, the angular contactor KM3 is closed, and the motor is switched to the delta connection, so that the motor can run normally under full voltage. At this time, the motor winding is directly connected to the power supply to provide maximum power output.

[0003] Due to the particularity of the star-delta starting circuit, the star-delta starting circuit is widely used. In the star-delta starting circuit, it is very important whether the wiring of the star-delta starting main circuit and the control circuit is correct. When the connection method is wrong, it will affect the normal operation of the motor, and in serious cases, the motor may be burned. Therefore, after each wiring is completed, the operator is required to check whether the wiring is correct several times. Even so, the wiring error cannot be completely avoided. Therefore, an instrument that can detect the wiring of the star-delta starting circuit in advance is urgently needed. Summary of the invention

[0004] The utility model aims to provide an instrument which can detect the wiring of a star-delta starting circuit in advance, namely a star-delta starting circuit detection tester.

[0005] The utility model is realized by adopting the following technical solutions:

[0006] A star-delta starting circuit detection tester comprises a first digital voltmeter PV1, a second digital voltmeter PV2, a third digital voltmeter PV3, a fourth digital voltmeter PV4, a fifth digital voltmeter PV5, a sixth digital voltmeter PV6, a first intermediate relay KA1, a second intermediate relay KA2 and a third intermediate relay KA3. The first intermediate relay KA1 is connected in parallel with the first digital voltmeter PV1 to form a first detection branch. The coil of the second intermediate relay KA2 is connected in parallel with the second digital voltmeter PV2 to form a second detection branch. The coil of the third intermediate relay KA3 is connected in parallel with the third digital voltmeter PV3 to form a third detection branch. The first normally closed contact of the first intermediate relay KA1 is connected in series with a first alarm HA1 to form a first alarm branch. The first normally closed contact of the second intermediate relay KA2 is connected in series with a second alarm HA2 to form a second alarm branch. The first normally closed contact of the third intermediate relay KA3 is connected in parallel with the third digital voltmeter PV3 to form a third detection branch. The contact is connected in series with the third alarm HA3 to form a third alarm branch. One end of the first alarm branch, one end of the second alarm branch, and one end of the third alarm branch are connected to one end of the first detection branch, one end of the second detection branch, and one end of the third detection branch through the test switch S to form a first terminal, a second terminal, and a third terminal. The other end of the first alarm branch, the other end of the second alarm branch, and the other end of the third alarm branch are connected to the other end of the first detection branch, the other end of the second detection branch, and the other end of the third detection branch to form a fourth terminal, a fifth terminal, and a sixth terminal. The fourth digital voltmeter PV4 is connected in series with the fifth digital voltmeter PV5 and then connected in parallel with the sixth digital voltmeter PV6 to form a fourth detection branch. The two ends of the fourth detection branch are connected to the first terminal and the third terminal respectively, and the connection node of the fourth digital voltmeter PV4 and the fifth digital voltmeter PV5 is connected at the second terminal.

[0007] When in use, the six terminals U1, U2, V1, V2, W1, and W2 pre-connected with the three-phase winding of the motor in the star-delta starting circuit are not first connected to the motor, but are connected to the first terminal, the second terminal, the third terminal, the fourth terminal, the fifth terminal, and the sixth terminal in the detection tester described in the utility model. The wiring of the star-delta starting circuit is detected by the tester described in the utility model. After ensuring that the wiring is correct, the six terminals in the star-delta starting circuit are respectively connected to the six terminals U1, U2, V1, V2, W1, and W2 of the three-phase winding of the motor.

[0008] The specific methods of the detection test are as follows:

[0009] 1. When the wiring is correct: After the circuit is started, the main contactor KM1 is closed, the fourth digital voltmeter PV4, the fifth digital voltmeter PV5, and the sixth digital voltmeter PV6 all display a voltage of 380V, and the star contactor KM2 is closed at the same time. The first digital voltmeter PV1, the second digital voltmeter PV2, and the third digital voltmeter PV3 show a voltage of 220V, the coil of the first intermediate relay KA1, the coil of the second intermediate relay KA2, and the coil of the third intermediate relay KA3 are energized, and the corresponding first normally closed contacts disconnect the first alarm HA1, the second alarm HA2, and the third alarm HA3 respectively, and the three alarms do not alarm. After the circuit is converted to triangle operation, the angular contactor KM3 is closed, and the motor runs normally at the rated voltage, the six digital voltmeters (PV1, PV2, PV3, PV4, PV5, PV6) all show a voltage of 380V, the coil of the first intermediate relay KA1, the coil of the second intermediate relay KA2, and the coil of the third intermediate relay KA3 are energized, and the corresponding first normally closed contacts disconnect the first alarm HA1, the second alarm HA2, and the third alarm HA3 respectively, and the three alarms do not alarm, indicating that the wiring is correct. (Note: It is well known to those skilled in the art that according to the above description, the three intermediate relays and the three alarms are universal for a wide voltage of 220V-380V).

