TW202004207A - Characteristic test system of protective relay device - Google Patents

Abstract

An object of this invention is to obtain a characteristic test system of protective relay device capable of confirming soundness of a test signal generated by a test waveform generating circuit provided inside of the protective relay device. A characteristic test system of protective relay device of this invention includes a voltage measuring device (15) which measures a test signal from a test waveform generating circuit (7) for generating a test signal to be inputted to a measuring circuit (6) by a processing signal from an arithmetic processing portion (2) of a protective relay device (1).

Description

Characteristic test system for protecting relay device

The invention relates to a characteristic test system for protecting a relay device, which performs a characteristic test of a protection relay device for protecting electrical equipment from being affected by abnormalities of the power system.

A protective relay device is a device that detects an abnormality such as an accident or failure in the power system, and disconnects the electrical equipment connected to the power system from the power system and protects it.

In order to maintain the proper and correct protection function of the protective relay device, the characteristic test of the protective relay device must be carried out regularly.

In this characteristic test of the protective relay device, the input above the prescribed value (also referred to as the set value. The same applies hereinafter) as the reference for operating the protective function of the protective relay device is supplied to the protective relay device In order to detect the abnormality, and confirm that the time when the abnormality is detected continues for the period of the specified value, the protection will operate. This characteristic test is known as: a method of applying test input from a special tester connected to the connection terminal part of an external device protecting a relay device to perform the test. The special tester can generate a tester suitable for the characteristic test Test signal; and a characteristic test system that can be performed using a test signal generated in a test waveform generating circuit provided inside a protective relay device (for example, refer to Patent Document 1).

(Prior technical literature) (Patent Literature)

Patent Document 1: Japanese Patent Laid-Open No. 2010-284057

In the aforementioned characteristic test of the protective relay device, when the characteristic test is performed using a tester, it is necessary to connect a tester prepared separately from the protective relay device to the protective relay device each time the characteristic test is performed. In addition, when the characteristic test is performed using the test waveform generation circuit built in the protective relay device, since it belongs to a system that cannot confirm the soundness of the test signal generated by the test waveform generation circuit, it has been used The input of the test signal from the test waveform generation circuit corresponding to the test signal generated by simulating the test signal output from the above tester makes it impossible to judge the protection action under the prescribed conditions.

The present invention discloses a technique for solving the above-mentioned problems, the purpose of which is to obtain a characteristic test system for protecting a relay device, which does not need to separately prepare a tester outside in advance to protect the relay device When the characteristic test is carried out by protecting the test waveform generating circuit inside the relay device, the soundness of the test signal generated by the test waveform generating circuit can be confirmed.

The characteristic test system of the protective relay device disclosed in this case is equipped with a measuring device for measuring the test signal generated by the test waveform generating circuit, and is provided in the protective relay device. The protective relay device includes: an input circuit, which is input from electric power The analog electrical quantity of the system; the measurement circuit has an A/D converter that converts the analog electrical quantity from the input circuit into a digital signal; the calculation processing part uses the digital signal from the measurement circuit to perform the calculation process; the output circuit, The signal for operating the interrupter is generated according to the judgment result of the calculation processing part; the display part sets the display item by input from the operation switch part, and displays the signal from the calculation processing part according to the set display item The output; and the test waveform generating circuit generate the test signal input to the measuring circuit by the processing signal from the arithmetic processing section.

According to the characteristic test system for protecting the relay device disclosed in the present invention, since the measuring device for measuring the test signal generated by the test waveform generating circuit is provided, the soundness of the test signal generated by the test waveform generating circuit can be confirmed.

