CN105158575A - Automatic low resistance test device - Google Patents
Automatic low resistance test device Download PDFInfo
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- CN105158575A CN105158575A CN201510509669.8A CN201510509669A CN105158575A CN 105158575 A CN105158575 A CN 105158575A CN 201510509669 A CN201510509669 A CN 201510509669A CN 105158575 A CN105158575 A CN 105158575A
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Abstract
The invention relates to an automatic low resistance test device and belongs to the resistance testing technical field. The automatic low resistance test device is especially suitable for initiating explosive device resistance tests. The automatic low resistance test device includes a main control unit 1, a constant current source module 2, a test channel switching circuit 3, a signal conditioning circuit 4, an analog-to-digital conversion circuit 5 and the like; the main control unit 1 successively outputs chip selection codes of a positive test channel and a negative test channel according to corresponding test items so as to control the test channel switching circuit 3 to perform switching, so that the output current of the constant current source module 2 can pass through a gated initiating explosive device loop; the signal conditioning circuit 4 performs filtering and differential amplification on port voltage of the gated loop; the analog-to-digital conversion circuit 5 acquires related voltage signals and transmits the voltage signals to the main control unit 1 for calculation, so that the resistance values of a tested item under test current of different directions can be obtained, and the test result of the tested item can be obtained through averaging; and the main control unit 1 repeats the above steps according to a preset test sequence so that test on the other test items can be completed; and therefore, automatic, rapid and comprehensive test on the resistance of an initiating explosive device can be realized.
Description
Technical field
The invention belongs to the technical field of resistance test, relate to a kind of low resistance proving installation automatically, be specially adapted to priming system resistance test.
Background technology
In prior art, generally all can select commercially available resistance meter or multimeter when relating to resistance measurement.But when measuring priming system resistance, for the consideration of secure context, its measuring current strictly must be limited in a very little numerical range interior (below 5mA).When measuring current is very little, the voltage that measured resistance two ends produce is also very small, the directional jamming electromotive forces such as the thermoelectrical potential so such as produced between dissimilar metal, primary element electromotive force are as having a strong impact on test result, and obviously common testing apparatus can not solve the problem.Therefore some special proving installations have been there is, if publication number is disclose one " low resistance admeasuring apparatus " in the patent document of CN101706534A, it makes control core with microcontroller, the direction of measuring current and the gain of amplifier is changed by adopting two-way precision DC constant current source and two-way gain-programmed amplifier, obtain the magnitude of voltage of measured resistance under different directions measuring current, by calculating the average voltage that positive and negative measuring current produces, just directional jamming electromotive force can be got rid of.
Generally for strict guarantee priming system and control path is normal, during quality inspection, each priming system has a large amount of resistance test items, and said method has following deficiency:
(1) test mode is artificial point-to-point test, and testing efficiency is low, and human cost is higher;
(2) test item is the loop resistance being strobed priming system loop, needs to ensure that the lead-in wire of corresponding test item correctly contacts with the test pencil of tester during test, and when lead-in wire more than, manual measurement is surveyed and test leakage very easily by mistake;
(3) practice shows, the resistance of priming system partial test item is less than 0.5 Ω, and the resistance test result of the said equipment contains the line resistance of equipment itself, causes resistance test inaccurate.
A kind of multi-channel measurement method is also disclosed to improve testing efficiency in prior art, simultaneously its testing scheme utilizes multiple passage to carry out multinomial resistance measurement, by this scheme, in test process, priming system to be measured has multiple loop be strobed, easily cause potential safety hazard, and can not get correct test result.
Summary of the invention
The shortcoming of prior art in view of the above, the object of the present invention is to provide a kind of low resistance proving installation automatically, can test priming system resistance automatically comprehensively fast, easy to operate, automaticity is high.
A kind of low resistance proving installation automatically, comprises main control unit, constant current source module, test channel commutation circuit, signal conditioning circuit, analog to digital conversion circuit, push-button unit, display unit and storage unit.