[0010] 2. When the wiring is wrong:

[0011] (1) The circuit starts the main contactor KM1 and does not close. The six digital voltmeters (PV1, PV2, PV3, PV4, PV5, and PV6) all show no voltage. At the same time, the alarm does not sound or light alarm. This is because the control circuit wiring of the star-delta starting circuit is wrong or the main contactor KM1 is broken or the power supply has no voltage.

[0012] (2) After the circuit is started, the main contactor KM1 is closed, and the three digital voltmeters (PV4, PV5, PV6) all display a voltage of 380V. At the same time, the star contactor KM2 is closed, and the three digital voltmeters (PV1, PV2, PV3) all display a voltage of 220V. When the circuit automatically switches to delta operation, the angle contactor KM3 is not closed, and the three digital voltmeters (PV4, PV5, PV6) all display a voltage of 380V. The three digital voltmeters (PV1, PV2, PV3) all display a voltage of 0V. At the same time, the three alarms sound, which means that the angle contactor KM3 is not closed, the control circuit wiring of the angle contactor KM3 is wrong, or the angle contactor KM3 device is damaged;

[0013] (3) After the circuit is started, the main contactor KM1 is closed, and the three digital voltmeters (PV4, PV5, PV6) all show a voltage of 380V, while the star contactor KM2 is not closed, and the three digital voltmeters (PV1, PV2, PV3) all show a voltage of 0V. At the same time, the alarm sounds. This means that the star contactor KM2 is not closed, the control circuit wiring of the star contactor KM2 is wrong, or the star contactor KM2 device is damaged;

[0014] (4) After the circuit is started, the main contactor KM1 is closed, and the three digital voltmeters (PV4, PV5, PV6) all show a voltage of 380V. At the same time, the star contactor KM2 is closed, and the three digital voltmeters (PV1, PV2, PV3) all show a voltage of 220V. After the circuit automatically switches to delta operation, the angle contactor KM3 is closed, and the three digital voltmeters (PV4, PV5, PV6) all show a voltage of 380V. When only one of the three digital voltmeters (PV1, PV2, PV3) shows 0V, its corresponding intermediate relay is disconnected, the corresponding alarm branch is connected, and the corresponding alarm sounds. This is because the six terminals pre-connected to the three-phase winding of the motor in the star-delta starting circuit are connected incorrectly, that is, the terminals are empty or connected at the same time.

[0015] Furthermore, the tester is also equipped with an anti-static shell and a terminal block. The first intermediate relay KA1, the second intermediate relay KA2, the third intermediate relay KA3, the first alarm HA1, the second alarm HA2 and the third alarm HA3 are all encapsulated in the anti-static shell. The first digital voltmeter PV1, the second digital voltmeter PV2, the third digital voltmeter PV3, the fourth digital voltmeter PV4, the fifth digital voltmeter PV5 and the sixth digital voltmeter PV6, the terminal block, the fuse FU and the test switch S are all located on the outer surface of the anti-static shell. The first terminal, the second terminal, the third terminal, the fourth terminal, the fifth terminal and the sixth terminal are connected to the terminals on one side of the terminal block. When in use, the terminals on the other side of the terminal block are connected to the terminals of the center pre-circuit of the star-delta circuit and the six terminals of the three-phase winding of the motor. The structure is concretized, standardized and integrated, which is convenient to use and can prevent interference from other external signals, thereby improving the detection reliability of the detection tester.

[0016] Furthermore, the anti-static shell is equipped with a handle for easy carrying.

[0017] Furthermore, the first alarm branch also includes a second normally closed contact of the first intermediate relay KA1 connected in series with the first normally closed contact of the first intermediate relay KA1 and the first alarm HA1, so as to further improve the stability of the tester.

[0018] Furthermore, the second alarm branch also includes a second normally closed contact of the second intermediate relay KA2 connected in series with the first normally closed contact of the second intermediate relay KA2 and the second alarm HA2, so as to further improve the stability of the tester.

[0019] Furthermore, the third alarm branch also includes a second normally closed contact of the third intermediate relay KA3 connected in series with the first normally closed contact of the third intermediate relay KA3 and the third alarm HA3, so as to further improve the stability of the tester.

[0020] Furthermore, the alarm is an audible and visual alarm.