1‧‧‧Protection relay

2‧‧‧Calculation Processing Department

3‧‧‧ Non-volatile memory

4‧‧‧Power

5‧‧‧ Input circuit

6‧‧‧Measurement circuit

7‧‧‧Test waveform generating circuit

7a‧‧‧wave adjustment element

7b‧‧‧adjusted value

8‧‧‧Transmission circuit

9‧‧‧ Output circuit

10‧‧‧Operation switch

10A, 10B, 10C, 10D‧‧‧operation switch

11‧‧‧Display

12‧‧‧Controller

13‧‧‧Interrupter

14‧‧‧Signal conversion unit

15‧‧‧Voltage measuring device

16‧‧‧Time measuring device

51‧‧‧Current measurement circuit

52‧‧‧Voltage measuring circuit

53‧‧‧ Zero-phase current measurement circuit

54‧‧‧ Zero-phase voltage measurement circuit

61‧‧‧A/D converter

62a, 62b, 62c, 62d‧‧‧ input switcher

63a, 63b, 63c, 63d

71‧‧‧D/A converter

72‧‧‧Amplifier

140‧‧‧Amplifying circuit

141‧‧‧Variable resistance

142a, 142b‧‧‧Insulated circuit

C1‧‧‧Special cable

N‧‧‧Open network

T1, T3‧‧‧ output terminal

T2, T4‧‧‧ input terminal

T5‧‧‧Power terminal

Fig. 1 is a block diagram showing the structure of a characteristic test system for a protective relay device according to the first embodiment.

Fig. 2 is an external view showing the schematic configuration of the front of the protective relay device of the characteristic test system of the protective relay device of the first embodiment.

Fig. 3 is an external view showing the schematic configuration of the front of the signal conversion unit of the characteristic test system of the protective relay device according to the first embodiment.

FIG. 4 is a diagram showing the connection structure of the signal conversion unit and the measuring device of the characteristic test system of the protective relay device according to the first embodiment.

Fig. 5 is a diagram showing an example of the display state of the display portion of the protective relay device of the characteristic test system of the protective relay device of the first embodiment.

Fig. 6 is a diagram for explaining the connection configuration of the protective relay device and the signal conversion unit of the characteristic test system of the protective relay device according to the first embodiment and an example of its use.

FIG. 7 is a diagram showing an example of an adjustment screen of the display unit of the protective relay device of the characteristic test system of the protective relay device of Embodiment 1. FIG.

Fig. 8 is a diagram showing an operation flowchart of the characteristic test system for the protective relay device according to the first embodiment.

In the following, based on the preferred embodiment of the characteristic test system for protecting the relay device, a description will be given using drawings. In addition, the same or equivalent parts in the drawings are indicated by the same symbols.

Embodiment 1

Fig. 1 is a block diagram showing the structure of a characteristic test system for a protective relay device according to the first embodiment.

The protective relay device 1 is provided with: an input circuit 5 that inputs analog electrical quantities from the power system; a measurement circuit 6 that has an A/D converter (converter) that converts the analog electrical quantities from the input circuit 5 into digital signals 61; arithmetic processing unit (CPU, central processing unit) 2, is to use the digital signal from the measuring circuit 6 to perform predetermined arithmetic processing; output circuit 9, is based on the results of the judgment of the arithmetic processing unit 2 to generate the interrupter 13 The signal of the operation; the display section 11 sets the display items by input from the operation switch section 10 constituting the operation section, and displays the output from the calculation processing section 2 according to the set display items; and the test waveform generation circuit 7. The test signal input to the measurement circuit 6 is generated by the processing signal from the calculation processing section 2. The test waveform generating circuit 7 is configured to include a D/A converter 71 and an amplifier 72 that convert the output (digital signal) from the calculation processing unit 2 into an analog signal.

Furthermore, the protection relay device 1 further includes: a memory 3 that stores information necessary for the calculation processing of the calculation processing unit 2, a power supply 4 required to protect the operation of the relay device 1, and a controller provided outside 12 and the calculation processing unit 2 through the open field network N (open field network) signal and information transmission and reception interface (transmission I/F) transmission circuit 8 of which the controller 12 is a programmable logic controller ( PLC, programmable logic controller).

The input circuit 5 is an element that converts the analog electrical quantity input from the power system into a level suitable for the subsequent circuit, and has: a current measurement circuit 51, which has an auxiliary converter that detects the current of the power system ( Auxiliary CT); voltage measurement circuit 52, which has an auxiliary transformer (auxiliary VT) that detects the voltage of the power system; zero-phase current measurement circuit 53, which has an auxiliary converter (auxiliary CT) that detects the zero-phase current of the power system ); and the zero-phase voltage measurement circuit 54 is an auxiliary transformer (auxiliary VT) that detects the zero-phase voltage of the power system.