Described constant current source module, comprise high precise current source and high precision inspection leakage resistance, its current output terminal is connected to anode test point, and one end that negative terminal test point examines leakage resistance with high precision is connected, and the other end of described high precision inspection leakage resistance connects the ground of constant current source.
Described test channel commutation circuit, comprise CPLD and switch module, every root lead-in wire of product to be measured is all connected respectively to anode test point and negative terminal test point by two switch modules, the action of switch module is controlled by CPLD, and described switch module is primarily of normally opened relay FR, triode Q1 and divider resistance R102, R103 composition.
Described signal conditioning circuit, comprises filtering circuit and differential amplifier circuit, for carrying out filtering and differential amplification to the voltage between anode test point and negative terminal test point.
Analog-digital conversion circuit as described for gathering high precision inspection leakage resistance both end voltage and by the voltage after differential amplification, and is transferred to digital data transmission and is calculated to main control unit.
Described main control unit, comprises single-chip microcomputer, for control testing process, export test channel sheet code selection to CPLD, calculate gating loop loop resistance, test result is fed back to man-machine interaction unit.
Based on the low resistance automatic test approach of said apparatus, it is realized by following steps:
Step one: system initialization, connects short-circuiting cable and carries out self-inspection, calculate and preserve each test channel line resistance;
Step 2: main control unit exports the sheet code selection of forward resistance test channel according to corresponding test item, correspondence lead-in wire is connected respectively to anode test point and negative terminal test point by test channel commutation circuit; High precise current source exports steady current under the control of main control unit, and electric current flows into the priming system loop of gating from anode test point, flows out and examine the ground of leakage resistance to constant current source through high precision from negative terminal test point;
Step 3: the voltage signal of positive and negative end test point delivers to analog to digital conversion circuit after signal conditioning circuit filtering, differential amplification;
Step 4: under the control of main control unit, analog to digital conversion circuit gathers the voltage signal U2 at the above-mentioned voltage signal U1 through differential amplification and high precision inspection leakage resistance two ends, and delivers to main control unit and carry out subsequent treatment;
Step 5: main control unit utilizes formula:
Calculating resistance value R1, obtain forward resistance value, in formula: A is the enlargement factor of differential amplifier circuit, is the resistance of high precision inspection leakage resistance;
Step 6: main control unit exports the sheet code selection of back resistance test channel according to described test item, correspondence lead-in wire is received anode test point and negative terminal test point by test channel commutation circuit, then repeats step 3, four, five and obtain back resistance value;
Step 7: main control unit deducts corresponding test channel line resistance again after averaging to above-mentioned positive and negative resistance value, just can get rid of directed superposition electromotive force and test channel line resistance interference, this test result is delivered to the correspondence position display of display unit by main control unit again;
Step 8: repeat step 2 ~ step 7, until complete all test items;
Step 9: whether main control unit is qualified and show according to the test result automatic decision product of all test items, user determines whether this test data is saved in storage unit by push-button unit.
As mentioned above, the automatic low-resistance measurement device of one of the present invention, has following beneficial effect:
(1) can realize automatic test after product access proving installation, testing efficiency is high, can reduce manpower, equipment cost and avoid survey, test leakage by mistake;
(2) automatically eliminate the interference of equipment line resistance in test process, test result is more accurate;
(3) in test channel commutation circuit, realize hardware interlock by CPLD, namely after main control unit output chip code selection, only have one group of unique switch module action, when ensureing fire-working article test, multiple loop can not be had simultaneously, improve testing reliability;
(4) can show test data in real time and automatic decision test result, test data can be saved in storage unit in the specific format, and it is convenient to read, and can meet the informationalized requirement of priming system quality management.
Accompanying drawing explanation
Fig. 1 is overall block-diagram of the present invention;
Fig. 2 is the structural representation of preferred embodiment of the present invention;
Fig. 3 is the structural drawing of Fig. 2 breaker in middle module K1;
Fig. 4 is the structural drawing of signal conditioning circuit in Fig. 2.
