CN210690785U - Portable direct current grounding test rapid testing device - Google Patents
Portable direct current grounding test rapid testing device Download PDFInfo
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- CN210690785U CN210690785U CN201921093169.0U CN201921093169U CN210690785U CN 210690785 U CN210690785 U CN 210690785U CN 201921093169 U CN201921093169 U CN 201921093169U CN 210690785 U CN210690785 U CN 210690785U
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- 238000012360 testing method Methods 0.000 title claims abstract description 48
- 238000005259 measurement Methods 0.000 claims description 18
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 14
- 229910052744 lithium Inorganic materials 0.000 claims description 14
- 239000002344 surface layer Substances 0.000 claims description 2
- 238000001514 detection method Methods 0.000 abstract description 15
- 238000012544 monitoring process Methods 0.000 abstract 1
- 238000006243 chemical reaction Methods 0.000 description 6
- 230000001105 regulatory effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 239000000428 dust Substances 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 1
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- 230000002035 prolonged effect Effects 0.000 description 1
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Abstract
The utility model discloses a quick testing arrangement of portable direct current ground test. In order to overcome the problem of single function of the portable direct current grounding detection device in the prior art, the portable direct current grounding detection device adopts a box body with a portable handle, and a user operation panel and an internal test circuit are arranged in the box body; the user operation panel is provided with an input port, an output port, a measuring meter, a selection switch, an analog resistance interface, a resistance adjusting part and an external charging port; the internal test circuit comprises an alternating current output circuit, a power supply circuit, a direct current output circuit and a direct current grounding analog resistance circuit, wherein the input end of the alternating current output circuit, the power supply circuit and the direct current output circuit are respectively connected with the input port. The device is portable, monitoring points can be conveniently brought, functions are rich and complete, the measuring modes are multiple, the measuring range is wide, the measuring data are accurate and various, and errors caused by manual reading are avoided.
Description
Technical Field
The utility model relates to a direct current ground test device especially relates to a quick testing arrangement of portable direct current ground test.
Background
The direct current power supply system is a low-voltage direct current uninterrupted power supply system which provides power for various control equipment in a station, such as a circuit breaker, a relay protection device, an automatic device and other primary and secondary equipment in a power system transformer substation; when the direct current grounding occurs in the direct current system, the safe operation of the control equipment is seriously influenced, the misoperation of the control equipment and the like can be caused, and the direct current grounding needs to be found and eliminated in time; in order to detect the ground insulation condition of the direct current system, the transformer substation is provided with a direct current insulation detection device.
In order to quickly and simply test a multipoint direct-current grounding fault point, a direct-current grounding device is usually arranged in a box body, but a common portable direct-current grounding test device is simple and portable, and has a single function and a limited application range. For example, a "dc grounding detection device for transformer substation" disclosed in chinese patent literature, which is disclosed under the publication number "CN 106707083A", includes a box, a dc air switch located inside the box, an input module, an output module, a voltmeter module and a fixing device, wherein the voltmeter module includes a first voltmeter module and a second voltmeter module, an output end of the input module is connected to an input end of the first voltmeter module, an output end of the first voltmeter module is connected to the dc air switch, the dc air switch is connected to an input end of the second voltmeter module, an output end of the second voltmeter module is connected to the output module, the output module is connected to the fixing device, and the fixing device includes a binding post and a fastening bolt for fastening and connecting a test line. The device is simple and portable, but the internal circuit is simple, the function is single, and the application range is limited.
SUMMERY OF THE UTILITY MODEL
The utility model mainly solves the problems that the prior art has the portable function of the direct current grounding detection device, but has single function, limited application range and the like; the portable direct-current grounding test rapid testing device not only can be portable, but also has complete and rich functions and wide application range.
