Portable low-voltage air switch comprehensive tester and use method thereof

Abstract

The application discloses a portable low-voltage air switch comprehensive tester and a use method thereof, and belongs to the field of power safety facilities. The portable low-voltage air switch comprehensive tester comprises a shell, an epoxy resin panel arranged in the shell, a leakage point test circuit and an overcurrent test circuit arranged on the panel, a short-circuit test device arranged in the shell, and the leakage point test circuit, the overcurrent test circuit and the short-circuit test device are respectively connected to a measured air switch and a 220V stabilized power supply line through a firewire and a zero line.

Description

Technical Field

[0001] The invention provides a portable low-voltage circuit breaker comprehensive tester and a use method thereof, belonging to the field of national power grid safety facilities. Background Art

[0002] Existing low-voltage AC circuit breakers (CCBs) are tested in separate instruments. There are specialized leakage testers (if the leakage current exceeds 30mA, the circuit breaker must trip reliably within 0.1s; if the leakage current is less than 15mA, the circuit breaker must not trip) and overcurrent testers (under the reference temperature specified in GB10963.1, for circuit breakers 63A and below, operation is prohibited at 1.13 times the rated current for one hour, and must then operate at 1.45 times the rated current within one hour). However, there are no specialized short-circuit testers. The common industry practice is to use the ends of insulating rods to fix the live and neutral wires on the load side of the circuit breaker with the circuit breaker closed, then directly contact them to create a short circuit. This creates large sparks and is quite dangerous. Therefore, power supply companies do not conduct short-circuit tests when accepting CCBs in meter boxes in newly built residential communities. This results in some substandard circuit breakers being connected to the grid, creating difficulties in subsequent operation and maintenance. When a short circuit occurs in a user's home appliance, the circuit breaker fails to operate or operates for a timeout, causing the main switch in the meter box to trip, leading to power outages for multiple households. Summary of the Invention

[0003] The purpose of the present invention is to provide a portable low-voltage circuit breaker comprehensive tester and its use method that can overcome the above-mentioned defects. It can test leakage, overcurrent and short circuit, and all are controlled by a remote control to avoid the risk of electric shock caused by human approach.

[0004] To achieve the above-mentioned purpose, the present invention provides a portable low-voltage circuit breaker comprehensive tester, comprising a shell, an epoxy resin panel provided inside the shell, and a leakage test circuit and an overcurrent test circuit provided on the panel; a short-circuit test device is provided inside the shell, and the leakage test circuit, overcurrent test circuit, and short-circuit test device are respectively connected to the circuit breaker to be tested and the 220V regulated power supply line through the live wire and the neutral wire.

[0005] Preferably, the leakage test circuit includes connecting a 6.3kΩ resistor and a remote control closing switch in series between the live wire and the ground wire, a 22kΩ resistor and the remote control closing switch in series and then connected in parallel with the 6.3kΩ resistor and the remote control closing switch; a power-on timer A is provided between the remote control closing switch and the neutral wire.

[0006] Preferably, the overcurrent test circuit includes a 3.09Ω resistor in series between the live wire and the neutral wire, the 3.09Ω resistor being in series with a 95A AC contactor I; a 2.408Ω resistor is also in series between the live wire and the neutral wire, the 2.408Ω resistor being in series with a 95A AC contactor II; the 2.408Ω resistor and the AC contactor II are in parallel with the 3.09Ω resistor and the AC contactor I, and the remote control switch is used to turn on and off the 220V AC power supply for the line circuit of the AC contactor I and the AC contactor II, and the power-on timer B is connected between the live wire and the neutral wire.

[0007] Preferably, the short-circuit test device includes a 12V electromagnet, the electromagnet is placed outside the shell, the electromagnet is connected with a telescopic rod, the end of the telescopic rod is inside the shell, a 10mm diameter carbon rod is sleeved in the epoxy tube and installed at the end of the telescopic rod, the end of the carbon rod is V-shaped, a V-shaped groove matching the end of the carbon rod is arranged in the shell, the back of the V-shaped groove is connected with one end of a spring, and the other end of the spring is connected with the shell.

