KR100915243B1 - Test terminal board for watt-hour meter - Google Patents

Abstract

The present invention relates to a power meter test terminal for preventing damage caused by replacement input of a voltage line and a current line between an instrument transformer and an electricity meter, and to measure the power consumption of a multi-phase power consumer. 1. A test terminal block for an electricity meter capable of checking and testing a connection between an output side and an electricity meter, the apparatus comprising: a voltage connection checker for each phase for checking the connection between the instrument transformer and the electricity meter; A current connection checker for each phase for checking the connection of the current transformer and the meter; And an overcurrent breaker for each phase which cuts off the circuit when an overcurrent flows from the meter transformer to the meter. The voltage circuit and the voltage wiring checker of the meter are respectively connected to the output side of the meter transformer through the overcurrent breaker. The current circuit and the current wiring checking unit of the meter are connected to the output side of the current transformer of the meter to prevent an accident due to a miswiring between the meter transformer and the meter.

Description

Test terminal board for watt-hour meter that prevents damage caused by replacement input of voltage line and current line {Test terminal board for watt-hour meter}

The present invention relates to a test terminal block for a wattmeter for checking and testing the connection between the transformer and the meter and installed between the meter transformer and the meter, in particular, generated according to the replacement input of the voltage line and the current line between the meter transformer and the meter. The present invention relates to a test terminal block for wattmeters that prevents damage in advance.

Conventionally, the amount of power used by a consumer is measured as a wattmeter through an instrument transformer (a meter transformer and a current transformer) in a low voltage circuit of a voltage or a high current of high voltage or more.

At this time, in order to check the fault of the instrument transformer, the disconnection of wiring from the instrument transformer, and the reverse phase of voltage and current supplied from the instrument transformer to the electricity meter, the instrument transformer and the electricity meter must be electrically disconnected and inspected. It was very difficult to check.

Therefore, in order to solve this problem, the test terminal block for the meter is installed between the meter transformer and the meter to check whether the voltage and current supplied from the meter transformer to the meter are missing, whether the voltage and current are supplied to the meter in reverse phase, or the meter fails. It is easy to check whether or not.

Hereinafter, a description will be given of a conventional power measurement circuit using such a test terminal block.

5 is a conventional power measurement circuit diagram.

In Fig. 5, reference numeral 10 denotes a power supply, reference numeral 20 denotes a load, reference numeral 30 denotes an instrument transformer PT for stepping down the rated voltage of the power supply 10 having a voltage higher than or equal to 110V, and reference numeral 40 denotes It is an instrument current transformer (CT) for converting and outputting the current flowing to the load 20 in the power supply 10 having a voltage higher than the high voltage or the low voltage power supply 10 for supplying a large current.

Reference numeral 50 is a test terminal block for a wattmeter for receiving the voltage output from the instrument transformer 30 and the current output from the instrument current transformer 40 at the input terminal, and supplying the voltage and current to the wattmeter 60 at the output terminal. . The configuration of the test terminal for power meters is described in detail in Korean Utility Model Publication No. 20-0218273 (2001.03.15.) And 20-0273225 (2002.04.20.).

In FIG. 5, R, S, and T represent each phase of the power supply, and N represents a grounded neutral wire.

1S is a source for converting the current flowing in the R phase to a constant ratio by the current transformer 40 CT1 for instrumentation, and 1L is the current output from the 1S is the first of the test terminal 50 and the wattmeter 60 It is a load returned to the current transformer 40 CT1 for the instrument through the current coil of 1.

P1 is the voltage supplied to the first voltage coil of the watt-hour meter when the voltage of the R phase with respect to the neutral line N is input and is output at 110V when the voltage of the R phase is the rated voltage, and may also refer to the R phase.

2S is a source for converting the current flowing in the S phase to a constant ratio by the current transformer 40 CT2 for instrumentation, and 2L is the current output from the 2S is the first of the test terminal 50 and the wattmeter 60 It is a load returned to the instrument current transformer 40 CT2 via the current coil of 2.

P2 is a voltage supplied to the voltage of the S phase with respect to the neutral line N and output as 110V when the voltage of the S phase is a rated voltage, and is also a voltage supplied to the second voltage coil of the watt-hour meter.