The above technical problem of the present invention can be solved by the following technical solutions:
the utility model comprises a box body with a handle, the box body comprises a content box and a cover plate box which can cover the content box, the surface layer of the content box is provided with a user operation panel, the interior of the content box is provided with a test circuit, and the test circuit is correspondingly connected with the operation panel; the user operation panel is provided with a selection area, an adjustment display area and a measurement output area; the selection area comprises an input port and a selection switch, the adjustment display area comprises a measuring meter, a resistance adjusting part and an external charging port, and the measurement output area comprises an output port, a measuring meter and an analog resistance interface; the internal test circuit comprises an alternating current output circuit, a power supply circuit, a direct current output circuit and a direct current grounding analog resistance circuit, wherein the input end of the alternating current output circuit, the power supply circuit and the direct current output circuit are respectively connected with the input port. The direct current grounding detection device is arranged in a box body with a handle, can be carried by hand, is convenient to carry, and can be conveniently brought to each direct current detection point for detection; the box divide into apron case and content case, and the content case divide into top layer and inside, and the top layer sets up operating panel, and inside sets up test circuit, test circuit and operating panel one-to-one, and the apron case of box can cover and close on the content case, prevents that the dust from getting into. In addition, the user operation panel function is complete with the table meter, can accurately obtain each parameter, and the cooperation is inside detection circuitry, and the function is complete abundant, and the circuit has direct current output and exchanges two kinds of modes of output, and the test mode is various, and the range of application is extensive.
Preferably, the output port comprises an alternating current output port and a direct current output port. The device is provided with an alternating current/direct current output port, can be used for testing in an alternating current mode or a direct current mode, measures direct current and alternating current data, and has two measuring modes, namely, a measurable object range is enlarged.
Preferably, the measuring meter comprises an ammeter, a voltmeter and an ohmmeter. The measuring meter is provided with a plurality of ammeters, voltmeter and ohmmeters, is complete, can obtain complete data during direct-current grounding detection, and comprehensively analyzes the insulation condition of a line; and the number of the measuring meters is large, and corresponding meters are respectively arranged in different internal measuring circuits, so that disorder is avoided.
Preferably, the measuring meter is an electronic meter. Using an electronic meter, the data can be read by the controller as a data source for control; the LED of the connection of electron meter shows corresponding measurement value, makes things convenient for artifical reading, and data are more directly perceived, reduces the error on the data that artifical reading brought.
Preferably, the resistance adjustment unit includes a coarse adjustment unit and a fine adjustment unit. The coarse adjustment part of the resistor can expand the adjustment range of the resistor, so that the resistor can change between resistance values in a large range; the fine adjustment part of the resistor can accurately adjust the resistor, the test precision is enhanced, and when the balanced bridge is used for measurement, the resistance values of the two bridge arms are as close as possible.
Preferably, the selection switch comprises a function selection switch and a power selection switch. The power supply selection switch can be used for selecting the power supply mode of an internal circuit, a lithium battery is arranged in the circuit, the power supply selection switch can be used for supplying power to all parts of the circuit, an external power supply can be selected for supplying power, two power supply schemes are adopted, the power supply condition of the equipment is ensured, and the power supply selection switch is suitable for various use environments. The function selection switch can select different measurement functions during direct current measurement, is a single-pole three-throw switch, and has three state selections, namely resistance output, voltage measurement and resistance output functions.
Preferably, the alternating current output circuit comprises a voltage regulator and a transformer which are connected in sequence, the output end of the transformer is respectively connected with the first end of the protective resistor R3 and the first end of the relay K1, the second end of the protective resistor R3 and the second end of the relay K1 are used as alternating current output ends, and a voltmeter V0 is connected between the two ends. The voltage of commercial power frequency is output, the output voltage is adjusted by the autotransformer, the voltage is output through the isolation transformer, the current is limited and protected through the protection resistor, the relay K1 is controlled to output through the output button and the cutting button, and the output voltage is displayed by the digital voltmeter.
Preferably, the dc-to-ground analog resistance part comprises a switch S2, an overcurrent protection relay K2, a fuse FU, a coarse adjusting resistor R1, a fine adjusting resistor R2, an ammeter a, and a voltmeter V and an ohmmeter Ω connected to two ends of the dc-to-ground analog resistance part, which are connected in sequence. The function selection switch selects the function used by the analog resistor part, the overcurrent protection relay and the fuse protection circuit are safe, the resistance value in the adjustable resistor adjusting loop is adjusted, and the meter measures related data. When the resistance output is selected, the voltmeter measures the voltage at two ends of the analog resistance part, and the ammeter measures the current in the resistance; when the voltage measurement is selected, the resistance loop is disconnected, and the voltmeter measures the voltage at two ends of the analog resistance part; when "resistance measurement" is selected, the ohmmeter measures the resistance in the resistance loop.
Preferably, the direct current output circuit comprises an adjustable switching power supply, and a voltmeter V1 and an ammeter A1 which are arranged at the output end of the switching power supply. The switch power supply is an AD/DC switch power supply, alternating current of commercial power is input, regulated direct current voltage is output, the output voltage is regulated and regulated by using the multi-surface potentiometer, and the voltmeter and the ammeter can display the output voltage and current.