The measurement circuit 6 includes input switches 62a, 62b composed of a multiplexer that switches the signal from the input circuit 5 and the signal from the test waveform generation circuit 7 to the A/D converter 61, 62c and 62d are connected to the input circuit 5 when the protective relay device 1 is used in a general manner, and connected to the test waveform generating circuit 7 when the characteristic test of the protective relay device 1 is performed. In addition, the input switches 62a, 62b, 62c, 62d and the A/D converter 61 are connected through amplifiers 63a, 63b, 63c, 63d. In addition, the measurement circuit 6 also has a reference power supply (also referred to as a reference power supply IC) of the A/D converter 61.

The interrupter 13 is installed in the power system to which the protective relay device 1 is connected, and performs an open circuit operation by a signal from the output circuit 9 to release the power system, thereby removing the electrical equipment connected to the power system from the power The system is switched off for protection.

In addition, the protection relay device 1 is connected to the voltage measurement device 15 and the time measurement device 16 through the signal conversion unit 14.

The signal conversion unit 14 is configured to include an amplifier circuit 140, a variable resistor 141, and insulating circuits 142a and 142b using an insulating transformer, and to supply the test waveform generating circuit 7 through the amplifier circuit 140, the variable resistor 141 and the insulating circuit 142a The output is also supplied to the pulse signal corresponding to the time signal for control of the arithmetic processing section 2 through the insulating circuit 142b.

The protective relay device 1 has an input terminal portion on the input side for connecting the power supply 4, current measurement circuit 51, voltage measurement circuit 52, zero-phase current measurement circuit 53, and zero-phase voltage measurement circuit 54 to the power system, and The output side has an output terminal portion for connecting the signal conversion unit 14, the controller 12, and the interrupter 13.

The signal conversion unit 14 has an input terminal portion T2 as an input terminal for inputting test waveforms and pulse signals on the input side, and an output terminal portion T3 as an output terminal for outputting test waveforms and pulse signals on the output side .

Each output terminal portion T1 that outputs the test waveform signal from the test waveform generating circuit 7 and the pulse output signal from the calculation processing portion 2 and the input terminal portion T2 of the signal conversion unit 14 are connected by each dedicated cable C1 .

The voltage measuring device 15 and the time measuring device 16 are respectively connected to the output terminal portion T3 of the signal conversion unit 14, the voltage measuring device 15 measures the signal of the test waveform from the test waveform generating circuit 7, and the time measuring device 16 measures the The signal output from the pulse of the arithmetic processing unit 2.

Fig. 2 is an external view showing the schematic configuration of the front of the protective relay device of the characteristic test system of the protective relay device of the first embodiment.

As shown in FIG. 2, the front part of the protective relay device 1 includes an operation switch unit 10, a display unit 11, and an output terminal unit T1. The operation switch unit 10 includes operation switches 10A and 10B for switching the display mode and operation switches 10C and 10D for switching the display mode.

Fig. 3 is an external view showing the schematic configuration of the front of the signal conversion unit of the characteristic test system for protecting the relay device according to the first embodiment.

As shown in FIG. 3, the front part of the signal conversion unit 14 has: an input terminal T2 connected to the protective relay device 1; an output terminal T3 connected to a voltage measuring device 15 and a time measuring device 16 The input terminal portion T4 is connected to a calibration machine used as a reference for correcting the signal conversion unit 14; and the power terminal portion T5 is connected to the power supply of the signal conversion unit 14.

In addition, in the panel mounted on the front portion of the signal conversion unit 14 by screws, the terminals are marked near the terminal portions of the input terminal portion T2, the output terminal portion T3, the input terminal portion T4, and the power supply terminal portion T5. The connection object of the connection.

FIG. 4 is a diagram showing the connection structure of the signal conversion unit and the measuring device of the characteristic test system of the protective relay device according to the first embodiment.

As shown in FIG. 4, a voltage measuring device 15 and a time measuring device 16 are connected to the output terminal T3 of the signal conversion unit 14. Furthermore, as shown in FIG. 1, the input terminal portion T2 of the signal conversion unit 14 is connected to the output terminal portion T1 of the protective relay device 1 through a dedicated cable C1.

