CN218824498U - Characteristic current increment type low-voltage CT transformation ratio tester - Google Patents

Abstract

The utility model discloses a characteristic current increment type low-voltage CT transformation ratio tester, which comprises a tester suitcase, wherein a control panel is arranged in the tester suitcase, the control panel cuts off one side of the tester suitcase and seals a control cavity, a PCB and a switch are arranged in the control cavity, and the PCB and the switch are connected through a wire; the control panel is provided with a slot hole for inserting the switch, the control panel is also provided with a display screen and three clamp meter current interfaces, and the three clamp meter current interfaces are respectively connected with a voltage wire clamp, a secondary clamp meter and a zero wire clamp. This characteristic current increment formula low pressure CT transformation ratio tester, once wiring through the fastener joint by the survey current transformer go out the exposed live point of line side can, totally not restricted by box space and female interval of arranging, the joint is very convenient, has very big advantage, the measuring method of initiative injection type does not receive load current's influence totally, load underload, heavy load all can obtain accurate result.

Description

Characteristic current increment type low-voltage CT transformation ratio tester

Technical Field

The utility model relates to a CT transformation ratio tester technical field specifically is a characteristic current increment formula low pressure CT transformation ratio tester.

Background

The low-voltage current transformer is used as a current precision measurement induction part, has wide application at each node of a low-voltage distribution network, plays a very important role in current measurement, electric energy measurement and synchronous line loss statistical analysis, has very critical accuracy of current ratio, and is a parameter which is frequently required to be measured in daily routing inspection and line loss investigation work, so that the simple and easy-to-use online CT transformation ratio tester has very large using amount.

The distribution network system of low pressure has numerous cubical switchboard, power equipment such as looped netowrk cabinet, and inside all is equipped with the current transformer of measurement usefulness, because cabinet body inner space is narrow and small, the wiring is intensive, the transformer mounting means is mostly the form of wearing to the heart, ordinary online low pressure CT transformation ratio tester need encircle the cable completely or female the arranging test primary current with the great open type current calliper of volume or flexible current coil, but the condition joint degree of difficulty that is the copper bar when the primary current carrier is very big, especially it is bigger at female narrow local operation degree of difficulty of arranging the interval, can not realize the transformation ratio even and measure.

In addition, the traditional transformation ratio tester mainly measures according to the field load current, and when the field load current is small, the measurement precision is extremely low, and even an error result appears.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a characteristic current increment formula low pressure CT transformation ratio tester has and does not receive box space and female spacing restriction of arranging completely, and the joint is very convenient, has very big advantage, and the measuring method of initiative injection type does not receive load current's influence completely, and load underloading, heavy load all can draw the advantage of accurate result, have solved the problem among the prior art.

In order to achieve the above object, the utility model provides a following technical scheme: a characteristic current increment type low-voltage CT transformation ratio tester comprises a tester suitcase, wherein a control panel is arranged in the tester suitcase, the control panel cuts off one side of the tester suitcase and closes a control cavity, a PCB and a switch are arranged in the control cavity, and the PCB and the switch are connected through a lead;

the control panel is provided with a slot hole for inserting the switch, the control panel is also provided with a display screen and three clamp meter current interfaces, and the three clamp meter current interfaces are respectively connected with a voltage wire clamp, a secondary clamp meter and a zero wire clamp;

the voltage wire is clamped at an exposed conducting point on the side of the outgoing wire P of the tested current transformer;

the secondary split-core type ammeter is connected to a secondary outgoing line of the measured current transformer;

the zero line wire is clamped at the zero line or the exposed conducting points of the zero row.

Preferably, the display screen and the three clamp meter current interfaces are respectively connected to the PCB board through wires.

Preferably, the four end corners of the control panel are provided with screw holes, the four ends of the tester suitcase are provided with studs, and bolts penetrating through the screw holes of the control panel are meshed with the studs.

Preferably, the portable tester case comprises a case body and a cover plate, the case body and the cover plate are connected through a hinge, and the control panel is flush with the opening of the case body.

Preferably, the secondary outgoing line of the tested current transformer is used for connecting a three-phase line and a single-line or three-phase load.

Compared with the prior art, the beneficial effects of the utility model are as follows:

this characteristic current increment formula low pressure CT transformation ratio tester, once wiring through the fastener joint by the survey current transformer go out the exposed live point of line side can, totally not restricted by box space and female interval of arranging, the joint is very convenient, has very big advantage, the measuring method of initiative injection type does not receive load current's influence totally, load underload, heavy load all can obtain accurate result.

Drawings

FIG. 1 is an overall structure diagram of the present invention;

FIG. 2 is a partial internal structure view of the present invention;

fig. 3 is a wiring diagram of the present invention.