[0008] Preferably, when the electromagnet is not powered, the distance between the carbon rod and the V-shaped groove is 8mm, and when the electromagnet is powered, the carbon rod extends forward by 12mm; the carbon rod is connected with the live wire by using a 2.5mm 2 soft copper wire; and the V-shaped groove is connected with the neutral wire by using a 2.5mm 2 soft copper wire.

[0009] Preferably, a first protection and a second protection are further arranged between the 220V stabilized power supply and the portable low-voltage air switch comprehensive tester, the first protection and the second protection are respectively a 95A air switch and a 100A RTO fuse.

[0010] A use method of a portable low-voltage air switch comprehensive tester is provided, including the following steps:

[0011] (1) Ground the instrument, install the connection of the 63A air switch to be tested, and use the remote controller to switch on and off all the five remote control switches to ensure normal operation.

[0012] (2) Connect the power supply to the AC 220V stabilized power source.

[0013] (3) Check that the RTO fuse and the knife switch are in the closed position.

[0014] (4) Close the 95A single-phase air switch.

[0015] (5) Close the 63A air switch to be tested.

[0016] (6) Leakage test: remote control twice.

[0017] (6) Overcurrent test: remote control twice.

[0018] (7) Short-circuit test: remote control once.

[0019] (8) Remove the AC 220V power line, remove the 63A test air switch, remove the ground wire, and the test is over.

[0020] Compared with the prior art, the present application has the following advantages:

[0021] 1. Leakage, overcurrent and short circuit test are all controlled by remote control to avoid the risk of electric shock caused by manual approach.

[0022] 2. The short circuit test tool uses an electromagnet to provide power to drive a V-shaped carbon rod connected to the live line to impact a V-shaped tungsten steel groove connected to the zero line, realizing spark and zero line short circuit, V-shaped large area contact, avoiding the ablation of carbon rods and tungsten steel by electric arc, and the high and low arrangement of the melting points of the two (the normal use temperature of carbon rods can reach 1450℃, the melting point of tungsten steel is 2850℃, and tungsten steel has high hardness, wear resistance, strength and toughness, heat resistance, corrosion resistance and a series of excellent properties, especially its high hardness), the temperature of electric spark is 3300 degrees, which is higher than the melting points of the two, but it is only instantaneous during short circuit, which can cause local temperature rise. The carbon rod is more prone to wear and tear, and the carbon rod is cheap and can be easily replaced after 1000 tests.

[0023] 3. In order to avoid the tripping of the test power supply caused by short circuit test, a first and second level protection is added under the condition that the 63A test air switch is refused to move, which are 95A air switch and 100A RTO fuse respectively. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 is a structural schematic diagram of the present application;

[0025] Fig. 2 is a sectional view of the present application;

[0026] Fig. 3 is a circuit principle diagram of the present application;

[0027] Wherein: 1, shell; 2, electromagnet; 3, telescopic rod; 4, carbon rod; 5, V-shaped groove; 6, spring. DETAILED DESCRIPTION

[0028] Example 1

[0029] As Figs. 1-3 shown, the present application is further described below in combination with the drawings: the portable low-voltage air switch comprehensive tester described in the present application is characterized in that it comprises a shell 1, an epoxy resin panel is arranged in the shell 1, a leakage test circuit and an overcurrent test circuit are arranged on the panel; a short circuit test device is arranged in the shell 1, and the leakage test circuit, the overcurrent test circuit and the short circuit test device are respectively connected to the measured air switch and the 220V stabilized power supply line through the live line and the zero line.

[0030] The leakage test circuit includes a 6.3kΩ resistor and a remote control closing switch connected in series between the live wire and the ground wire, a 22kΩ resistor and a remote control closing switch connected in series and then connected in parallel between the 6.3kΩ resistor and the remote control closing switch; a power-on timer A is arranged between the remote control closing switch and the zero wire.

[0031] The overcurrent test circuit includes a 3.09Ω resistor connected in series between the live wire and the zero wire, and a 95A AC contactor I connected in series with the 3.09Ω resistor; a 2.408Ω resistor connected in series between the live wire and the zero wire, and a 95A AC contactor II connected in series with the 2.408Ω resistor; the 2.408Ω resistor and the AC contactor II are connected in parallel with the 3.09Ω resistor and the AC contactor I, and a remote control switch is used to turn on and off the 220V AC power of the line circuit of the AC contactor I and the AC contactor II, and a power-on timer B is connected between the live wire and the zero wire.

