CN110988447A

CN110988447A - Circuit diagram of surge current impact tester

Info

Publication number: CN110988447A
Application number: CN202010007389.8A
Authority: CN
Inventors: 陈健武
Original assignee: Guangdong Xincheng Technology Industry Co Ltd
Current assignee: Guangdong Xincheng Technology Industry Co Ltd
Priority date: 2020-01-04
Filing date: 2020-01-04
Publication date: 2020-04-10

Abstract

The invention discloses a surge current impact tester circuit diagram, which comprises a case and a handle, wherein the case is movably connected with the handle, the front side of the case is provided with a screen, a key and a test terminal, the back side of the case is provided with a power socket and a cooling fan, and the inside of the case is provided with a detection circuit for detecting surge current. The instrument is mainly used for surge current impact test of resistive elements, particularly NTC thermistors, and is particularly suitable for the following application occasions: 1. and (3) testing the resistance of the resistive element to surge current impact, namely, testing the service life of the resistive element. 2. The suppression capability of the resistive element on surge current surge is evaluated through the peak current. 3. For the design of the power supply type circuit, the selection of the element for restraining the surge current, particularly the NTC thermistor, can be facilitated.

Description

Circuit diagram of surge current impact tester

Technical Field

The invention relates to the technical field of electricity, in particular to a circuit diagram of an inrush current impact tester.

Background

The surge current refers to the peak current flowing into the power supply equipment at the moment the power supply is turned on. This peak current is much greater than the steady state input current due to the rapid charging of the input filter capacitor. The power supply should limit the surge levels that the AC switch, rectifier bridge, fuse, EMI filter devices can withstand. The loop is repeatedly switched and the AC input voltage should not damage the power supply or cause the fuse to blow.

Therefore, the surge current detection is very important, and most of the existing surge current detection equipment is large in size, complex to operate and inconvenient to use.

Disclosure of Invention

The present invention is directed to a circuit diagram of an inrush current surge tester, so as to solve the problems in the background art.

In order to achieve the purpose, the invention provides the following technical scheme:

the utility model provides a surge current impact tester circuit diagram, includes quick-witted case and handle, quick-witted case and handle swing joint, the front of machine case is equipped with screen, button and test terminal, and the back of machine case is equipped with supply socket and radiator fan, and the inside of machine case is equipped with the detection circuitry who is used for detecting surge current.

As a further scheme of the invention: the number of the keys is multiple.

As a further scheme of the invention: the detection circuit comprises a rectifier bridge T, a resistive element Rx to be detected, a capacitor Cx and a load Ro, wherein input ends 1 and 3 of the rectifier bridge T are respectively connected with two ends of an alternating current power supply to be detected, an anode output end 2 of the rectifier bridge T is connected with the resistive element Rx to be detected, the other end of the resistive element Rx to be detected is connected with the capacitor Cx and the load Ro, and the other end of the load Ro is connected with the capacitor Cx and a cathode output end 4 of the rectifier bridge T.

As a further scheme of the invention: the resistive element to be tested is an NTC thermistor.

As a further scheme of the invention: the capacitance Cx is a filter capacitance.

As a further scheme of the invention: the screen adopts a 5-inch liquid crystal screen.

As a further scheme of the invention: the test terminals include a test terminal RX and a test terminal CX.

Compared with the prior art, the invention has the beneficial effects that: the invention can rapidly obtain the surge peak current and the surge current waveform. The instrument is mainly used for surge current impact test of resistive elements, particularly NTC thermistors, and is particularly suitable for the following application occasions: 1. and (3) testing the resistance of the resistive element to surge current impact, namely, testing the service life of the resistive element. 2. The suppression capability of the resistive element on surge current surge is evaluated through the peak current. 3. For the design of the power supply type circuit, the selection of the element for restraining the surge current, particularly the NTC thermistor, can be facilitated.

Drawings

Fig. 1 is a front structural view of the present invention.

Fig. 2 is a rear view of the present invention.

Fig. 3 is a circuit diagram illustrating the testing principle of the present invention.

In the figure: 1-screen, 2-key, 3-chassis, 4-test terminal, 5-handle, 6-power socket, 7-radiator fan.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1: referring to fig. 1-3, in an embodiment of the present invention, a circuit diagram of an inrush current surge tester includes a case 3 and a handle 5, where the case 3 is movably connected to the handle 5, a screen 1, a key 2, and a test terminal 4 are disposed on a front surface of the case 3, a power socket 6 and a heat dissipation fan 7 are disposed on a back surface of the case 3, and a detection circuit for detecting an inrush current is disposed inside the case. The key 2 is plural.