In the figure: 1. a tester suitcase; 11. a PCB board; 12. a switch; 2. a control panel; 21. a display screen; 22. three clamp meter current interfaces; 3. a voltage clamp; 4. secondary clamp gauges; 5. a zero line clamp; 6. and the current transformer to be tested.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In order to solve the problem that in the prior art, a common online low-voltage CT transformation ratio tester needs to completely surround a cable or a busbar with a large-size open type current caliper or a flexible current coil to test primary current, but the clamping difficulty is very high when a primary current carrier is a copper bar, the operation difficulty is higher particularly in a place with narrow busbar spacing, and transformation ratio measurement cannot be realized even. In addition, the conventional transformation ratio tester mainly measures according to the field load current, when the field load current is small, the measurement precision is extremely low, even an error result occurs, the following technical scheme is provided, please refer to fig. 1-3;

a characteristic current increment type low-voltage CT transformation ratio tester comprises a tester suitcase 1, wherein a control panel 2 is arranged in the tester suitcase 1, the control panel 2 cuts off one side of the tester suitcase 1 and closes a control cavity, a PCB 11 and a switch 12 are arranged in the control cavity, and the PCB 11 and the switch 12 are connected through a lead;

a slot hole for inserting the switch 12 is formed in the control panel 2, a display screen 21 and a three-way clamp meter current interface 22 are further arranged on the control panel 2, and the three-way clamp meter current interface 22 is respectively connected with the voltage wire clamp 3, the secondary clamp meter 4 and the zero wire clamp 5;

the voltage wire clamp 3 is connected to an exposed conducting point on the side of an outgoing line P2 of the current transformer 6 to be tested, characteristic current can be injected, the characteristic current with certain amplitude and time domain characteristics is actively injected into primary background current, and the characteristic current is simultaneously superposed into secondary current through the CT to be tested according to transformation ratio parameter transformation;

the secondary clamp meter 4 is connected with a secondary outgoing line of the tested current transformer 6, a resultant current obtained by superposing a background current and a characteristic current is induced on the secondary outgoing line connected with the tested current transformer 6, and the current is converted into a voltage signal through an electronic circuit in the tester and is acquired and processed;

the zero line clamp 5 is connected to the zero line or the exposed conducting point of the zero row to provide a characteristic current path.

The display screen 21 and the three clamp meter current interface 22 are respectively connected to the PCB 11 through wires.

Screw holes are formed in four end corners of the control panel 2, studs are arranged at four ends of the tester suitcase 1, and bolts penetrating through the screw holes of the control panel 2 are meshed with the studs.

The tester suitcase 1 comprises a box body and a cover plate, wherein the box body is connected with the cover plate through a hinge, and the control panel 2 is flush with the opening of the box body. And a secondary outlet of the tested current transformer 6 is used for connecting a three-phase line and a single-line or three-phase load.

Specifically, tester suitcase 1 is convenient to be opened through the mode of hinge to tester suitcase 1 opens the back, controls panel 2 and directly reveals, and the operator can directly use, and three routes clamp meter current interface 22 passes through plug-in connection voltage fastener 3, secondary clamp meter 4 and zero line fastener 5, lets its assembly method simple quick.

In summary, the following steps: this characteristic current increment formula low pressure CT transformation ratio tester, one wiring through the fastener joint by the survey current transformer 6 go out the exposed live point of line side can, totally not restricted by box space and female interval of arranging, the joint is very convenient, has very big advantage, the measuring method of initiative injection type does not receive load current's influence totally, load light load, heavy load all can draw accurate result.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (5)

1. A characteristic current increment type low-voltage CT transformation ratio tester comprises a tester suitcase (1) and is characterized in that a control panel (2) is arranged in the tester suitcase (1), the control panel (2) cuts off one side of the tester suitcase (1) and closes a control cavity, a PCB (11) and a switch (12) are arranged in the control cavity, and the PCB (11) and the switch (12) are connected through a lead;

a slotted hole for inserting the switch (12) is formed in the control panel (2), a display screen (21) and three clamp meter current interfaces (22) are further arranged on the control panel (2), and the three clamp meter current interfaces (22) are respectively connected with a voltage wire clamp (3), a secondary clamp meter (4) and a zero wire clamp (5);

the voltage wire clamp (3) is connected to an exposed conducting point on the side of an outgoing line P2 of the tested current transformer (6);

the secondary split-core type ammeter (4) is connected to a secondary outgoing line of the tested current transformer (6);

the zero line clamp (5) is connected with the exposed conducting point of the zero line or the zero row.

2. The incremental low-voltage CT transformation ratio tester for testing the CT according to claim 1, wherein the display screen (21) and the three clamp meters (22) are respectively connected to the PCB (11) through wires.

3. The characteristic current increment type low-voltage CT transformation ratio tester as claimed in claim 1, wherein the four corners of the control panel (2) are provided with screw holes, the four ends of the tester suitcase (1) are provided with studs, and the bolts penetrating through the screw holes of the control panel (2) are engaged with the studs.

4. A characteristic current increment type low voltage CT transformation ratio tester according to claim 1, wherein the tester suitcase (1) comprises a box body and a cover plate, the box body and the cover plate are connected through a hinge, and the operation panel (2) is flush with the opening of the box body.

5. A characteristic current increment type low-voltage CT transformation ratio tester according to claim 1, wherein the secondary outlet of the tested current transformer (6) is used for connecting three-phase wires and single-wire or three-phase loads.

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