Preferably, the power supply circuit comprises a lithium battery and an external charging port, a first end of the lithium battery is connected with a first end of the external charging port, and a second end of the lithium battery and a second end of the external charging port are respectively connected with two contacts of the switch S1. The output of the power supply circuit supplies power for the meter of the equipment, the built-in lithium battery supplies power for the meter under the condition that no commercial power is input, and the duration time is more than or equal to 8 hours. Under the condition of selecting "commercial power supply", the commercial power passes through AD/DC conversion module and converts into the direct current, for the table meter power supply, and the lithium cell can charge through external charging mouth.
The utility model has the advantages that:
1. the measuring device is arranged in the box with the portable handle, is convenient to carry and carry, and can be brought to each measuring point.
2. The device has the advantages of alternating current and direct current output, wide application range, two measurement modes and various measurement modes.
3. The power supply of the equipment is ensured by using the power supply of the built-in lithium battery and the power supply of the external power supply.
4. The device has the functions of resistance output, voltage measurement, resistance measurement and the like, and is rich and complete in function.
5. The electronic measuring meter is used, measuring data are complete and various, reading and control are facilitated, and errors caused by manual reading are avoided.
Drawings
Fig. 1 is a schematic structural view of the present invention;
fig. 2 is a schematic diagram of a circuit principle structure of the present invention;
fig. 3 is a circuit diagram of a dc ground analog resistor according to the present invention.
In the figure, 1, an input port, 21, an alternating current output port, 22, a direct current output port, 3, a measuring meter, 41, a function selection switch, 42, a power supply selection switch, 5, an analog resistor interface, 61, a coarse adjustment part, 62, a fine adjustment part, 7, an alternating current output circuit, 71, a voltage regulator, 72, a transformer, 8 a power supply circuit, 81, an AD/DC conversion module, 82, an external charging port, 83, a lithium battery, 9, a direct current output circuit and 91 are switched on and off.
Detailed Description
The technical solution of the present invention is further specifically described below by way of examples and with reference to the accompanying drawings.
Example (b):
the portable direct-current grounding test rapid testing device of the embodiment comprises a box body with a portable handle, as shown in fig. 1, wherein the box body comprises a content box and a cover plate box which is connected with the content box through a hinge and can be covered on the content box, an operation panel operated by a user is additionally arranged on the surface of the content box, and a detection circuit is arranged inside the content box; the cover plate box is provided with a hook-shaped lock which can be locked with the content box when the cover plate box is closed, and the carrying handle is arranged on the outer surface of the content box. The direct-current grounding detection device is arranged in a box body, and a hand-held handle is arranged on the box body, so that the direct-current grounding detection device is convenient for workers to carry, can easily carry the device to a detection point for detection, and is convenient to carry; the design has the apron case, can close when not using the lid, prevents that the dust from getting into.
On the left side of the operation panel operated by the user, an input port 1 and two single-pole, triple-throw function selection switches 41 are provided from top to bottom.
The right side part of the operation panel is provided with a digital alternating current voltmeter V0 display for detecting alternating current output voltage at the upper right corner, an alternating current output port 21 with two holes is arranged below the voltmeter V0, a direct current output port 22 is arranged below the voltmeter, and a digital direct current voltmeter V1 display for detecting direct current output voltage and a digital ammeter A1 display for detecting direct current output current are arranged below the output ports; two pairs of analog resistor interfaces 5 are arranged on the lower side, namely the lower right corner. The digital measuring meter 3 displays the measured value of the meter on the operation interface by a 4-bit LED.
A power supply selection switch 42 for controlling a power supply mode is arranged at the upper left corner of the middle part of the operation panel, and an external charging port 82 capable of being externally connected with a charger is arranged below the power supply selection switch 42; a coarse adjustment part 61 provided with two coarse adjustment resistors and a fine adjustment part 62 provided with two fine adjustment resistors are arranged below the middle part of the operation panel from left to right, and the coarse adjustment resistors R1 and the fine adjustment resistors R2 in the two-way direct current grounding analog resistor part in the circuit are respectively corresponding; and 4-bit LED displays of 6 digital measuring meters 3 are arranged above the resistance adjusting part, and are arranged in two rows, wherein 3 digital measuring meters are arranged in each row and respectively correspond to a voltmeter V, an ammeter A and an ohmmeter omega in a direct-current grounding analog resistance part in the circuit. The rectangular hollow part is arranged above the display LED, and the transformer 72 and the lithium battery 83 in the circuit part are exposed from the hollow part, so that the cost of the layout can be saved, the design feeling of the interface can be increased, the heat dissipation of the electronic element can be enhanced, and the service life can be prolonged.