3S is a source for converting the current flowing in the T phase to a constant ratio by the CT current transformer 40 CT3, and 3L is the current output from the 3S is made of the test terminal 50 and the wattmeter 60 It is a load returned to the current transformer 40 CT3 of the instrument via the current coil of 3.

P3 is the voltage supplied to the third voltage coil of the watt-hour meter when the voltage of the T phase with respect to the neutral line N is input and output to 110V when the voltage of the T phase is the rated voltage, and may also refer to the T phase.

P0 is a grounded neutral wire on the secondary side of the instrument transformers 30.

Transformer is generally used to mean the instrument transformer and instrument current transformer, but in the present invention, the transformer means that the instrument transformer 30 and the instrument current transformer 40 is included or means the instrument current transformer 40. .

In constructing such a power measurement circuit, when the output terminals of the test terminal block 50 and the terminals of the electricity meter 60 are connected, the wiring between each terminal must be correctly connected, but the voltage line output from the test terminal block 50 Because of the large number of wires and current lines, even with great care, mistakes can often occur and lead to incorrect wiring.

If any one of the voltage lines P1, P2, and P3 output from the test terminal block 50 is miswired due to a current line, the voltage of 110 V output from the instrument transformer 30 is a power meter 60. There was a problem that the current transformer of the instrument flows to the current coil of () to burn out.

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems described above, and to provide a test terminal block in which an instrument transformer is not burned out even when any one of voltage lines output from the test terminal block is miswired with a current line.

Another object of the present invention is to provide a test terminal block which is easy to check which of the incorrectly wired voltage line and the current line when any one of the voltage lines output from the test terminal block is miswired with the current line.

Still another object of the present invention is to provide a test terminal block which can easily check whether any one of the voltage lines outputted from the test terminal block is incorrectly connected to the current line.

In order to achieve the above object, the test terminal block for an wattmeter to prevent a miswiring between the instrument transformer and the wattmeter according to the present invention is connected to the output side of the meter transformer and the current transformer and the wattmeter to measure the power consumption of the multi-phase power consumer. An instrument test terminal block capable of confirming and testing a connection, comprising: a voltage connection confirming unit for checking a connection between the instrument transformer and a voltage circuit of the electricity meter; A current connection checker for each phase for checking whether the current transformer of the meter and the current circuit of the meter are connected; And an overcurrent breaker for each phase which cuts off the circuit when an overcurrent flows from the meter transformer through the current circuit of the wattmeter, wherein the voltage circuit and the voltage connection checker of the wattmeter are connected to the meter transformer through the overcurrent breaker. Is connected to the output side of the meter, and the current wiring checker is connected to the output side of the current transformer of the meter to prevent damage caused by the replacement input of the voltage line and the current line between the meter transformer and the meter. It features.

In addition, in the test terminal block for the electricity meter according to the present invention, the voltage connection checker of each phase detects the connection between the instrument transformer and the electricity meter by a voltage connection detection unit and outputs a signal for connection. And a voltage connection confirmation display unit for indicating whether or not to be connected by a signal output from the detection unit and the voltage connection detection unit. The current connection confirmation unit of each phase is connected between the current transformer and the power meter by a current connection detection unit. And a current connection detecting unit for detecting whether or not to output a signal for whether or not to connect the signal, and a current connection confirmation display unit displaying whether or not to be connected by the signal output from the current connection detecting unit.

In addition, in the test terminal block for the electricity meter according to the present invention, if any one unconnected signal among the signals output from the respective voltage connection detectors and one of the signals output from the respective current connection detectors are present, The incorrect wiring is detected by a signal output from the incorrect wiring detection unit and the incorrect wiring detection unit which detects that the output circuit of the instrument transformer is incorrectly connected to the current circuit of the electricity meter and outputs a signal for whether or not the wiring is incorrect. The display device may further include a voltage circuit erroneous confirmation display unit for displaying.

In addition, in the test terminal block of the electricity meter according to the present invention, the overcurrent blocking unit is characterized in that the fuse or an electronic circuit for blocking the overcurrent.

Further, in the test terminal block of the wattmeter according to the present invention, the overcurrent blocking unit is 1A

If it exceeds, it is characterized by breaking the circuit.