The detection circuit comprises a rectifier bridge T, a resistive element Rx to be detected, a capacitor Cx and a load Ro, wherein input ends 1 and 3 of the rectifier bridge T are respectively connected with two ends of an alternating current power supply to be detected, an anode output end 2 of the rectifier bridge T is connected with the resistive element Rx to be detected, the other end of the resistive element Rx to be detected is connected with the capacitor Cx and the load Ro, and the resistive element to be detected of the load Ro is an NTC thermistor. The capacitance Cx is a filter capacitance. Test terminal 4 includes test terminal RX and test terminal CX, and during the wiring, test terminal RX connects the resistance that awaits measuring, and filter capacitance is connected to test terminal CX, if filter capacitance adopts electrolytic capacitor, pays attention to the differentiation of positive negative pole. The terminal 1 pin is a positive electrode, and the other pin is a negative electrode.

The interface of the ICT-2015A type surge current impact tester is mainly divided into the following parts:

1. title bar: the model and the name of the instrument are displayed;

2. a pattern area: the method is used for displaying the waveform of the surge current in real time. The lower right corner of the graph area displays current curve resolution information and an instrument working state;

current curve resolution: the longitudinal direction of the graph, the magnitude of the current represented by each grid. Shown on the instrument as "RES: xx A";

the instrument automatically selects a proper resolution according to an actual measurement result, wherein the minimum resolution is 1A/lattice, and the maximum resolution is 20A/lattice;

the working state is as follows: in the test process, the instrument displays 'test' and displays 'standby' when the instrument is not in the test state;

3. data area: the device is used for displaying the test result in real time, wherein the test result comprises peak current and test times;

4. parameter area: the test parameters for setting the instrument comprise 4 parameters of load, impact time, impact interval time and impact times.

Example 2: on the basis of the embodiment 1, the screen 1 adopts a 167-thousand-color 5-inch liquid crystal screen, the input voltage is AC220V ± 20%, the size of a chassis is 278mm × 93mm × 315mm, the load current is 0.1-15.0A, the resolution is 0.1A, and the precision is < = 3%.

The circuit is characterized in that the circuit can not only accurately detect two stable states of the closing and the opening of the wind pressure switch, but also carry out corresponding detection and judgment when the wind pressure switch is in a shaking state. When the wind pressure switch S1 is in an off state, the voltage of the non-inverting terminal of the 3 rd pin of the comparator IC circuit U1A is zero, and at this time, the voltage of the inverting terminal of the 2 nd pin of the comparator IC circuit U1A is the voltage drop of the conducting tube of the diode D1, which is about 0.35 to 0.7V, so that the output port of the 1 st pin of the comparator IC circuit U1A is constantly at a low level, and thus the voltage of the TEST _ IO terminal is also constantly at a low level; when the wind pressure switch S1 is in a closed state, the voltage of the 3 rd pin in the phase of the comparator IC circuit U1A is greater than the voltage drop of the forward conducting tube of the diode D1 under the partial pressure of the resistors R1 and R2, so the output port of the 1 st pin of the comparator IC circuit U1A is constantly at a high level, and thus the voltage of the TEST _ IO terminal is also constantly at a high level; when the wind pressure switch S1 is in "shaking" state, the output port voltage of the 1 st pin of the corresponding comparator IC circuit U1A is in pulse state, and under the charging and discharging and filtering action of the capacitors C1 and C2, the TEST _ IO terminal voltage is in a certain intermediate voltage state between high level and low level. When the signal output end TEST _ IO level is detected to be a constant low level, the wind pressure switch S1 can be judged to be in a disconnected state; when the signal output end TEST _ IO level is detected to be a constant high level, the wind pressure switch S1 can be judged to be in a closed state; when the voltage of the signal output terminal TEST _ IO is detected to be between the high level and the low level, it can be determined that the wind pressure switch S1 is in the third state "jitter" state.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The utility model provides an inrush current impact tester circuit diagram, includes quick-witted case (3) and handle (5), its characterized in that, quick-witted case (3) and handle (5) swing joint, the front of quick-witted case (3) is equipped with screen (1), button (2) and test terminal (4), and the back of quick-witted case (3) is equipped with supply socket (6) and radiator fan (7), and the inside of quick-witted case is equipped with the detection circuitry who is used for detecting inrush current.

2. An inrush current surge tester circuit diagram according to claim 1, wherein there are a plurality of keys (2).

3. The circuit diagram of claim 1, wherein the detection circuit comprises a rectifier bridge T, a resistive element to be tested Rx, a capacitor Cx, and a load Ro, wherein input terminals 1 and 3 of the rectifier bridge T are respectively connected to two ends of the ac power to be tested, a positive output terminal 2 of the rectifier bridge T is connected to the resistive element to be tested Rx, the other end of the resistive element to be tested Rx is connected to the capacitor Cx and the load Ro, and the other end of the load Ro is connected to the capacitor Cx and a negative output terminal 4 of the rectifier bridge T.

4. The inrush current surge tester circuit of claim 3, wherein the resistive element to be tested is an NTC thermistor.

5. The inrush current surge tester circuit of claim 3, wherein the capacitor Cx is a filter capacitor.

6. The circuit diagram of an inrush current surge tester of claim 1, wherein the screen (1) is a 5-inch liquid crystal screen.

7. An inrush current surge tester circuit according to claim 1, wherein the test terminals (4) comprise a test terminal RX and a test terminal CX.