In addition, FIG. 4 shows a state in which the voltage measuring device 15 and the time measuring device 16 are connected to the output terminal T3. The voltage measuring device 15 is equivalent to the output from the current measuring circuit 51 of FIG. 1 as a measurement. As for the signal output from the test waveform generating circuit 7, the time measuring device 16 is a signal measuring pulse output from the arithmetic processing unit 2 shown in FIG. A measuring device suitable for the output to be measured is connected to the output terminal T3. For example, in FIG. 4, the following is shown: When the current measuring circuit 51 of FIG. 1 is a voltage output for converting an input current, a signal output from the test waveform generating circuit 7 corresponding thereto is output. The voltage is measured by the voltage measuring device 15. The same is true for the sixth figure described later.

With the voltage measuring device 15 or the time measuring device 16, it can be confirmed whether the output from the test waveform generating circuit 7 or the calculation processing section 2 becomes a predetermined value required for the characteristic test.

In addition, a calibration device such as an AC voltage generator can be connected to the input terminal T4, and the accuracy of the signal conversion unit 14 can be confirmed by the measurement device connected to the output terminal T3.

As a result of confirming the accuracy of the signal conversion unit 14, if the accuracy of the signal conversion unit 14 is outside the specified range, by adjusting the variable resistor 141 shown in FIG. 1 built in the signal conversion unit 14, the The signal conversion unit 14 is set in an appropriate and correct state. In addition, the adjustment operation of the variable resistor 141 can be performed by, for example, removing the panel screwed on the body of the signal conversion unit 14.

Fig. 5 is a diagram showing an example of the display state of the display portion of the protective relay device of the characteristic test system of the protective relay device of the first embodiment. This is an example of selecting the screen displayed on the display unit 11 by operating the operation switches 10A, 10B, 10C, and 10D included in the operation switch unit 10 of the protective relay device 1, and shifting to enable the adjustment of the test signal waveform. 3. The mode of confirmation of the pulse signal measured by the calculation processing unit. The adjustment elements (current, voltage) and time measurement are switched by the operation switch of the operation switch unit 10. The adjustment elements are (a) current waveform adjustment (offset), (b) current waveform adjustment (gain), (c) voltage waveform adjustment (offset), (d) voltage waveform adjustment (gain) , (E) The calculation processing unit measures the time output, and the display unit 11 can selectively display the current waveform adjustment screen (offset), current waveform adjustment screen (gain), and voltage waveform adjustment screen (offset) in the direction of the arrow , Voltage waveform adjustment screen (gain), and time confirmation screen.

Fig. 6 is a diagram for explaining the connection configuration of the protective relay device and the signal conversion unit of the characteristic test system of the protective relay device according to the first embodiment and an example of its use. As shown in FIG. 6, the protective relay device 1 and the signal conversion unit 14 are connected to the output terminal portion T1 of the protective relay device 1 and the input terminal portion T2 of the signal conversion unit 14 through a dedicated cable C1. In addition, a voltage measuring device 15 and a time measuring device 16 are connected to the output terminal T3 of the signal conversion unit 14. In addition, in FIG. 6, the display state of the signal flowing through the dedicated cable C1 connecting the output terminal portion T1 of the protective relay device 1 and the input terminal portion T2 of the signal conversion unit 14 is illustrated, and the offset (output Examples of adjustment (A) of the center voltage of the waveform, adjustment (B) of the gain (amplitude of the output waveform), and confirmation (C) of the measurement time (pulse output) of the calculation processing unit. These signals can be confirmed by, for example, displaying on an oscilloscope connected to the output terminal T3.

After determining the adjustment elements (a) to (e) described in Fig. 5, move to the adjustment screen of the test waveform. In the adjustment screen, the adjustment value is increased or decreased by operating the switch, which is reflected in the offset of the output waveform and the amplitude of the waveform. Although there is no adjustment screen for the measurement time confirmation of the calculation processing part, pulse output is still performed by the operation switch operation on the time confirmation screen in Fig. 5.

Fig. 7 is a diagram showing an example of an adjustment screen example (current) of the display unit of the protective relay device of the characteristic test system of the protective relay device of the first embodiment. The display unit 11 displays the waveform adjustment element 7a and the adjustment value 7b. In the adjustment element selection screen of Fig. 5, select the adjustment element of the test waveform, and after selection, move to the adjustment screen of Fig. 7. The adjustment value is increased or decreased by operating the switch. The adjusted value is reflected in the output of the test waveform as shown in Figure 6.

Fig. 8 is a diagram showing an operation flowchart of the characteristic test system for the protective relay device according to the first embodiment.