[0021] Furthermore, the tester also includes a fuse FU, which plays a role in protecting the safe operation of the tester.

[0022] The beneficial effects produced by the utility model are as follows: the star-delta starting circuit detection tester described in the utility model has a simple structure and is easy to implement, and the detection results are intuitive and clear, and easy to understand. When a wiring error occurs, the operator can find the wiring error location promptly and accurately through the readings of six digital voltmeters and three alarms, thus avoiding accidents; in addition, the detection tester can also be used in training and teaching. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings herein are incorporated into and constitute a part of the specification, show embodiments consistent with the present utility model, and together with the description, are used to explain the principles of the present utility model.

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0025] Figure 1 The utility model is a schematic diagram of the star-delta starting circuit detection tester. DETAILED DESCRIPTION

[0026] In order to more clearly understand the above-mentioned purpose, features and advantages of the utility model, the scheme of the utility model will be further described below. It should be noted that the embodiments of the utility model and the features in the embodiments can be combined with each other without conflict.

[0027] In the description, it should be noted that the terms "first" and "second" are only used for descriptive purposes and should not be understood as indicating or implying relative importance. It should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be internal communication between two elements. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only part of the embodiments of the present invention, rather than all of the embodiments.

[0029] The specific embodiments of the present utility model are described in detail below with reference to the accompanying drawings.

[0030] like Figure 1As shown, a star-delta starting circuit detection tester includes a first digital display voltmeter PV1, a second digital display voltmeter PV2, a third digital display voltmeter PV3, a fourth digital display voltmeter PV4, a fifth digital display voltmeter PV5, a sixth digital display voltmeter PV6, a first intermediate relay KA1, a second intermediate relay KA2, and a third intermediate relay KA3. The first intermediate relay KA1 is connected in parallel with the first digital display voltmeter PV1 to form a first detection branch, the coil of the second intermediate relay KA2 is connected in parallel with the second digital display voltmeter PV2 to form a second detection branch, the coil of the third intermediate relay KA3 is connected in parallel with the third digital display voltmeter PV3 to form a third detection branch, the first normally closed contact of the first intermediate relay KA1 is connected in series with the first alarm HA1 to form a first alarm branch, the first normally closed contact of the second intermediate relay KA2 is connected in series with the second alarm HA2 to form a second alarm branch, and the first normally closed contact of the third intermediate relay KA3 is connected in parallel with the second alarm HA3 to form a second alarm branch. The normally closed contact is connected in series with the third alarm HA3 to form a third alarm branch. One end of the first alarm branch, one end of the second alarm branch, and one end of the third alarm branch are connected to one end of the first detection branch, one end of the second detection branch, and one end of the third detection branch through the test switch S to form a first terminal, a second terminal, and a third terminal. The other end of the first alarm branch, the other end of the second alarm branch, and the other end of the third alarm branch are connected to the other end of the first detection branch, the other end of the second detection branch, and the other end of the third detection branch to form a fourth terminal, a fifth terminal, and a sixth terminal. The fourth digital voltmeter PV4 is connected in series with the fifth digital voltmeter PV5 and then connected in parallel with the sixth digital voltmeter PV6 to form a fourth detection branch. The two ends of the fourth detection branch are connected to the first terminal and the third terminal, respectively, and the connection node of the fourth digital voltmeter PV4 and the fifth digital voltmeter PV5 is connected at the second terminal.

[0031] When in use, the six terminals U1, U2, V1, V2, W1, and W2 pre-connected with the three-phase winding of the motor in the star-delta starting circuit are not first connected to the motor, but are connected to the first terminal, the second terminal, the third terminal, the fourth terminal, the fifth terminal, and the sixth terminal in the detection tester described in the utility model. The wiring of the star-delta starting circuit is detected by the tester described in the utility model. After ensuring that the wiring is correct, the six terminals in the star-delta starting circuit are respectively connected to the six terminals U1, U2, V1, V2, W1, and W2 of the three-phase winding of the motor.