Embodiment
Below in conjunction with accompanying drawing, most preferred embodiment of the present invention is further described.A kind of low resistance proving installation automatically, as illustrated in fig. 1 and 2, it comprises main control unit 1, constant current source module 2, test channel cut road circuit 3, signal conditioning circuit 4, analog to digital conversion circuit 5, push-button unit 6, display unit 7 and storage unit 8.
Described test channel commutation circuit 3 is made up of CPLD and switch module, and every root lead-in wire of product is all connected respectively to anode test point TEST1 and negative terminal test point TEST2 by two switch modules.As shown in Figure 3, this module comprises triode Q1, resistance R101, resistance R102 and normally opened relay FR to described switch module structure.The triode Q1 conducting when corresponding drive singal CPLD_S1 is high level, relay closes because coil has current flowing, and the level state of CPLD drive singal is determined by the sheet code selection of main control unit 1.
Described signal conditioning circuit 4 comprises filtering circuit and differential amplifier circuit, and as shown in Figure 4, described filtering circuit is RC passive filter circuit, is made up of electric capacity C50, C51, C52 and resistance R108, R109; Described differential amplifier circuit comprises difference instrument amplifier AD620 and precision resister R110, and the enlargement factor of differential amplifier circuit is determined by resistance R110; The voltage signal at TEST1 and TEST2 two ends after the filtering of RC passive filter circuit, then outputs to analog to digital conversion circuit 5 by after AD620 differential amplification.
Analog-digital conversion circuit as described 5 adopts ADS1243 chip solution, and this chip is connected with main control unit 1 by SPI interface; Under the control of main control unit 1, ADS1243 can gather the voltage signal U2 at the voltage signal U1 after signal conditioning circuit 4 filtering, differential amplification and the known high precision inspection leakage resistance R111 two ends of resistance, and is delivered to main control unit 1 and carry out subsequent treatment.
Described push-button unit 6 adopts the 4*4 keypad of serial communication.
Described display unit 7 adopts DMG80480T070_01W industry serial ports display screen.
Described storage unit 8 adopts SD card storage scheme, and it is communicated with main control unit 1 by SPI interface, and utilizes FATFS file system to manage SD card.
Described main control unit 1 adopts STM32F103ZET6 single-chip microcomputer.
Its concrete steps are as follows:
Step one: after system initialization, to be connected short-circuiting cable by serial ports display screen prompting user and carries out self-inspection, calculates and the line preserving each test channel hinders in process of self-test;
Step 2: the switch module that main control unit 1 exports positive test passage sheet code selection according to corresponding test item controls correspondence again to CPLD, CPLD closes, and correspondence lead-in wire is received anode test point TEST1 and negative terminal test point TEST2 respectively; As shown in Figure 2, if test item is the loop resistance of Line1 to Line2, during forward resistance test, switch module K1 and K4 closes, the electric current that in constant current source module 2, high precise current source exports flows through TEST1, K1, product to be measured, K4, TEST2, high precision inspection leakage resistance R111 successively under the control of main control unit 1, then arrives the ground of constant current source;
Step 3: the port voltage (voltage of TEST1, TEST2 end) in gating loop is delivered to AD620 again and carried out differential amplification after the filtering of RC passive filter circuit, and the signal after amplification delivers to AD1243;
Step 4: under the control of main control unit 1, ADS1243 gathers the voltage signal U2 at the above-mentioned voltage signal U1 that crosses through differential amplification and high precision inspection leakage resistance R111 two ends, and by SPI interface, result is delivered to main control unit 1;
Step 5: single-chip microcomputer utilizes formula:
Calculating resistance value R1, obtain forward resistance value, in formula: A is the enlargement factor of differential amplifier circuit, is the resistance of high precision inspection leakage resistance R111;
Step 6: main control unit 1 test item according to step 2 exports the sheet code selection CPLD of negative testing passage, now switch module K2 and K3 closes, the output current of high precise current source flows through TEST1, K3, product to be measured, K2, TEST2, high precision inspection leakage resistance R111 successively under the control of main control unit 1, arrive the ground of constant current source again, repeat the calculating that step 3 ~ step 5 completes back resistance resistance;
Step 7: main control unit 1 aligns, reverse resistance is averaged, and deduct the resistance of test access line, then this test item resistance value is sent to the correspondence position display of serial ports display screen;
Step 8: repeat step 2 ~ step 7, until complete all test items;
Step 9: main control unit 1 is according to the test result automatic decision of all test items and whether show product qualified and show, and user can determine whether this test data be saved in SD card with text formatting by push-button unit 6.