First, as for preparations before adjustment, the output terminal portion T1 of the protective relay device 1 and the input terminal portion T2 of the signal conversion unit 14 are connected by a dedicated cable C1 to connect the signal conversion unit 14 to the protective relay device 1, and Measuring devices such as the voltage measuring device 15 and the time measuring device 16 are connected to the output terminal portion T3 of the signal conversion unit 14 (step S11). The time measurement device 16 connected to the signal conversion unit 14 performs time confirmation of the pulse output of the calculation processing unit 2 to confirm the measurement time of the calculation processing unit 2 (step S12) (see FIG. 6). If it is within the range of the specified value (Yes in step S13), then proceed to step S14, if it is confirmed that the result is not within the range of the specified value (NO in step S13), then proceed to step S15, and determine to protect the relay 1 End the operation for failure and replacement of the device.

In step S14, select the output element of the test waveform (see Figure 5), output the current test waveform when the output element is the current element (step S16), and output the voltage test waveform when the output element is the voltage element (step S17), When the output element is a zero-phase current element, a zero-phase current test waveform is output (step S18), and when the output element is a zero-phase voltage element, a zero-phase voltage test waveform is output (step S19).

In step S20, if the amplitudes and offset values of the waveforms output in steps S16 to S19 are within the specified value range (Yes), then proceed to step S21, if they are not within the specified value range (No), Then, the process proceeds to step S22, the amplitude of the output waveform is adjusted (refer to FIG. 6), and the process returns to step S20.

In step S21, it is determined whether the adjustment of all the waveforms is completed. If it is completed (Yes), it proceeds to step S23 to start the characteristic test. If it is not completed (No), it returns to step S14.

The basic configuration of the embodiment can be configured by a measuring device that measures the test signal from the test waveform generating circuit 7 provided in the protective relay device 1 without passing through the signal conversion unit 14, and according to this configuration, it can be used as a measurement The voltage measuring device 15 of the device measures the test waveform of the test signal to confirm the soundness of the test signal.

In addition, in the first embodiment, it has the following three functions.

(1) The system can confirm the soundness of the test signal generated by the test waveform generation circuit 7 through the signal conversion unit 14 and can be confirmed to simulate the test signal output from the tester. The signal conversion unit can be calibrated, and the corrected signal conversion unit is used to confirm the test signal.

(2) Equipped with a function to output the time measured by the calculation processing unit 2 as a pulse signal to the outside. The pulse signal is measured using the corrected time measuring device 16. This makes it possible to confirm that the time measured by the calculation processing unit 2 is correct.

(3) Equipped with the function of confirming the generated test signal and assuming that it exceeds the specified value range, the output of the test signal can be adjusted. In the case where the generated test signal exceeds the specified value range due to component degradation, etc., it is equipped with a function that can adjust the offset and amplitude (gain) of the output waveform. Here, the adjustment value related to the waveform adjustment is reflected in the test signal.

According to the above (1)(2), the soundness of the test signal generated by the test waveform generating circuit 7 and the soundness of the time measured by the calculation processing section 2 can be confirmed, so that the characteristic test system can be ensured The reliability of the tests carried out and the traceability of the characteristic test results.

In addition, by carrying out the function of (3) above, a system can be realized in which a sound test signal is constantly input to perform a characteristic test.

The signal conversion unit 14 is composed of an amplifier circuit 140 with input waveforms, insulating circuits 142a, 142b, and a variable resistor 141. The purpose of each is as described in (1)(2) below.

(1) The output waveform is adjusted by arranging the amplifier circuit 140 and the variable resistor 141 in the signal conversion unit. The general amplification factor is a resistance value of ×1, but the amplification factor can be changed by changing the variable resistor 141, and the output waveform can be adjusted. Therefore, when the deviation of the input waveform and the output waveform occurs due to a problem (for example, deterioration) of the insulating transformer constituting the insulating circuits 142a and 142b, the output waveform is adjusted. Since the deviation of the offset of the signal conversion unit 14 cannot be adjusted, the signal conversion unit itself must be replaced.

