Reliable detection device for relay working status

Abstract

The utility model discloses a reliable detection device for the working state of a relay, comprising: a resistance detection device and a host computer, wherein the resistance detection device is provided with a test end, the test end is electrically connected to the contact of the relay and forms a detection loop, the resistance detection device can calculate the contact resistance of the relay according to the detection current input to the relay and the voltage drop generated after the detection current passes through the relay; the host computer is communicatively connected to the resistance detection device, and is used to obtain the contact resistance measured by the resistance detection device, and compare it with the set resistance threshold value to determine whether the relay is in the on or off state, and the host computer can also display the contact resistance for the detection personnel to read. The utility model can not only accurately determine the on and off state of the relay in real time, but also can intuitively reflect the slight changes in the contact resistance of the relay when it is in operation, can provide higher measurement accuracy and stability, and greatly improve the reliability of the detection result.

Description

Technical Field

[0001] The utility model relates to the technical field of relays, in particular to a reliable detection device for the working state of a relay. Background Art

[0002] With the rapid development of the new energy electric vehicle industry, higher and higher requirements are put forward for relays. Relays in electric vehicles are mainly used to control the connection and disconnection of circuits. Since the high-voltage system of new energy electric vehicles needs to be switched frequently, relays need to have high reliability and be able to work stably for a long time in harsh working environments. At the same time, in order to reduce the energy consumption of new energy electric vehicles, relays also need to have lower resistance to reduce energy loss in the circuit. Therefore, relays need to be tested before leaving the factory to ensure the quality of the relays and meet the use requirements.

[0003] When the relay is not working, its main contact and auxiliary normally open contact are in the disconnected state, and the auxiliary normally closed contact is in the on state; conversely, when the relay is in the energized state, its main contact and auxiliary normally open contact are in the on state, and the auxiliary normally closed contact is in the off state. At present, the way to detect the contact state of the relay is generally to determine whether the contact is in the on or off state by detecting the internal resistance of the circuit. The detection result can only be on or off, and it cannot reflect the slight change of the contact resistance when the relay is working. It is easy to cause misjudgment due to poor contact or excessive contact resistance. Therefore, it is necessary to improve the existing technology to overcome the defects in the existing technology. Utility Model Content

[0004] The problem to be solved by the utility model is to provide a reliable detection device for the working state of a relay, so as to overcome the defect that the prior art cannot reflect the slight change of the contact resistance of the contact point when the relay is in operation, and is prone to misjudgment due to poor contact or excessively high contact resistance.

[0005] The utility model adopts the following technical scheme to solve the technical problems: a reliable detection device for the working state of a relay, which is used to detect whether the relay is in a normal on or off state, wherein the relay is provided with at least one pair of contacts; the reliable detection device for the working state of the relay comprises: a resistance detection device and a host computer, wherein the resistance detection device is provided with a test end, the test end is electrically connected to the contact of the relay and forms a detection loop, the resistance detection device is used to input a detection current and a detection voltage to the relay through the test end, and the resistance detection device can calculate the contact resistance of the relay according to the detection current input to the relay and the voltage drop generated after the detection current passes through the relay; the host computer is communicatively connected to the resistance detection device, which is used to obtain the contact resistance measured by the resistance detection device, and compare it with a set resistance threshold value to determine whether the relay is in an on or off state, and the host computer can also display the contact resistance for the detection personnel to read.

[0006] As a further improvement of the present utility model, the resistance detection device adopts a DC low resistance tester.

[0007] As a further improvement of the present invention, the reliable detection device for the working state of the relay also includes a voltage regulation module and an adjustable load module, and the voltage regulation module and the adjustable load module are both electrically connected to the DC low resistance tester. The voltage regulation module is used to adjust the detection voltage value output by the test end of the DC low resistance tester, and the adjustable load module is used to adjust the detection current value output by the test end of the DC low resistance tester.

[0008] As a further improvement of the utility model, the voltage regulation module and the adjustable load module are both built into the DC low resistance tester.