The test terminal block for a wattmeter according to the present invention as described above has an effect that the instrument transformer is not burned even if any one of the voltage lines output from the test terminal block is miswired with the current terminal of the wattmeter.

In addition, the test terminal block for the watt-hour meter according to the present invention has an effect that can easily find the miswired voltage line and the current line when any one of the voltage lines output from the test terminal block is miswired with the current line.

In addition, the test terminal block for the watt-hour meter according to the present invention has an effect that it is easy to check whether any one of the voltage lines output from the test terminal block is incorrectly connected to the current line.

1 is a circuit diagram in which a test terminal block for a wattmeter according to the present invention is connected between an instrument transformer and an wattmeter

2 is a circuit diagram of a current connection detection unit of the test terminal according to the present invention

3 is a circuit diagram of a voltage connection detecting unit for a test terminal according to the present invention.

4 is a circuit diagram of a misconnection detection unit of a test terminal according to the present invention.

5 is a conventional power measurement circuit diagram

<Description of reference numerals for main parts in the drawings>

10: power supply unit 20: load

30 instrument transformer 40 instrument current transformer

45: over-current blocking unit 50: test terminal block

60: power meter 80: incorrect wiring detection unit

90: incorrect wiring confirmation display unit

The above and other objects and novel features of the present invention will become more apparent from the embodiments of the present invention and the accompanying drawings.

Best Mode for Carrying Out the Invention Embodiments of the present invention will be described below with reference to the drawings.

In addition, in description of this invention, the same code | symbol is attached | subjected to the same code | symbol and the repeated description is abbreviate | omitted.

Example 1

A test terminal block for a wattmeter for preventing damage caused by replacement input of a voltage line and a current line according to the present invention will be described with reference to FIG. 1.

In Fig. 1, reference numeral 45 is connected between the first to third voltage circuits of the wattmeter 60 from the output side of the instrument transformer 30, and if an overcurrent flows from the output of the instrument transformer 30, It is an overcurrent breaker to cut off. The overcurrent blocking unit 45 may use a fuse of about 1A, and may be used by configuring an electronic circuit capable of breaking a circuit at about 1A when the replacement of the fuse is cumbersome.

The 110V voltage output from the meter transformer 30 of each phase is supplied to the voltage circuit terminals P1, P2, and P3 of the electricity meter 60 through the overcurrent cut-off part 45 of each phase, and the test terminal block 50 Supply to the signal voltage source of each of the detection unit (51, 52, 53, 54, 55, 56).

In Fig. 1, reference numerals 51, 53, and 55 denote current connections for detecting whether the current of the current source output from the meter current transformer 40 flows into the electricity meter 60 and outputting a signal for the detection result. Detecting unit 52, 54, 56 is a voltage connection detecting unit for detecting whether the voltage output from the instrument transformer 30 is supplied to the electricity meter 60, and outputs a signal for the detection result.

In Fig. 1, reference numerals 71, 73, and 75 denote current circuits of the electricity meter 60 from the current transformer 40 for the instrument by a signal for the detection result output from the current connection detecting units 51, 53, and 55. The display unit for indicating whether or not the current flows through, and the reference numerals 72, 74, 76 is a power meter (meter) from the transformer transformer 30 by the signal for the detection result output from the voltage connection detection unit (52, 54, 56) 60 is a display unit for displaying whether or not a voltage is supplied to the voltage circuit.

In the electric power measurement circuit connected in this manner, when the output voltage of the instrument transformer 30 and the output current of the instrument current transformer 40 are supplied to the voltage circuit and the current circuit of the electricity meter 60, the display unit 71 ( (72) (73) (74) (75) (76) is not turned on and there is an error in supply of the output voltage of the instrument transformer 30 of each phase and the output current of the instrument current transformer 40 of each phase. The display corresponding to the abnormal phase is turned on.