(2) The internal circuit of the relay device 1 is protected by the insulating transformers of the insulating circuits 142a and 142b. When the internal circuit of the protective relay device 1 is directly connected to the voltage measuring device 15 and the time measuring device 16 as measuring devices without insulation, there may be, for example, electrostatic noise entering due to the touch of a human finger Possibility. The signal conversion unit 14 and the protective relay device 1 are connected by a connector, and the structure is such that a finger of a person does not touch when connected (the connection port is small). After the signal conversion unit 14 is connected and insulated from the protective relay device 1, the voltage measurement device 15 and the time measurement device 16 as measurement devices are connected to confirm the output waveform.

If only the voltage measuring device 15 as the measuring device is used to measure the test waveform, the signal conversion unit 14 is not required.

Whether an insulation transformer is arranged inside the protective relay device 1 or a signal conversion unit with only an insulation transformer, measurement can be performed without problems.

However, when making this structure, the following problems (1) and (2) must be considered.

(1) Insulation transformer is arranged inside the protective relay device 1

In the case of measuring a test waveform with a measuring device, when it exceeds the normal value range, it cannot be determined whether the test signal generated by the protective relay device 1 has a problem that exceeds the normal value or is due to an insulation transformer ( For example, deterioration) and exceed.

(2) Only the signal conversion unit of the insulating transformer

Although the soundness of the signal conversion unit itself can be confirmed by the confirmation of the input and output of the signal conversion unit 14, the output value of the signal conversion unit itself cannot be adjusted, so if there is a problem with the soundness confirmation, the signal conversion must be performed Replacement of the unit.

By providing the signal conversion unit as in the first embodiment, these problems can be solved.

Although the present invention describes exemplary embodiments, the various features, forms, and functions described in the embodiments are not limited to the use of specific embodiments, and may be used individually or in various forms. The combination is used in the embodiment.

Therefore, countless variations that have not been illustrated have been conceived within the technical scope disclosed in the specification of this case. For example, it includes a case where at least one component is deformed, a case where at least one component is added, or a case where at least one component is omitted.

1‧‧‧Protection relay

2‧‧‧Calculation Processing Department

3‧‧‧ Non-volatile memory

4‧‧‧Power

5‧‧‧ Input circuit

6‧‧‧Measurement circuit

7‧‧‧Test waveform generating circuit

8‧‧‧Transmission circuit

9‧‧‧ Output circuit

10‧‧‧Operation switch

11‧‧‧Display

12‧‧‧Controller

13‧‧‧Interrupter

14‧‧‧Signal conversion unit

15‧‧‧Voltage measuring device

16‧‧‧Time measuring device

51‧‧‧Current measurement circuit

52‧‧‧Voltage measuring circuit

53‧‧‧ Zero-phase current measurement circuit

54‧‧‧ Zero-phase voltage measurement circuit

61‧‧‧A/D converter

62a, 62b, 62c, 62d‧‧‧ input switcher

63a, 63b, 63c, 63d

71‧‧‧D/A converter

72‧‧‧Amplifier

140‧‧‧Amplifying circuit

141‧‧‧Variable resistance

142a, 142b‧‧‧Insulated circuit

C1‧‧‧Special cable

T1, T3‧‧‧ output terminal

T2‧‧‧Input terminal

Claims (4)

A characteristic test system for protecting a relay device is provided with a measuring device for measuring a test signal generated by a test waveform generating circuit, and is provided in the protecting relay device. The above-mentioned protecting relay device includes: an input circuit, in which power from The analog electrical quantity of the system; the measuring circuit has an A/D converter that converts the analog electrical quantity from the aforementioned input circuit into a digital signal; the arithmetic processing section uses the digital signal from the aforementioned measuring circuit to perform the arithmetic processing; output The circuit generates a signal to operate the breaker provided in the power system according to the determination result of the calculation processing part; the display part sets the display items by input from the operation switch part and is based on the setting The display items are used to display the output from the arithmetic processing section; and the test waveform generation circuit generates the test signal input to the measurement circuit by the processing signal from the arithmetic processing section. The characteristic test system for protecting a relay device as described in item 1 of the patent application scope, wherein the aforementioned measuring device is a voltage measuring device. The characteristic test system for protecting the relay device as described in item 1 or item 2 of the scope of patent application is provided with: a signal conversion unit, which is provided on the input side of the aforementioned measuring device to perform the test from the aforementioned test waveform generating circuit Signal correction. The characteristic test system for protecting the relay device as described in item 3 of the patent application scope is equipped with a time measuring device that measures the time signal used in the calculation processing section.

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