[0009] As a further improvement of the present invention, the reliable detection device for the relay working state also includes a touch screen, which is electrically connected to the voltage regulation module and the adjustable load module, and the touch screen is used to adjust and display the detection voltage value and the detection current value.

[0010] As a further improvement of the present invention, the test end is electrically connected to the contact of the relay by a four-terminal wiring method.

[0011] As a further improvement of the utility model, the relay is provided with a pair of contacts, which are a pair of main contacts;

[0012] Or the relay is provided with two pairs of contacts, one pair of contacts being a pair of main contacts, and the other pair of contacts being a pair of auxiliary contacts;

[0013] Alternatively, the relay is provided with a pair of contacts and three auxiliary contacts, wherein the pair of contacts is a pair of main contacts, and the three auxiliary contacts are respectively a normally open contact, a normally closed contact and a common contact.

[0014] The beneficial effects of the utility model are as follows: the utility model provides a reliable detection device for the working state of a relay, which adopts a resistance detection device to cooperate with a host computer to detect the relay, and by comparing the detected contact resistance with the set resistance threshold, not only can the on-off state of the relay be judged in real time and accurately, but also the slight changes in the contact resistance when the relay is in operation can be intuitively reflected, and higher measurement accuracy and stability can be provided, thereby avoiding misjudgment caused by poor contact or excessively high contact resistance, ensuring the accuracy of the detection result, and greatly improving the reliability of the detection result. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic block diagram of a reliable detection device for relay working status of the utility model;

[0016] Figure 2 This is a schematic diagram of the structure of the relay to be detected in the utility model. DETAILED DESCRIPTION

[0017] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0018] See also Figure 1 and Figure 2 The utility model provides a reliable detection device for the working state of a relay, which is used to detect whether the relay is in a normal on or off state. The relay to be detected is provided with at least one pair of contacts.

[0019] The utility model discloses a reliable detection device for the working state of a relay, comprising: a resistance detection device and a host computer, wherein the resistance detection device is provided with a test terminal, and the test terminal is electrically connected to the contact of the relay to form a detection circuit. Among them, a test clip can be connected to the test terminal to facilitate clamping on the contact of the relay. The resistance detection device is used to input a detection current and a detection voltage to the relay through the test terminal, and the resistance detection device can calculate the contact resistance of the relay contact according to Ohm's law by inputting the detection current of the relay and the voltage drop generated after the detection current passes through the relay.

[0020] Furthermore, the host computer is communicatively connected to the resistance detection device to obtain the contact resistance value of the contact point measured by the resistance detection device.

[0021] The state detection of the relay is realized by connecting the contacts with a resistance detection device. When the relay works to make the contacts conductive, the host computer can obtain the contact resistance measured by the resistance detection device in real time; similarly, when the relay does not work to make the contacts disconnected, the host computer can also obtain the contact resistance measured by the resistance detection device in real time. According to these acquired contact resistance values, the host computer will calculate according to the pre-set program. The host computer sets a resistance threshold and compares the contact resistance value with the set resistance threshold to determine the on-off state of the contact. If the contact resistance value is lower than the set resistance threshold, the host computer will determine that the contact is in the conductive state; conversely, if the contact resistance value is higher than the set resistance threshold, the host computer will determine that the contact is in the disconnected state. At the same time, the host computer can also display the contact resistance value for the detection personnel to read.

[0022] Therefore, the utility model adopts a resistance detection device to cooperate with the host computer to detect the relay. By comparing the detected contact resistance with the set resistance threshold, it can not only accurately judge the on and off state of the relay in real time, but also can intuitively reflect the slight changes in the contact resistance when the relay is working. It can provide higher measurement accuracy and stability, avoid misjudgment due to poor contact or excessive contact resistance, ensure the accuracy of the detection results, and greatly improve the reliability of the detection results.