If the output terminal P1 of the test terminal block 50 is connected to the 1S terminal of the electricity meter 60, the output terminal 1S of the test terminal block 50 is connected to the P1 terminal of the electricity meter 60 and is connected incorrectly. If the output voltage of PT1 of the instrument transformer 30 is supplied to the 1S which is the current terminal of the wattmeter 60 through the overcurrent cut-off unit 45 and the output terminal P1 of the test terminal block 50, the supply voltage The voltage is grounded through 1L, which is a current terminal of the electricity meter 60, and flows to the ground of PT1, so that PT1 of the instrument transformer 30 is short-circuited. In this state, the overcurrent blocking unit 45 cuts off the circuit by sensing the overcurrent, and the voltage connection detecting unit 52 cut off from the instrument transformer 30 by the overcurrent blocking unit 45 is supplied with voltage from PT1. Therefore, the display unit 72 is turned on. On the other hand, the output current of CT1 of the current transformer 40 for the instrument is supplied to the voltage terminal P1 of the wattmeter 60 through the output terminal 1S of the test terminal block 50, so that the first voltage circuit of the wattmeter 60 is closed. Through the P0 terminal of the electricity meter 60, it flows to ground and flows to 1L, which is the ground of CT1. However, since the impedance of the voltage circuit of the electricity meter 60 is very large, the current connection detection unit 51 in the current transformer 40 of the instrument It is judged that the circuit of CT1 is disconnected, and the display part 71 lights.

That is, when the output terminal P1 of the test terminal block 50 is connected to the 1S terminal of the electricity meter 60, and the output terminal 1S of the test terminal block 50 is changed to the P1 terminal of the electricity meter 60 and miswired. The display unit 71 and the display unit 72 turn on, indicating that P1, which is the output of PT1 of the instrument transformer 30, and 1S, which is the output of CT1 of the instrument current transformer 40, are miswired.

Then, at the moment when the output voltage of the instrument transformer 30 is miswired and short-circuited by the current circuit of the electricity meter 60, the overcurrent blocking unit 45 disconnects the circuit between the instrument transformer 30 and the electricity meter 60. Since it cuts off, the instrument transformer 30 is not burned out.

In this way, even when the voltage circuit and the current circuit of the other phases are incorrectly connected, it is possible to confirm which phase the voltage circuit and the current circuit are incorrectly connected by the lighting of each display unit, and the respective overcurrent to the instrument transformer 30 of each phase. Since the blocking unit 45 is connected, when the instrument transformer 30 is connected to the current circuit of the electricity meter 60, each of the over-current blocking units 45 is cut off, and a voltage connection corresponding to a miswired circuit is detected. The unit 52 and the current connection detecting unit 51 detect the incorrectly wired circuit.

In the following, the specific circuit and operation of each current connection detector and voltage connection detector will be described.

2 is a diagram illustrating a circuit of the current connection detecting units 51, 53, and 55.

In FIG. 2, reference numeral 511 denotes a current / voltage converter for converting a current source output from the instrument current transformer 40 into a signal of voltage, and reference numeral 512 denotes a signal output from the current / voltage converter 511. An amplification unit for amplifying, reference numeral 513 is an AC / DC converter for converting and outputting an AC signal from the amplifier 512 into a DC signal, and 514 is an inverting signal of the AC / DC converter 513. NOT gate.

The current / voltage converter 511 of the current connection detectors 51, 53, and 55 converts the current source, which is the output current of the current transformer 40, into a voltage source, and sends it to the amplifier 512, and amplifies it. The unit 512 amplifies the signal in the AC state and sends the signal to the AC / DC converter 513.

The AC / DC converter 513 converts an AC signal into a DC signal, that is, sends an HIGH signal if there is an AC signal, and sends a LOW signal to the NOT gate 514 if there is no AC signal, and the NOT gate 514 is inputted. The signal is inverted and output to the display unit 71.

3 is a diagram illustrating a circuit of the voltage connection detectors 52, 54 and 56.

In FIG. 3, reference numeral 521 denotes a voltage drop which lowers the voltage output from the instrument transformer 30, and reference numeral 523 denotes an AC / AC which converts and outputs an AC signal coming from the voltage drop 521 to a DC signal. A direct current converter, and reference numeral 524 denotes a NOT gate for inverting the signal of the AC / DC converter 513.

The voltage drop unit 521 of the voltage connection detection unit 52, 54, 56 as described above lowers the voltage output from the instrument transformer 30 and sends it to the AC / DC converter 523. Operations of the AC / DC converter 523 and the NOT gate 524 are the same as those of the AC / DC converter 513 and the NOT gate 514 of the current connection detector 51, and thus will be omitted.

