CN107329008B - Phase sequence detection circuit - Google Patents
Phase sequence detection circuit Download PDFInfo
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- CN107329008B CN107329008B CN201710534579.3A CN201710534579A CN107329008B CN 107329008 B CN107329008 B CN 107329008B CN 201710534579 A CN201710534579 A CN 201710534579A CN 107329008 B CN107329008 B CN 107329008B
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- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
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Abstract
The invention relates to a phase sequence detection circuit, which comprises: two contactors KM1 and KM2, three switch buttons SA, NA and TA, an air switch QF with a thermocouple, three voltmeters V1, V2 and V3, a clockwise phase-sequence indicator lamp HD, a counterclockwise phase-sequence indicator lamp LD and three sets of terminals P1, P2 and P3 for three-phase wiring of the phase-sequence meter; the phase sequence of alternating current can be conveniently and rapidly obtained by further detecting the phase sequence through the voltmeter and the phase sequence indicator lamp, meanwhile, the air switch QF is arranged, and if danger occurs, the power supply can be rapidly cut off, so that the operation safety is further enhanced.
Description
Technical Field
The invention relates to the technical field of phase sequence detection, in particular to a phase sequence detection circuit.
Background
At present, a A, B, C three-phase power supply is led out from an alternating-current 380V power supply by adopting a lead wire for detecting the phase sequence of the three-phase power supply, the three phases of a phase sequence table are respectively connected with corresponding three-phase lead wires A, B, C, whether the phase sequence table rotates positively or not is observed, then two phases are selected at will from the three phases of the phase sequence table, the lead wires are exchanged, and whether the phase sequence table rotates reversely or not is observed, so that whether the phase sequence table is good or not is determined; the operation is complex, the short circuit or the grounding of the alternating current 380V three-phase power supply is easy to cause, the instrument is damaged, and the safety accident is caused.
Disclosure of Invention
The invention provides a phase sequence detection circuit for solving the defects of complex operation, low safety and the like in the prior art.
In order to solve the technical problems, the invention adopts the following technical scheme:
a phase sequence detection circuit, said detection circuit comprising: two contactors KM1 and KM2, three switch buttons SA, NA and TA, an air switch QF with a thermocouple, three voltmeters V1, V2 and V3, a clockwise phase-sequence indicator lamp HD, a counterclockwise phase-sequence indicator lamp LD and three sets of terminals P1, P2 and P3 for connection with the phase-sequence meter;
the air switch QF comprises four protection switches K1-K4; one end of the protection switch K1-K3 is sequentially connected with three-phase three-line L1, L2 and L3; one end of the switch K4 is connected with a neutral line N of three phases;
the other ends of the protection switches K1-K3 are sequentially connected with binding posts P1, P2 and P3 through normally open contact groups KM 1.3; the other ends of the protection switches K1-K3 are sequentially connected with binding posts P1, P2 and P3 through normally open contact sets KM 2.3;
one end of each of the voltmeters V1, V2 and V3 is connected with the other end of the protection switch K4; the other ends of the voltmeters V1, V2 and V3 are sequentially connected with the binding posts P1, P2 and P3;
one end of the clockwise phase sequence indicator lamp HD is connected with the other end of the protection switch K1 through a normally open contact KM 1.4; the other end of the clockwise phase sequence indicator lamp HD is connected with the other end of the protection switch K4;
one end of the anticlockwise phase sequence indicator lamp LD is connected with the other end of the protection switch K1 through a normally open contact KM 2.4; the other end of the anticlockwise phase sequence indicator lamp LD is connected with the other end of the protection switch K4;
one end of the contactor KM1 is connected with one end of a switch button TA through a normally closed contact KM 2.2; the other end of the contactor KM1 is connected with the other end of the protection switch K1 through a normally open contact KM 1.1; the other end of the contactor KM1 is connected with one end of a switch button SA;
the other end of the switch button SA is connected with the other end of the protection switch K1; the other end of the switch button TA is connected with the other end of the protection switch K4;
one end of the contactor KM2 is connected with one end of a switch button TA through a normally closed contact KM 1.2; the other end of the contactor KM2 is connected with the other end of the protection switch K1 through a normally open contact KM 2.1; the other end of the contactor KM2 is connected with one end of a switch button NA;
the other end of the switch button NA is connected with the other end of the protection switch K1.