[0023] Preferably, the resistance detection device of the utility model adopts a DC low resistance tester, which can provide high measurement accuracy and stability for the contact resistance of the milliohm level. Among them, the test end of the DC low resistance tester is electrically connected to the contact of the relay using a four-terminal wiring method, which can effectively eliminate the influence of the wiring resistance on the contact resistance detection and ensure the reliability of the detection.

[0024] Some relays often have specific requirements for the test load during testing. For example, the GJB360B electronic and electrical component test method stipulates the load: the test current is (100±10)mA, and the test voltage is 3V~28V (DC). Since the contact resistance of the relay is in the milliohm level, for example, when the contact resistance is 0.1mΩ, the calculated contact voltage drop is 10 -6 V, it is difficult to meet this accuracy requirement using some conventional digital multimeters. If a high-precision acquisition card is used, the cost is too high and it is not easy to implement. However, the utility model uses a DC low resistance tester to perform high-precision detection of the contact resistance of the relay. To meet this demand, after investigation, it was found that the test current of the existing DC low resistance testers on the market can generally meet the requirement of 100mA detection current, but the detection voltage does not meet the requirement, and the detection voltage is not adjustable.

[0025] In this regard, the reliable detection device for the working state of a relay of the utility model also includes a voltage regulation module and an adjustable load module. The voltage regulation module and the adjustable load module are both electrically connected to a DC low resistance tester. The voltage regulation module is used to adjust the detection voltage value output by the test end of the DC low resistance tester so that the detection voltage value meets the relay detection requirements. At the same time, the detection current value output by the test end of the DC low resistance tester is adjusted through the adjustable load module so that the detection current value can also meet the requirements, thereby realizing the test under the specific requirements.

[0026] Among them, the voltage regulation module and the adjustable load module are both built into the DC low resistance tester.

[0027] In addition, the reliable detection device for the working state of the relay of the utility model also includes a touch screen, which is electrically connected to the voltage regulation module and the adjustable load module. The detection voltage value and the detection current value can be conveniently adjusted and displayed through the touch screen.

[0028] At present, relays on the market can be roughly divided into two types: with auxiliary contacts and without auxiliary contacts. Relays without auxiliary contacts are equipped with a pair of contacts, which are a pair of main contacts. Relays with auxiliary contacts are usually divided into two auxiliary contacts and three auxiliary contacts. For relays with two auxiliary contacts, there are two pairs of contacts in total, one pair of contacts is a pair of main contacts, and the other pair of contacts is a pair of auxiliary contacts; for relays with three auxiliary contacts, there are a pair of main contacts, a normally open contact, a normally closed contact and a common contact.

[0029] This embodiment takes a relay with three auxiliary contacts as an example to specifically illustrate the test steps.

[0030] like Figure 1 and Figure 2As shown, first, a pair of main contacts of the relay is tested, and the pair of main contacts are main contact A and main contact B. According to the specifications of the relay, select the appropriate resistance test gear on the DC low resistance tester, and adjust the voltage adjustment module to adjust the detection voltage to the voltage range required by the relay, and then adjust the adjustable load module to adjust the detection current to the current range required by the relay. Then connect the main contact A and the main contact B to the DC low resistance tester. When the relay is not working, the main contact A and the main contact B are disconnected, and the contact resistance detected by the DC low resistance tester is infinite. The host computer judges that the relay is in the disconnected state; when the relay is working and energized, the main contact A and the main contact B are connected, and the contact resistance detected by the DC low resistance tester is XmΩ. If the contact resistance is lower than the set resistance threshold, the host computer will judge that the relay is in the on state; conversely, if the contact resistance is higher than the set resistance threshold, the host computer will judge that the contact is in the disconnected state. At this time, the operator can manually analyze and judge based on the contact resistance displayed by the host computer.

[0031] Secondly, the three auxiliary contacts are tested, which are the normally open contact NO, the normally closed contact NC and the common contact COM. Similarly, according to the detection requirements of the auxiliary contacts, first select the appropriate resistance test gear on the DC low resistance tester, and adjust the voltage regulation module and the adjustable load module so that the detection voltage and detection current output by the test end of the DC low resistance tester are within the required range. After that, the normally open contact NO and the common contact COM are connected to a DC low resistance tester, and the normally closed contact NC and the common contact COM are connected to another DC low resistance tester. Similar to the main contact detection, the corresponding contact contact resistance is detected when the relay is not working and when it is working, so as to determine the on-off state of the auxiliary contacts.