Example 2

Hereinafter, in FIG. 1, a detailed circuit and an operation of a miswiring detector and a display unit for detecting and displaying a miswiring will be described.

In FIG. 1, the incorrect wiring detection unit 80 receives respective signals from the current wiring detection units 51, 53, 55 and the voltage connection detection units 52, 54, 56, and the current connection. When any one of the output signals of the detectors 51, 53, and 55 is unwired, and one of the output signal signals of the voltage connection detectors 52, 54 and 56 is unwired, The display unit 90 is turned on.

4 is a diagram illustrating a circuit of the miswiring detector 80.

In FIG. 4, reference numerals 811, 812, and 813 denote diodes connected to the current connection detection units 51, 53, and 55, respectively, and reference numerals 821, 822, and 823 denote voltage connection detection units 52 and 54. 56 is a diode connected to each other, and the reference numeral 83 denotes a signal that the diodes 811, 812, 813 are connected in parallel and the diodes 821, 822, 823 are connected in parallel and output. When the signal of any one of the current connection detection unit 51, 53, 55 is unwired and the signal of the voltage connection detection unit 52, 54, 56 is unwired An AND gate that outputs a HIGH signal when there is a signal.

When there is an output signal from the AND gate in such a miswiring detection unit 80, the display unit 90 turns on so that any one circuit of the instrument transformer 30 and the instrument current transformer 40 is incorrect. It will indicate the connection.

As mentioned above, although the invention made by this inventor was demonstrated concretely according to the said Example, this invention is not limited to the said Example and can be variously changed in the range which does not deviate from the summary.

In the above embodiment, the test terminal block in the case of an electronic wattmeter has been described, but is not limited thereto. In the case of an inductive power meter, P0, 1L, 2L, and 3L may be configured to prevent common grounding in the test terminal block. Of course. In such a case, the overcurrent breaker may be connected to a P0 circuit, which is a ground wire, without connecting to the P1, P2, and P3 circuits of each phase.

Claims (5)

In the test terminal block for the instrument that can check and test the wiring of the meter and the output side of the instrument transformer and current transformer to measure the power consumption of the multi-phase power consumer, A voltage connection checking unit for checking a connection between the instrument transformer and the voltage circuit of the electricity meter; A current connection checker for each phase for checking whether the current transformer of the meter and the current circuit of the meter are connected; And An overcurrent cut-off of each phase to cut off the circuit when the overcurrent flows from the instrument transformer through the current circuit of the wattmeter, The voltage circuit of the watt-hour meter and the voltage connection checking unit are connected to the output side of the instrument transformer through the overcurrent blocking unit, The electric current meter and the current wiring checker of the meter are connected to the output side of the current transformer of the meter to prevent damage caused by the replacement input of the voltage line and the current line between the meter transformer and the meter. Terminal block. The method of claim 1, The voltage connection checking unit of each phase detects the connection between the instrument transformer and the electricity meter by a voltage connection detecting unit and outputs a signal for whether the connection is made to the voltage connection detecting unit and the signal output from the voltage connection detecting unit. Including a voltage wiring confirmation display unit for indicating whether or not to connect, The current connection checker of each phase detects the connection between the current transformer and the wattmeter by a current connection detector, and outputs a signal for whether the current is connected to the current connection detector and the signal output from the current connection detector. The test terminal block for a watt-hour meter, characterized in that it comprises a current connection confirmation display unit for indicating whether or not to connect. The method of claim 2, If there is any unconnected signal among the signals output from each of the voltage connection detectors and one of the signals output from the current connection detectors, the output circuit of the instrument transformer is the current circuit of the electricity meter. A miswiring detection unit for detecting a miswiring and outputting a signal for the miswiring; The power terminal meter test terminal, characterized in that further comprising a voltage circuit incorrect wiring confirmation display unit for displaying whether the wiring is incorrect by the signal output from the incorrect wiring detection unit. The method according to any one of claims 1 to 3, The overcurrent blocking unit is a test terminal block for a wattmeter, characterized in that the electronic circuit for blocking the fuse or the overcurrent. The method of claim 4, wherein The overcurrent cut-off unit is a test terminal block for power meter, characterized in that to cut off the circuit.