The working principle of the scheme is as follows: in order to prevent safety accidents, an air switch QF is arranged, and if short circuit or electric shock danger occurs, the air switch QF can rapidly cut off a power supply to prevent accidents; when detection is needed, 380V three-phase alternating current is communicated for the three lines L1, L2 and L3; the voltage values of the inspection voltage tables V1, V2, and V3 are all shown as 0V; connecting Q1 of the phase sequence table with the binding post P1, Q2 of the phase sequence table with the binding post P2, and Q3 of the phase sequence table with the binding post P3;
when the clockwise phase sequence needs to be detected, the switch button SA is pressed, and the current direction of the first loop is as follows:
l1→closing of the protection switch K1→node 2→conduction of the switch button sa→conduction of the contactor KM1→km2.2→conduction of the switch button ta→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the contactor KM1 is excited, the normally open contact KM1.1, the normally open contact set KM1.3 and the normally open contact KM1.4 are closed, and the normally closed contact KM1.2 is opened;
since the normally open contact KM1.1 is closed, the current direction of the second loop is as follows:
l1→closing of the protection switch K1→node 2→km1.1→contactor KM1→km2.2→switching button TA conduction→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the second loop is conducted, and the normally open node KM1.1 realizes self-holding;
the normally open contact KM1.4 is closed and the direction of the third loop is as follows:
l1→closing of the protection switch K1→node 2→km1.4→clockwise phase sequence indicator lamp hd→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the clockwise phase sequence indicator lamp HD becomes bright, and the phase sequence detection circuit outputs a clockwise phase sequence power supply; at this time, as the normally open contact group KM1.3 is closed, the voltages displayed by the voltmeters V1, V2 and V3 are all 220V of alternating current, and the phase sequence detection circuit outputs a normal power supply with a clockwise phase sequence, wherein the normally closed contact KM1.2 is opened at this time, so as to prevent the simultaneous pressing of the switch button SA and the switch button NA, which leads to the simultaneous excitation of the contactors KM1, KM2 and the short circuit of the phase sequence detection circuit; at this time, the phase sequence table should display clockwise rotation, and then the detection is normal; after the detection is finished, the switch button TA is pressed down, so that the contactor KM1 loses magnetism, the normally open contact group KM1.3 is disconnected, the phase sequence detection circuit does not output voltage, and the voltmeters V1, V2 and V3 are all 0V;
when the anticlockwise phase sequence needs to be detected, the switch button NA is pressed, and the direction of the fourth loop is as follows:
l1→closing of the protection switch K1→node 2→conduction of the switch button na→km2→km1.2→conduction of the switch button ta→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the contactor KM2 is excited, the normally open contact KM2.1, the normally open contact set KM1.3 and the normally open contact KM2.4 are closed, and the normally closed contact KM2.2 is opened;
since the normally open contact KM2.1 is closed, the direction of the fifth loop is as follows:
l1→closing of the protection switch K1→node 2→km2.1→contactor KM2→km1.2→switching button TA conduction→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the fifth loop is conducted, and the normally open node KM2.1 realizes self-holding;
the normally open contact KM2.4 is closed and the direction of the sixth loop is as follows:
l1→closing of the protection switch K1→node 2→km2.4→anticlockwise phase sequence indicator lamp ld→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the counter-clockwise phase-sequence indicator lamp LD becomes bright, and the phase-sequence detection circuit outputs a power supply of counter-clockwise phase sequence; at this time, as the normally open contact group KM2.3 is closed, the voltages displayed by the voltmeters V1, V2 and V3 are all 220V of alternating current, and the phase sequence detection circuit outputs a normal power supply with a counterclockwise phase sequence, wherein the normally closed contact KM2.2 is opened at this time, so as to prevent the simultaneous pressing of the switch button SA and the switch button NA, which leads to the simultaneous excitation of the contactors KM1, KM2 and the short circuit of the phase sequence detection circuit; at this time, the phase sequence table should display counterclockwise rotation, and then indicates that the detection is normal; after the detection is finished, the switch button TA is pressed down, so that the contactor KM2 loses magnetism, the normally open contact group KM2.3 is disconnected, no output voltage is generated in the phase sequence, and the voltmeters V1, V2 and V3 are all 0V.