The interface is arranged on the operation interface, so that the operation is simple, the functions are various, the direct current and alternating current environment can be applied by combining an internal circuit, the application range is wide, and the functions are rich and complete; the interface is provided with a plurality of measuring meters 3 which can measure various data in the circuit, and the measured data is complete and comprehensive and is not easy to be confused; the digital meter is convenient for workers to read, errors caused by manual reading can be avoided, and accuracy is guaranteed.
As shown in fig. 2, in the circuit diagram of the internal measurement circuit, ac commercial power is input from an input port 1, the input port 1 is connected to one end of a power switch S, and the other end of the power switch S is used as an input and is respectively input to an ac output circuit 7, a power supply circuit 8, and a dc output circuit 9.
The alternating current output circuit 7 comprises a voltage regulator 71 and a transformer 72 which are connected in sequence, wherein the input end of the voltage regulator 71 is connected to the second end of the power switch 2, the output end of the transformer is respectively connected with the first end of a relay K1 and the first end of a current-limiting resistor R3, and the second end of a relay K1 and the second end of a current-limiting resistor R3 are used as output ends and are respectively connected to an alternating current output port 21 of the operation interface; the two ends of the alternating current voltmeter V0 are connected to two output ends, and the voltage of the alternating current output is measured.
The power supply circuit 8 comprises an AD/DC conversion module 81, an input end of the AD/DC conversion module 81 is connected to a second end of a power switch S, a first output end of an output end of the AD/DC conversion module 81 is connected to a first end of an external charging port 82 and a lithium battery 83, a second output end is connected to a first contact of a power selection switch 42, a second contact of the power selection switch 42 is connected to a first contact of a switch S1, a second contact of a switch S1 is connected to a second end of the external charging port 82, a switch S1 is connected to the lithium battery 83, and the power selection switch 42 and the first output end of the AD/DC conversion module 81 are used together as output ends for supplying power to the measuring meter 3 in the circuit.
The direct current output circuit 9 comprises an AD/DC switching power supply 91, a voltmeter V1 and an ammeter a1, wherein an input end of the AD/DC switching power supply 91 receives alternating current commercial power, a multi-surface potentiometer is used for adjusting and regulating output direct current voltage, the output is used as an output end and is connected to a direct current output port 22 on an operation interface, two ends of the voltmeter V1 are respectively connected to an output end of the AD/DC switching power supply 91 to measure the voltage of the direct current output, and the ammeter a1 measures the current of the output direct current.
As shown in fig. 3, two ends of the dc ground analog resistor respectively correspond to the analog resistor interfaces 5 on the operation interface, and when in use, two sets are used as two arms of the balance bridge. The direct-current grounding analog resistor part comprises a switch S2, an overcurrent protection relay K2, a fuse FU, a coarse adjusting resistor R1, a fine adjusting resistor R2 and an ammeter A which are sequentially connected; the switch S2 is a single-pole triple-throw selector switch, a first contact of the switch S2 is connected with a first interface of the analog resistor interface 5, a second contact of the switch S2 is suspended, a third contact of the switch S2 is connected with a first end of an ohmmeter omega, a second end of the ohmmeter omega is connected with a second interface of the analog resistor interface 5, a first end of a voltmeter V is connected with the first contact of the switch S2, and a second end of the voltmeter V is connected with the second interface of the analog resistor interface 5. The two groups of switches S2 correspond to the function selection switches 41 on the operation interface; the adjusting parts of the two groups of coarse adjusting resistors R1 correspond to the coarse adjusting part 61 of the operation interface; the adjustment portions of the two sets of fine adjustment resistors R2 correspond to the fine adjustment portion 62 of the operator interface.
When switch S2 is in the first contact, in the "resistor out" state, voltmeter V measures the voltage across the first and second interfaces of analog resistor interface 5, and ammeter a measures the current flowing through the resistor.
When the switch S2 is at the second contact, in the "voltage measurement" state, the voltage between the first interface and the second interface of the analog resistance interface 5 is measured via the voltmeter V.