[0032] The specific methods of the detection test are as follows:

[0033] 1. When the wiring is correct: After the circuit is started, the main contactor KM1 is closed, the fourth digital voltmeter PV4, the fifth digital voltmeter PV5, and the sixth digital voltmeter PV6 all display a voltage of 380V, and the star contactor KM2 is closed at the same time. The first digital voltmeter PV1, the second digital voltmeter PV2, and the third digital voltmeter PV3 show a voltage of 220V, the coil of the first intermediate relay KA1, the coil of the second intermediate relay KA2, and the coil of the third intermediate relay KA3 are energized, and the corresponding first normally closed contacts disconnect the first alarm HA1, the second alarm HA2, and the third alarm HA3 respectively, and the three alarms do not alarm. After the circuit is converted to triangle operation, the angular contactor KM3 is closed, and the motor runs normally at the rated voltage, the six digital voltmeters (PV1, PV2, PV3, PV4, PV5, PV6) all show a voltage of 380V, the coil of the first intermediate relay KA1, the coil of the second intermediate relay KA2, and the coil of the third intermediate relay KA3 are energized, and the corresponding first normally closed contacts disconnect the first alarm HA1, the second alarm HA2, and the third alarm HA3 respectively, and the three alarms do not alarm, indicating that the wiring is correct. (Note: It is well known to those skilled in the art that according to the above description, the three intermediate relays and the three alarms are universal for a wide voltage of 220V-380V).

[0034] 2. When the wiring is wrong:

[0035] (1) The circuit starts the main contactor KM1 and does not close. The six digital voltmeters (PV1, PV2, PV3, PV4, PV5, and PV6) all show no voltage. At the same time, the alarm does not sound or light alarm. This is because the control circuit wiring of the star-delta starting circuit is wrong or the main contactor KM1 is broken or the power supply has no voltage.

[0036] (2) After the circuit is started, the main contactor KM1 is closed, and the three digital voltmeters (PV4, PV5, PV6) all display a voltage of 380V. At the same time, the star contactor KM2 is closed, and the three digital voltmeters (PV1, PV2, PV3) all display a voltage of 220V. When the circuit automatically switches to delta operation, the angle contactor KM3 is not closed, and the three digital voltmeters (PV4, PV5, PV6) all display a voltage of 380V. The three digital voltmeters (PV1, PV2, PV3) all display a voltage of 0V. At the same time, the three alarms sound, which means that the angle contactor KM3 is not closed, the control circuit wiring of the angle contactor KM3 is wrong, or the angle contactor KM3 device is damaged;

[0037] (3) After the circuit is started, the main contactor KM1 is closed, and the three digital voltmeters (PV4, PV5, PV6) all show a voltage of 380V, while the star contactor KM2 is not closed, and the three digital voltmeters (PV1, PV2, PV3) all show a voltage of 0V. At the same time, the alarm sounds. This means that the star contactor KM2 is not closed, the control circuit wiring of the star contactor KM2 is wrong, or the star contactor KM2 device is damaged;

[0038] (4) After the circuit is started, the main contactor KM1 is closed, and the three digital voltmeters (PV4, PV5, PV6) all show a voltage of 380V. At the same time, the star contactor KM2 is closed, and the three digital voltmeters (PV1, PV2, PV3) all show a voltage of 220V. After the circuit automatically switches to delta operation, the angle contactor KM3 is closed, and the three digital voltmeters (PV4, PV5, PV6) all show a voltage of 380V. When only one of the three digital voltmeters (PV1, PV2, PV3) shows 0V, its corresponding intermediate relay is disconnected, the corresponding alarm branch is connected, and the corresponding alarm sounds. This is because the six terminals pre-connected to the three-phase winding of the motor in the star-delta starting circuit are connected incorrectly, that is, the terminals are empty or connected at the same time.

[0039] During specific implementation, the tester is also equipped with an anti-static shell and a terminal block. The first intermediate relay KA1, the second intermediate relay KA2, the third intermediate relay KA3, the first alarm HA1, the second alarm HA2 and the third alarm HA3 are all encapsulated in the anti-static shell. The first digital voltmeter PV1, the second digital voltmeter PV2, the third digital voltmeter PV3, the fourth digital voltmeter PV4, the fifth digital voltmeter PV5 and the sixth digital voltmeter PV6, the terminal block, the fuse FU and the test switch S are all located on the outer surface of the anti-static shell. The first terminal, the second terminal, the third terminal, the fourth terminal, the fifth terminal and the sixth terminal are connected to the terminals on one side of the terminal block. When in use, the terminals on the other side of the terminal block are connected to the terminals connected to the center terminal of the star-delta circuit and the six terminals of the three-phase winding of the motor. The structure is concrete, standardized and integrated, easy to use, and can prevent interference from other external signals, thereby improving the detection reliability of the detection tester.

[0040] In specific implementation, the anti-static shell is equipped with a handle for easy carrying.

[0041] In a specific implementation, the first alarm branch further includes a second normally closed contact of the first intermediate relay KA1 connected in series with the first normally closed contact of the first intermediate relay KA1 and the first alarm HA1, so as to further improve the stability of the tester.

[0042] In a specific implementation, the second alarm branch further includes a second normally closed contact of the second intermediate relay KA2 connected in series with a first normally closed contact of the second intermediate relay KA2 and the second alarm HA2, so as to further improve the stability of the tester.