In the scheme, the voltmeter and the phase sequence indicator lamp are adopted to further detect the phase sequence, the phase sequence of alternating current can be conveniently and rapidly obtained, meanwhile, the air switch QF is installed, if danger occurs, the power supply can be rapidly cut off, and the operation safety is further enhanced.
Preferably, the terminal P1 includes a plurality of terminals; the binding post P2 comprises a plurality of binding terminals; the post P3 includes a plurality of terminals.
Preferably, the phase sequence detection circuit is installed in a fireproof and insulating shell.
Preferably, the identification colors of the switch buttons SA, NA and TA are red, green and black respectively.
Compared with the prior art, the invention has the beneficial effects that: according to the technical scheme, the phase sequence of alternating current can be conveniently and rapidly obtained by further detecting the phase sequence through the voltmeter and the phase sequence indicator lamp, meanwhile, the air switch QF is arranged, and if danger occurs, the power supply can be rapidly cut off, so that the operation safety is further enhanced.
Drawings
Fig. 1 is a schematic diagram of a phase sequence detection circuit according to the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made with reference to the accompanying drawings, in which it is evident that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
A schematic diagram of a phase sequence detection circuit is shown in fig. 1: the device comprises two contactors KM1 and KM2, three switch buttons SA, NA and TA, an air switch QF with a thermocouple, three voltmeters V1, V2 and V3, a clockwise phase sequence indicator lamp HD, a anticlockwise phase sequence indicator lamp LD and three groups of binding posts P1, P2 and P3 used for being connected with the phase sequence meter;
the air switch QF comprises four protection switches K1-K4; one end of the protection switch K1-K3 is sequentially connected with three-phase three-line L1, L2 and L3; one end of the switch K4 is connected with a neutral line N of three phases;
the other ends of the protection switches K1-K3 are sequentially connected with binding posts P1, P2 and P3 through normally open contact groups KM 1.3; the other ends of the protection switches K1-K3 are sequentially connected with binding posts P1, P2 and P3 through normally open contact sets KM 2.3;
one end of each of the voltmeters V1, V2 and V3 is connected with the other end of the protection switch K4; the other ends of the voltmeters V1, V2 and V3 are sequentially connected with the binding posts P1, P2 and P3;
one end of the clockwise phase sequence indicator lamp HD is connected with the other end of the protection switch K1 through a normally open contact KM 1.4; the other end of the clockwise phase sequence indicator lamp HD is connected with the other end of the protection switch K4;
one end of the anticlockwise phase sequence indicator lamp LD is connected with the other end of the protection switch K1 through a normally open contact KM 2.4; the other end of the anticlockwise phase sequence indicator lamp LD is connected with the other end of the protection switch K4;
one end of the contactor KM1 is connected with one end of a switch button TA through a normally closed contact KM 2.2; the other end of the contactor KM1 is connected with the other end of the protection switch K1 through a normally open contact KM 1.1; the other end of the contactor KM1 is connected with one end of a switch button SA;
the other end of the switch button SA is connected with the other end of the protection switch K1; the other end of the switch button TA is connected with the other end of the protection switch K4;
one end of the contactor KM2 is connected with one end of a switch button TA through a normally closed contact KM 1.2; the other end of the contactor KM2 is connected with the other end of the protection switch K1 through a normally open contact KM 2.1; the other end of the contactor KM2 is connected with one end of a switch button NA;
the other end of the switch button NA is connected with the other end of the protection switch K1.