When the switch S2 is in the third contact, in the "resistance measurement" state, the ohmmeter Ω measures the resistance in the resistance loop.
The operation interface combination circuit has multiple practical functions, can measure different data, has wide application range, more abundant and complete functions, simple interface and simple operation.
Claims (10)
1.A portable direct current grounding test rapid testing device comprises a box body with a portable handle, and is characterized in that the box body comprises a content box and a cover plate box which can be covered on the content box, a user operation panel is arranged on the surface layer of the content box, a testing circuit is arranged inside the content box, and the testing circuit is correspondingly connected with the operation panel; the user operation panel is provided with a selection area, an adjustment display area and a measurement output area; the selection area comprises an input port (1) and a selection switch, the adjustment display area comprises a measuring meter (3), a resistance adjusting part and an external charging port (82), and the measurement output area comprises an output port, a measuring meter (3) and an analog resistance interface (5); the internal test circuit comprises an alternating current output circuit (7), a power supply circuit (8), a direct current output circuit (9) and a direct current grounding analog resistance circuit, wherein the input ends of the alternating current output circuit, the power supply circuit and the direct current output circuit are respectively connected with the input port (1).
2. A hand-held dc-to-earth test rapid test device according to claim 1, wherein said outlets comprise an ac outlet (21) and a dc outlet (22).
3. A portable dc-grounding test rapid tester as claimed in claim 1, characterized in that said meter (3) comprises an ammeter, a voltmeter and an ohmmeter.
4. A portable dc grounding test rapid test device according to claim 3, characterized in that said meter (3) is an electronic meter.
5. A portable dc-based rapid test device for grounding tests as claimed in claim 1, wherein said resistance adjustment portion comprises a coarse adjustment portion (61) and a fine adjustment portion (62).
6. A hand-held dc-to-earth test rapid test device according to claim 1, wherein said selection switch comprises a function selection switch (41) and a power selection switch (42).
7. The portable direct current grounding test rapid testing device according to claim 1, characterized in that the alternating current output circuit (7) comprises a voltage regulator (71) and a transformer (72) which are connected in sequence, the output end of the transformer (72) is respectively connected with the first end of a protection resistor R3 and the first end of a relay K1, the second end of the protection resistor R3 and the second end of the relay K1 are used as alternating current output ends, and a voltmeter V0 is connected between the two ends.
8. The portable direct-current grounding test rapid testing device as claimed in claim 1, wherein the direct-current grounding analog resistance part comprises a switch S2, an over-current protection relay K2, a fuse FU, a coarse adjusting resistor R1, a fine adjusting resistor R2 and an ammeter A which are connected in sequence, and a voltmeter V and an ohmmeter omega which are connected at two ends of the direct-current grounding analog resistance part.
9. The portable direct current grounding test rapid test device as claimed in claim 1, characterized in that the direct current output circuit (9) comprises an adjustable switching power supply (91) and a voltmeter V1 and an ammeter a1 which are arranged at the output terminal of the switching power supply (91).
10. The portable direct-current grounding test rapid testing device according to claim 1, characterized in that the power supply circuit (8) comprises a lithium battery (83) and an external charging port (82), a first end of the lithium battery (83) is connected with a first end of the external charging port (82), and a second end of the lithium battery (83) and a second end of the external charging port (82) are respectively connected with two contacts of a switch S1.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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CN201921093169.0U CN210690785U (en) | 2019-07-12 | 2019-07-12 | Portable direct current grounding test rapid testing device |
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CN201921093169.0U CN210690785U (en) | 2019-07-12 | 2019-07-12 | Portable direct current grounding test rapid testing device |
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CN210690785U true CN210690785U (en) | 2020-06-05 |
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CN201921093169.0U Expired - Fee Related CN210690785U (en) | 2019-07-12 | 2019-07-12 | Portable direct current grounding test rapid testing device |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112858951A (en) * | 2021-03-18 | 2021-05-28 | 浙江浙能嘉华发电有限公司 | Direct current system feeder grounding test device |
-
2019
- 2019-07-12 CN CN201921093169.0U patent/CN210690785U/en not_active Expired - Fee Related
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112858951A (en) * | 2021-03-18 | 2021-05-28 | 浙江浙能嘉华发电有限公司 | Direct current system feeder grounding test device |
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Granted publication date: 20200605 |