[0032] The short circuit test device includes a 12V electromagnet 2, which is placed outside the shell 1, and the electromagnet 2 is connected with a telescopic rod 3, the end of the telescopic rod 3 is inside the shell 1, and a carbon rod 4 with a diameter of 10mm is installed in the epoxy tube, the end of the carbon rod 4 is V-shaped, a V-shaped groove 5 matching the end of the carbon rod 4 is arranged in the shell 1, the back of the V-shaped groove 5 is connected with one end of a spring 6, and the other end of the spring 6 is connected with the shell 1.

[0033] When the electromagnet 2 is not powered, the distance between the carbon rod 4 and the V-shaped groove 5 is 8mm, and when powered, the carbon rod 4 extends forward by 12mm; the carbon rod 4 is connected with the live wire by using a 2.5mm 2 soft copper wire; the V-shaped groove is connected with the zero wire by using a 2.5mm 2 soft copper wire.

[0034] A first protection and a second protection are further arranged between the 220V stabilized power supply and the portable low-voltage air switch comprehensive tester, and the first protection and the second protection are respectively a 95A air switch and a 100A RTO fuse.

[0035] The use method of the portable low-voltage air switch comprehensive tester includes the following steps:

[0036] (1) Ground the instrument, install the connection of the 63A air switch to be tested, and use the remote control to turn on and off all the five remote control switches once to ensure normal operation;

[0037] (2) Connect the power supply to the AC 220V stabilized power source;

[0038] (3) Check that the RTO fuse and the knife switch are in the closed position;

[0039] (4) Close the 95A single-phase air switch;

[0040] (5) Close the 63A air switch to be tested;

[0041] (6) Leakage test: remote control in 2 times;

[0042] (6) Overcurrent test: remote control in 2 times;

[0043] (7) Short circuit test: remote control 1 time;

[0044] (8) Remove AC 220V power line, remove 63A test air switch, remove the ground wire, and the test is over.

[0045] The portable low-voltage air switch comprehensive tester of the application is developed for the current mainstream 63A meter air switch, and one instrument can realize leakage, overcurrent and short circuit tests. The whole instrument is packaged in an external aluminum alloy shell, and all switches, resistors and other components are installed on the epoxy resin panel, and the wiring is inside the box.

[0046] (1) Leakage test: in order to test the leakage current exceeding 30mA, 0.1s must be reliably tripped; in the case of a 6.3kΩ resistor in series between the firewire and the ground, the voltage is 220V (provided by a stable voltage source), DC12V power remote control AC220V switch closing, the ground current (leakage current) is 35mA, and the 63A air switch should be reliably tripped within 0.1s, and the action time is recorded by the power-on timer A; in order to test the leakage current less than 15mA, it must be reliably not tripped, and a 22kΩ resistor is connected in series between the firewire and the ground, and the voltage is 220V (provided by a stable voltage source), DC12V power remote control AC220V switch closing, the ground current (leakage current) is 10mA, and the 63A air switch should be reliably not tripped, and if it malfunctions, the action time is recorded by the power-on timer A.

[0047] (2) Overcurrent test: in order to test 1.13 times rated current within one hour without action test (overcurrent), the application connects a 3.090Ω resistor in series between the firewire and the zero line, and connects a 95A AC contactor, and the AC220V switch is controlled by the DC12V power to turn on and off the 220V AC of the line circuit of the AC contactor. This test needs to last for 3600 seconds or more (recorded by the power-on timer B), and the switch should not trip within 3600 seconds if it is of good quality; in order to test 1.45 times rated current within one hour must be action test (overcurrent), the application connects a 2.408Ω resistor in series between the firewire and the zero line, and connects a 95A AC contactor, and the AC220V switch is controlled by the DC12V power to turn on and off the 220V AC of the line circuit of the AC contactor. This test needs to last for 3600 seconds, and the switch should trip within 3600 seconds if it is of good quality;

[0048] (3) Short-circuit test: This test is conducted in an epoxy resin box. The 12V electromagnet 2 is placed outside the box, and the end of the telescopic rod 3 is inside the box. A 10mm diameter carbon rod 4 is installed at the end, which is enclosed in an epoxy tube. The end is V-shaped. When the electromagnet 2 is not energized, the distance between the carbon rod 4 and the V-shaped groove 5 is 8mm. When energized, it extends forward 12mm. To cushion the impact force, two springs 6 are added to the rear of the V-shaped groove 5. The carbon rod 4 uses a 2.5mm² soft copper wire to connect to the live wire; the tungsten steel V-shaped groove 5 uses a 2.5mm² soft copper wire to connect to the neutral wire. The upper cover of the box can be opened to facilitate the replacement of the carbon rod 4 and the wiping of carbon powder burned by the short-circuit arc.