In this embodiment, in order to prevent a safety accident, an air switch QF is installed, and if a short circuit or an electric shock hazard occurs, the air switch QF can rapidly cut off the power supply to prevent the accident; when detection is needed, 380V three-phase alternating current is communicated for the three lines L1, L2 and L3; the voltage values of the inspection voltage tables V1, V2, and V3 are all shown as 0V; connecting Q1 of the phase sequence table with the binding post P1, Q2 of the phase sequence table with the binding post P2, and Q3 of the phase sequence table with the binding post P3;
when the clockwise phase sequence needs to be detected, the switch button SA is pressed, and the current direction of the first loop is as follows:
l1→closing of the protection switch K1→node 2→conduction of the switch button sa→conduction of the contactor KM1→km2.2→conduction of the switch button ta→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the contactor KM1 is excited, the normally open contact KM1.1, the normally open contact set KM1.3 and the normally open contact KM1.4 are closed, and the normally closed contact KM1.2 is opened;
since the normally open contact KM1.1 is closed, the current direction of the second loop is as follows:
l1→closing of the protection switch K1→node 2→km1.1→contactor KM1→km2.2→switching button TA conduction→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the second loop is conducted, and the normally open node KM1.1 realizes self-holding;
the normally open contact KM1.4 is closed and the direction of the third loop is as follows:
l1→closing of the protection switch K1→node 2→km1.4→clockwise phase sequence indicator lamp hd→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the clockwise phase sequence indicator lamp HD becomes bright, and the phase sequence detection circuit outputs a clockwise phase sequence power supply; at this time, as the normally open contact group KM1.3 is closed, the voltages displayed by the voltmeters V1, V2 and V3 are all 220V of alternating current, and the phase sequence detection circuit outputs a normal power supply with a clockwise phase sequence, wherein the normally closed contact KM1.2 is opened at this time, so as to prevent the simultaneous pressing of the switch button SA and the switch button NA, which leads to the simultaneous excitation of the contactors KM1, KM2 and the short circuit of the phase sequence detection circuit; at this time, the phase sequence table should display clockwise rotation, and then the detection is normal; after the detection is finished, the switch button TA is pressed down, so that the contactor KM1 loses magnetism, the normally open contact group KM1.3 is disconnected, the phase sequence detection circuit does not output voltage, and the voltmeters V1, V2 and V3 are all 0V;
when the anticlockwise phase sequence needs to be detected, the switch button NA is pressed, and the direction of the fourth loop is as follows:
l1→closing of the protection switch K1→node 2→conduction of the switch button na→km2→km1.2→conduction of the switch button ta→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the contactor KM2 is excited, the normally open contact KM2.1, the normally open contact set KM1.3 and the normally open contact KM2.4 are closed, and the normally closed contact KM2.2 is opened;
since the normally open contact KM2.1 is closed, the direction of the fifth loop is as follows:
l1→closing of the protection switch K1→node 2→km2.1→contactor KM2→km1.2→switching button TA conduction→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the fifth loop is conducted, and the normally open node KM2.1 realizes self-holding;
the normally open contact KM2.4 is closed and the direction of the sixth loop is as follows:
l1→closing of the protection switch K1→node 2→km2.4→anticlockwise phase sequence indicator lamp ld→node 3→node 1→closing of the protection switch K4→neutral line N;
at this time, the counter-clockwise phase-sequence indicator lamp LD becomes bright, and the phase-sequence detection circuit outputs a power supply of counter-clockwise phase sequence; at this time, as the normally open contact group KM2.3 is closed, the voltages displayed by the voltmeters V1, V2 and V3 are all 220V of alternating current, and the phase sequence detection circuit outputs a normal power supply with a counterclockwise phase sequence, wherein the normally closed contact KM2.2 is opened at this time, so as to prevent the simultaneous pressing of the switch button SA and the switch button NA, which leads to the simultaneous excitation of the contactors KM1, KM2 and the short circuit of the phase sequence detection circuit; at this time, the phase sequence table should display counterclockwise rotation, and then indicates that the detection is normal; after the detection is finished, the switch button TA is pressed down, so that the contactor KM2 loses magnetism, the normally open contact group KM2.3 is disconnected, no output voltage is generated in the phase sequence, and the voltmeters V1, V2 and V3 are all 0V.
In this embodiment, adopted voltmeter and phase sequence pilot lamp further to detect the phase sequence, but convenient and fast acquires the phase sequence of alternating current, simultaneously, installed air switch QF, can cut off the power rapidly when dangerous if taking place, further strengthen the security of operation.
In the present embodiment, the post P1 includes ten terminals; the post P2 includes ten terminals; the post P3 includes ten terminals.
In this embodiment, the phase sequence detection circuit is mounted in a fire-proof and insulating housing.
In the present embodiment, the identification colors of the switch buttons SA, NA, and TA are red, green, and black, respectively.
It is to be understood that the above examples of the present invention are provided by way of illustration only and not by way of limitation of the embodiments of the present invention. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the invention are desired to be protected by the following claims.