[0043] In a specific implementation, the third alarm branch further includes a second normally closed contact of the third intermediate relay KA3 connected in series with a first normally closed contact of the third intermediate relay KA3 and the third alarm HA3, so as to further improve the stability of the tester.

[0044] In this specific implementation, the alarm is an audible and visual alarm.

[0045] In this specific implementation, the tester also includes a fuse FU, which plays a role in protecting the safe operation of the tester.

[0046] The above is only a specific implementation of the utility model, which enables those skilled in the art to understand or implement the utility model. Although detailed descriptions are given with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments, and they should all be covered by the protection scope of the claims.

Claims

1. A star-delta starting circuit detection tester, characterized in that: The invention comprises a first digital voltmeter PV1, a second digital voltmeter PV2, a third digital voltmeter PV3, a fourth digital voltmeter PV4, a fifth digital voltmeter PV5, a sixth digital voltmeter PV6, a first intermediate relay KA1, a second intermediate relay KA2 and a third intermediate relay KA3. The first intermediate relay KA1 is connected in parallel with the first digital voltmeter PV1 to form a first detection branch. The coil of the second intermediate relay KA2 is connected in parallel with the second digital voltmeter PV2 to form a second detection branch. The coil of the third intermediate relay KA3 is connected in parallel with the third digital voltmeter PV3 to form a third detection branch. The first normally closed contact of the first intermediate relay KA1 is connected in series with the first alarm HA1 to form a first alarm branch. The first normally closed contact of the second intermediate relay KA2 is connected in series with the second alarm HA2 to form a second alarm branch. The first normally closed contact of the third intermediate relay KA3 is connected in parallel with the third alarm The device HA3 is connected in series to form a third alarm branch. One end of the first alarm branch, one end of the second alarm branch, and one end of the third alarm branch are connected to one end of the first detection branch, one end of the second detection branch, and one end of the third detection branch through the test switch S to form a first wiring terminal, a second wiring terminal, and a third wiring terminal. The other end of the first alarm branch, the other end of the second alarm branch, and the other end of the third alarm branch are connected to the other end of the first detection branch, the other end of the second detection branch, and the other end of the third detection branch to form a fourth wiring terminal, a fifth wiring terminal, and a sixth wiring terminal. The fourth digital voltmeter PV4 and the fifth digital voltmeter PV5 are connected in series and then connected in parallel with the sixth digital voltmeter PV6 to form a fourth detection branch. The two ends of the fourth detection branch are respectively connected to the first wiring terminal and the third wiring terminal, and the connecting node of the fourth digital voltmeter PV4 and the fifth digital voltmeter PV5 is connected at the second wiring terminal.

2. A star-delta starting circuit detection tester according to claim 1, characterized in that: The tester is also equipped with an anti-static shell and a terminal block. The first intermediate relay KA1, the second intermediate relay KA2, the third intermediate relay KA3, the first alarm HA1, the second alarm HA2, and the third alarm HA3 are all encapsulated in the anti-static shell. The first digital voltmeter PV1, the second digital voltmeter PV2, the third digital voltmeter PV3, the fourth digital voltmeter PV4, the fifth digital voltmeter PV5, the sixth digital voltmeter PV6, the terminal block, the fuse FU, and the test switch S are all located on the outer surface of the anti-static shell. The first terminal, the second terminal, the third terminal, the fourth terminal, the fifth terminal, and the sixth terminal are connected to one side terminal of the terminal block.

3. A star-delta starting circuit detection tester according to claim 2, characterized in that: The anti-static case is equipped with a carry handle.

4. A star-delta starting circuit detection tester according to claim 3, characterized in that: The first alarm branch further includes a second normally closed contact of the first intermediate relay KA1 connected in series with the first normally closed contact of the first intermediate relay KA1 and the first alarm HA1.

5. A star-delta starting circuit detection tester according to claim 4, characterized in that: The second alarm branch further includes a second normally closed contact of the second intermediate relay KA2 connected in series with the first normally closed contact of the second intermediate relay KA2 and the second alarm HA2.

6. A star-delta starting circuit detection tester according to claim 5, characterized in that: The third alarm branch also includes a second normally closed contact of the third intermediate relay KA3 connected in series with the first normally closed contact of the third intermediate relay KA3 and the third alarm HA3.

7. A star-delta starting circuit detection tester according to claim 6, characterized in that: The alarm is an audible and visual alarm.

8. A star-delta starting circuit detection tester according to any one of claims 1 to 7, characterized in that: The tester also includes a fuse FU.

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