Claims (5)
1. an automatic low resistance proving installation, it mainly comprises main control unit (1), constant current source module (2), test channel cut road circuit (3), signal conditioning circuit (4), analog to digital conversion circuit (5), push-button unit (6), display unit (7) and storage unit (8), it is characterized in that sheet code selection control test channel commutation circuit (3) that described main control unit (1) successively exports positive and negative test channel according to corresponding test item switches, make the output current of constant current source module (2) that the priming system loop be strobed can be flowed through; Signal conditioning circuit (4) carries out filtering and differential amplification to the port voltage being strobed loop; Analog to digital conversion circuit (5) gathers relevant voltage signal and delivers to main control unit (1) and calculates, and obtaining the resistance value of tested item under different directions measuring current, obtaining the test result of this test item by averaging; Main control unit (1) repeats according to presetting testing sequence the test item that above-mentioned steps completes other, realizes the automatic test to priming system resistance.
2. the automatic low resistance proving installation of one according to claim 1, is characterized in that described main control unit (1) is for STM32F103ZET6 single-chip microcomputer.
3. the automatic low resistance proving installation of one according to claim 1, is characterized in that described display unit (7) is for DMG80480T070_01W industry serial ports display screen.
4. the automatic low resistance proving installation of one according to claim 1, is characterized in that described test channel is cut road circuit (3) and comprised CPLD and switch module; Described switch module is primarily of normally opened relay FR, triode Q1 and divider resistance R102, R103 composition.
5. the automatic low resistance proving installation of one according to claim 1, is characterized in that described signal conditioning circuit (4) comprises filtering circuit and differential amplifier circuit; Described filtering circuit is primarily of electric capacity C50, C51, C52 and resistance R108, R109 composition; Described differential amplifier circuit forms primarily of difference instrument amplifier U19 and precision resister R110.
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| CN201510509669.8A CN105158575A (en) | 2015-08-19 | 2015-08-19 | Automatic low resistance test device |
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| CN201510509669.8A CN105158575A (en) | 2015-08-19 | 2015-08-19 | Automatic low resistance test device |
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Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105675991A (en) * | 2016-01-07 | 2016-06-15 | 北京电子工程总体研究所 | Universal tester for testing fire work equipment |
| CN106018966A (en) * | 2016-03-30 | 2016-10-12 | 中国人民解放军军械工程学院 | Missile initiating explosive device automatic testing device |
| CN106370962A (en) * | 2016-08-18 | 2017-02-01 | 上海机电工程研究所 | Cased bomb initiating explosive device's conduction test and its test method |
| CN106990292A (en) * | 2017-05-26 | 2017-07-28 | 北京航天新风机械设备有限责任公司 | A kind of fire-working article test circuit |
| CN108132386A (en) * | 2016-11-30 | 2018-06-08 | 北京航天计量测试技术研究所 | A kind of 10km long ranges low-resistance TCH test channel expansion system and method |
| CN108152594A (en) * | 2018-01-29 | 2018-06-12 | 中国工程物理研究院电子工程研究所 | A kind of constant-current source tester |
| CN108710077A (en) * | 2018-08-07 | 2018-10-26 | 中科芯集成电路股份有限公司 | A kind of electronic device of test circuit break-make |