Claims

1. A portable low-voltage circuit breaker comprehensive tester, characterized in that: The invention comprises a housing (1), wherein an epoxy resin panel is provided in the housing (1), and a leakage test circuit and an overcurrent test circuit are provided on the panel; a short-circuit test device is provided in the housing (1), and the leakage test circuit, the overcurrent test circuit, and the short-circuit test device are connected to a 63A circuit breaker to be tested and an AC220V power line of an AC220V voltage stabilizer through a live wire and a neutral wire respectively; The leakage test circuit includes connecting a 6.3kΩ resistor and a remote control closing switch I in series between the live wire and the ground wire, a 22kΩ resistor and a remote control closing switch II in series, and then connected in parallel with the 6.3kΩ resistor and the remote control closing switch I; the remote control closing switch I, the remote control closing switch II and the neutral wire are all connected to the power-on timer A; The overcurrent test circuit includes a 3.09Ω resistor connected in series between the live wire and the neutral wire, and the 3.09Ω resistor is connected in series with a 95A AC contactor I; a 2.408Ω resistor is also connected in series between the live wire and the neutral wire, and the 2.408Ω resistor is connected in series with a 95A AC contactor II; the 2.408Ω resistor and the AC contactor II are connected in parallel with the 3.09Ω resistor and the AC contactor I, the contactor remote control switch is for the line circuit of the AC contactor I and the AC contactor II to turn on and off 220V AC power, and the power-on timer B is connected between the live wire and the neutral wire; The short-circuit test device comprises a 12V electromagnet (2), the electromagnet (2) is placed outside the housing (1), the electromagnet (2) is connected to a telescopic rod (3), the electromagnet (2) is connected to an electromagnet remote control switch, the end of the telescopic rod (3) is inside the housing (1), a carbon rod (4) with a diameter of 10 mm is installed on the end and is sleeved in an epoxy tube, the end of the carbon rod (4) is V-shaped, a V-shaped groove (5) matching the end of the carbon rod (4) is provided in the housing (1), the back of the V-shaped groove (5) is connected to one end of a spring (6), and the other end of the spring (6) is connected to the housing (1).

2. A portable low-voltage circuit breaker comprehensive tester according to claim 1, characterized in that: When the electromagnet (2) is not energized, the distance between the carbon rod (4) and the V-shaped groove (5) is 8 mm. When energized, the carbon rod (4) extends forward 12 mm. The carbon rod (4) uses a 2.5 mm 2 Soft copper wire connects to the live wire; V-groove uses 2.5mm 2 Soft copper wire is connected to the neutral wire.

3. A portable low-voltage circuit breaker comprehensive tester according to claim 1, characterized in that: The first-level protection and the second-level protection are respectively added between the 220V voltage stabilizer and the portable low-voltage circuit breaker comprehensive tester. The first-level protection is a 95A single-phase circuit breaker, and the second-level protection is a 100A RTO fuse on the live line and a 100A knife switch on the neutral line.

4. The method for using a portable low-voltage circuit breaker comprehensive tester according to claim 3 is characterized in that: The following steps are involved: (1) Ground the instrument, install and connect the 63A circuit breaker to be tested, and use the remote control to open and close the remote control closing switch I, remote control closing switch II, contactor remote control switch, and electromagnet remote control switch to ensure that they are normal; (2) Connect the AC220V power cord to the power supply; (3) Check that the RTO fuse and the knife switch are in the closed position; (4) Close the 95A single-phase circuit breaker; (5) Close the 63A circuit breaker under test; (6) Leakage test: remote control twice; (6) Overcurrent test: remote control twice; (7) Short circuit test: remote control 1 time; (8) Remove the AC220V power cord, remove the 63A circuit breaker under test, remove the ground wire, and the test is complete.

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