[0032] The host computer in the present invention may be, but is not limited to, an industrial computer, a personal computer, an industrial PC, a human-machine interface (HMI), etc.

[0033] Optionally, the DC low resistance tester in this embodiment adopts a precision resistance tester model RK2518-32 produced by Shenzhen Meiruike Electronic Technology Co., Ltd., the voltage regulation module adopts a programmable low-voltage DC source (output voltage 0~60V, output current 0~30A) currently available on the market, and the adjustable load module adopts a DC adjustable load (adjustment range 1KΩ~60KΩ) currently available on the market.

[0034] To sum up, the reliable detection device for the working state of a relay of the utility model adopts a resistance detection device to cooperate with a host computer to detect the relay. By comparing the detected contact resistance with the set resistance threshold, it can not only accurately judge the on-off state of the relay in real time, but also can intuitively reflect the slight changes in the contact resistance when the relay is working. It can provide higher measurement accuracy and stability, avoid misjudgment due to poor contact or excessive contact resistance, ensure the accuracy of the detection result, and can greatly improve the reliability of the detection result.

[0035] In the above description, many specific details are described to facilitate a full understanding of the present invention. However, the above description is only a preferred embodiment of the present invention. The present invention can be implemented in many other ways different from those described herein, so the present invention is not limited by the specific implementation disclosed above. At the same time, any person familiar with the technical field can make many possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.

Claims

1. A reliable detection device for the working state of a relay, used to detect whether the relay is in a normal on or off state, wherein the relay is provided with at least one pair of contacts; characterized in that: The invention comprises: a resistance detection device and a host computer, wherein the resistance detection device is provided with a test end, the test end is electrically connected to the contact of the relay and forms a detection loop, the resistance detection device is used to input a detection current and a detection voltage to the relay through the test end, and the resistance detection device can calculate the contact resistance of the relay contact according to the detection current input to the relay and the voltage drop generated after the detection current passes through the relay; The host computer is communicatively connected to the resistance detection device, and is used to obtain the contact resistance value measured by the resistance detection device, and compare it with the set resistance threshold to determine whether the relay is in the on or off state. At the same time, the host computer can also display the contact resistance value for the detection personnel to read.

2. The device for reliable detection of relay working state according to claim 1, characterized in that: The resistance detection device adopts a DC low resistance tester.

3. The reliable detection device for relay working state according to claim 2 is characterized in that: It also includes a voltage regulation module and an adjustable load module, both of which are electrically connected to the DC low resistance tester. The voltage regulation module is used to adjust the detection voltage value output by the test end of the DC low resistance tester, and the adjustable load module is used to adjust the detection current value output by the test end of the DC low resistance tester.

4. The device for reliable detection of relay working state according to claim 3, characterized in that: The voltage regulating module and the adjustable load module are both built in the DC low resistance tester.

5. The device for reliable detection of relay working state according to claim 3, characterized in that: It also includes a touch screen, which is electrically connected to the voltage regulating module and the adjustable load module, and is used to adjust and display the detection voltage value and the detection current value.

6. The device for reliable detection of relay working state according to claim 1, characterized in that: The test end is electrically connected to the contact of the relay by using a four-terminal wiring method.

7. The device for reliable detection of relay working state according to claim 1, characterized in that: The relay is provided with a pair of contacts, which are a pair of main contacts; Or the relay is provided with two pairs of contacts, one pair of contacts being a pair of main contacts, and the other pair of contacts being a pair of auxiliary contacts; Alternatively, the relay is provided with a pair of contacts and three auxiliary contacts, wherein the pair of contacts is a pair of main contacts, and the three auxiliary contacts are respectively a normally open contact, a normally closed contact and a common contact.

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