| CN109001538A (en) * | 2018-10-10 | 2018-12-14 | 格物感知（深圳）科技有限公司 | A method of reaching high-acruracy survey resistance using non-accurate device |
| CN109283395A (en) * | 2018-11-30 | 2019-01-29 | 中国科学院上海微系统与信息技术研究所 | A kind of multichannel resistance test system and its test method |
| CN109444607A (en) * | 2018-12-17 | 2019-03-08 | 江南机电设计研究所 | A kind of fire-working article test equipment and its test method |
| CN110221127A (en) * | 2019-06-21 | 2019-09-10 | 江西洪都航空工业集团有限责任公司 | A kind of test method of protective resistance |
| CN113671255A (en) * | 2021-07-30 | 2021-11-19 | 哈尔滨工业大学 | Measuring point configurable integrated missile-borne initiating explosive device resistance measuring system |
| CN114624517A (en) * | 2022-03-09 | 2022-06-14 | 国家海洋技术中心 | General resistance, voltage and frequency signal acquisition module |
| CN116754842A (en) * | 2023-02-23 | 2023-09-15 | 中国南方电网有限责任公司超高压输电公司曲靖局 | Harmonic impedance measurement system and method |
| CN108152594B (en) * | 2018-01-29 | 2024-04-19 | 中国工程物理研究院电子工程研究所 | Constant current source tester |
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Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105675991A (en) * | 2016-01-07 | 2016-06-15 | 北京电子工程总体研究所 | Universal tester for testing fire work equipment |
| CN106018966B (en) * | 2016-03-30 | 2019-01-08 | 中国人民解放军陆军工程大学 | Guided missile priming system automatic testing equipment |
| CN106018966A (en) * | 2016-03-30 | 2016-10-12 | 中国人民解放军军械工程学院 | Missile initiating explosive device automatic testing device |
| CN106370962A (en) * | 2016-08-18 | 2017-02-01 | 上海机电工程研究所 | Cased bomb initiating explosive device's conduction test and its test method |
| CN106370962B (en) * | 2016-08-18 | 2019-06-04 | 上海机电工程研究所 | Case bullet priming system continuity test equipment and its test method |
| CN108132386A (en) * | 2016-11-30 | 2018-06-08 | 北京航天计量测试技术研究所 | A kind of 10km long ranges low-resistance TCH test channel expansion system and method |
| CN106990292A (en) * | 2017-05-26 | 2017-07-28 | 北京航天新风机械设备有限责任公司 | A kind of fire-working article test circuit |
| CN106990292B (en) * | 2017-05-26 | 2024-03-29 | 北京新风航天装备有限公司 | Initiating explosive device testing circuit |
| CN108152594A (en) * | 2018-01-29 | 2018-06-12 | 中国工程物理研究院电子工程研究所 | A kind of constant-current source tester |
| CN108152594B (en) * | 2018-01-29 | 2024-04-19 | 中国工程物理研究院电子工程研究所 | Constant current source tester |
| CN108710077A (en) * | 2018-08-07 | 2018-10-26 | 中科芯集成电路股份有限公司 | A kind of electronic device of test circuit break-make |
| CN109001538B (en) * | 2018-10-10 | 2024-03-22 | 格物感知(苏州)科技有限公司 | Method for achieving high-precision resistance measurement by using non-precision device |
| CN109001538A (en) * | 2018-10-10 | 2018-12-14 | 格物感知（深圳）科技有限公司 | A method of reaching high-acruracy survey resistance using non-accurate device |
| CN109283395A (en) * | 2018-11-30 | 2019-01-29 | 中国科学院上海微系统与信息技术研究所 | A kind of multichannel resistance test system and its test method |
| CN109444607A (en) * | 2018-12-17 | 2019-03-08 | 江南机电设计研究所 | A kind of fire-working article test equipment and its test method |
| CN110221127A (en) * | 2019-06-21 | 2019-09-10 | 江西洪都航空工业集团有限责任公司 | A kind of test method of protective resistance |
| CN113671255A (en) * | 2021-07-30 | 2021-11-19 | 哈尔滨工业大学 | Measuring point configurable integrated missile-borne initiating explosive device resistance measuring system |
| CN114624517A (en) * | 2022-03-09 | 2022-06-14 | 国家海洋技术中心 | General resistance, voltage and frequency signal acquisition module |
| CN116754842A (en) * | 2023-02-23 | 2023-09-15 | 中国南方电网有限责任公司超高压输电公司曲靖局 | Harmonic impedance measurement system and method |
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