Claims (2)
1. A phase sequence detection circuit, characterized by:
the detection circuit includes: two contactors KM1 and KM2, three switch buttons SA, NA and TA, an air switch QF with a thermocouple, three voltmeters V1, V2 and V3, a clockwise phase-sequence indicator lamp HD, a counterclockwise phase-sequence indicator lamp LD and three sets of terminals P1, P2 and P3 for connection with the phase-sequence meter;
the air switch QF comprises four protection switches K1-K4; one end of the protection switch K1-K3 is sequentially connected with three-phase three-line L1, L2 and L3; one end of the switch K4 is connected with a neutral line N of three phases;
the other ends of the protection switches K1-K3 are sequentially connected with binding posts P1, P2 and P3 through normally open contact groups KM 1.3; the other ends of the protection switches K1-K3 are sequentially connected with binding posts P1, P2 and P3 through normally open contact sets KM 2.3;
one end of each of the voltmeters V1, V2 and V3 is connected with the other end of the protection switch K4; the other ends of the voltmeters V1, V2 and V3 are sequentially connected with the binding posts P1, P2 and P3;
one end of the clockwise phase sequence indicator lamp HD is connected with the other end of the protection switch K1 through a normally open contact KM 1.4; the other end of the clockwise phase sequence indicator lamp HD is connected with the other end of the protection switch K4;
one end of the anticlockwise phase sequence indicator lamp LD is connected with the other end of the protection switch K1 through a normally open contact KM 2.4; the other end of the anticlockwise phase sequence indicator lamp LD is connected with the other end of the protection switch K4;
one end of the contactor KM1 is connected with one end of a switch button TA through a normally closed contact KM 2.2; the other end of the contactor KM1 is connected with the other end of the protection switch K1 through a normally open contact KM 1.1; the other end of the contactor KM1 is connected with one end of a switch button SA;
the other end of the switch button SA is connected with the other end of the protection switch K1; the other end of the switch button TA is connected with the other end of the protection switch K4;
one end of the contactor KM2 is connected with one end of a switch button TA through a normally closed contact KM 1.2; the other end of the contactor KM2 is connected with the other end of the protection switch K1 through a normally open contact KM 2.1;
the other end of the contactor KM2 is connected with one end of a switch button NA; the other end of the switch button NA is connected with the other end of the protection switch K1;
the binding post P1 comprises a plurality of binding terminals; the binding post P2 comprises a plurality of binding terminals; the binding post P3 comprises a plurality of binding terminals;
the phase sequence detection circuit is arranged in a fireproof and insulating shell.
2. The phase sequence detection circuit of, wherein: the identification colors of the switch buttons SA, NA and TA are red, green and black respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710534579.3A CN107329008B (en) | 2017-07-03 | 2017-07-03 | Phase sequence detection circuit |
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|---|---|---|---|
| CN201710534579.3A CN107329008B (en) | 2017-07-03 | 2017-07-03 | Phase sequence detection circuit |
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| CN107329008A CN107329008A (en) | 2017-11-07 |
| CN107329008B true CN107329008B (en) | 2023-05-05 |
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| CN109839547B (en) * | 2017-11-24 | 2024-01-30 | 深圳市蓝海华腾技术股份有限公司 | Three-phase power phase sequence detection circuit |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103595037A (en) * | 2013-10-22 | 2014-02-19 | 澳柯玛股份有限公司 | Three-phase alternating current phase sequence error correction device |
| CN106253212A (en) * | 2016-08-24 | 2016-12-21 | 国网山东省电力公司单县供电公司 | A kind of lack zero, phase shortage, phase sequence mistake power-off protection apparatus |
| CN106291141A (en) * | 2016-08-30 | 2017-01-04 | 中国能源建设集团江苏省电力建设第工程有限公司 | Job site three-phase power supply phase sequence automatic identification equipment |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8462471B2 (en) * | 2007-09-30 | 2013-06-11 | Huadao Huang | Circuit interrupting device with high voltage surge protection |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103595037A (en) * | 2013-10-22 | 2014-02-19 | 澳柯玛股份有限公司 | Three-phase alternating current phase sequence error correction device |
| CN106253212A (en) * | 2016-08-24 | 2016-12-21 | 国网山东省电力公司单县供电公司 | A kind of lack zero, phase shortage, phase sequence mistake power-off protection apparatus |
| CN106291141A (en) * | 2016-08-30 | 2017-01-04 | 中国能源建设集团江苏省电力建设第工程有限公司 | Job site three-phase power supply phase sequence automatic identification equipment |
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