CN2080677U - Resistance measurer for 150 a a.micro-ohm micro-ohm magnitude of loop - Google Patents
Resistance measurer for 150 a a.micro-ohm micro-ohm magnitude of loop Download PDFInfo
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- CN2080677U CN2080677U CN 90221493 CN90221493U CN2080677U CN 2080677 U CN2080677 U CN 2080677U CN 90221493 CN90221493 CN 90221493 CN 90221493 U CN90221493 U CN 90221493U CN 2080677 U CN2080677 U CN 2080677U
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- resistance
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- Measurement Of Resistance Or Impedance (AREA)
Abstract
The utility model discloses a device adopting four terminals of the volt-ampere measure to measure the contact resistance or the loop resistance of a high low voltage division and combination electric apparatus (switch). A constant-current source passed through terminals I-[1], I-[2]to the measured electric switch [2] and to the amplifier [3], the numeral indicator [4] directly displays the resistance value of the measured switch, and the numeral indicator [5] directly displays the direct current value generated by the constant-current source [1]. The instrument is characterized in that the continuously adjustable DC constant current of 0-150 ampere can be generated, the current value and the resistance value of the measured electric apparatus can be directly displayed by the numeration indicator, the reading is stable, and the testingh repetitiveness is good.
Description
The utility model belongs to the electrical measuring technical field, particularly a kind of instrument that high and low pressure deciliter electrical equipment (switch) contact resistance or loop resistance are measured.
The loop resistance of deciliter electrical equipment needs more accurate the measurement, in order to avoid loop resistance is too high, cause energy consumption to increase and the galvanic circle temperature rise too high and cause device damage, cause the generation of large area blackout.At present, the measurement of the contact resistance of high-low pressure deciliter electrical equipment or loop resistance is to use double bridge or PCI μ Ω/2 type circuit resistance testers to carry out.The working current of double bridge is too little, and is far apart with the actual rated operational current (more than the hundreds of ampere) of deciliter electrical equipment, so measuring error is very big, has data to show that error is up to 50%.PCI μ Ω/2 type circuit resistance testers, though have 100 peace DC current to provide, this electric current is obtained by the AC power rectification, when voltage ripple of power network, the electric current of this instrument is and then fluctuation also, needs the staff to regulate autotransformer at any time and keeps the stable of 100 peace electric currents.Therefore this electric current is not a Constant Direct Current, so measurement is repeated bad.This instrument electric current Displaying Meter is 1.5 grades of magneto-electric reometers in addition, so institute's measuring resistance numerical precision is not high.
The purpose of the present utility model is non-constant for the electric current that solves PCI μ Ω/2 type circuit resistance testers, and electric current Displaying Meter precision is not high, and shortcoming such as the double bridge measuring error is big.The novel test instrument of being developed, can provide 0～150 peace continuously adjustable direct current steady current, and measuring current and measured resistance numerical value directly show by 3 1/2 figure place word tables.Stable reading is reliable, precision height, the good reproducibility of measurement.
The technical solution of the utility model adopts voltammetry four terminal measuring principles, and its block diagram is shown in figure one (150 peace micro-ohm level circuit resistance tester theory diagram).Provide 100 peace Constant Direct Current electric currents by constant current source (1), through terminal I
1, I
2Be added on the tested device for switching (2), the voltage drop that produces on the switch is proportional to the size of switch resistance, and this pressure drop is from terminal V
1, V
2Last taking-up is exaggerated device (3) amplifies, and amplifier is also made voltage simultaneously---and resistance converts and handles, and is directly shown by the resistance value of slowdown monitoring switch by digital watch (4) at last.The DC current that constant current source (1) produces is carried out the direct demonstration of electric current through sampling, amplification, conversion by digital watch (5).
Constant current source is isolated with compound emitter follower (4 '), feedback signal amplifier (6 ') and major loop (5 ') by the given potentiometer of electric current (1 '), integrating amplifier (2 '), phase shift trigger (3 '), photoelectricity and is formed.Its theory diagram is shown in figure two.
Integrating amplifier (2 ') will be compared by the signal of last given signal of electric current that takes out of the given potentiometer of electric current (1 ') and current feedback signal amplifier (6 ') output, both deviations are carried out integration, its output control phase shift trigger (3 '), the output pulse of phase shift trigger is isolated the bidirectional thyristor that is sent in the major loop (5 ') with compound emitter follower (4 ') through photoelectricity and is carried out phased.
Major loop (5 ') is by transformer, bidirectional thyristor, sample resistance, and full-wave rectifying circuit form.Its circuit theory diagrams are shown in figure three.Bidirectional thyristor is connected to the elementary of transformer, its secondary supply rectification.Rectification output is received outside the instrument, uses for connecing by electricity measurer (2).In rectifying output circuit, also be serially connected with sample resistance R and R ', take out signal from R ' and after amplifier (6 ') amplifies, give integrating amplifier (2 ').Give reometer (5) from R taking-up signal and amplify demonstration.
Owing to adopted the negative feedback of main circuit current, integration is regulated, the accurate voltage stabilizing of given power supply, and sample resistance selects precision resistance for use, so can reach the purpose of steady current well.
Advantage of the present utility model: the first, meet the requirement (this standard recommendation is selected the arbitrary numerical value of 100A between the rated current of tested electrical equipment for use as measuring current) of standard GB 763-74, this instrument can provide the DC stabilization electric current of 0～150 peace.The second, measuring current and directly shown measuring accuracy height (reaching ± 0.2% * reading ± 2 words) by digital watch by the resistance of electricity measurer, scope 0～2000 μ Ω of measuring resistance, the 3rd, the good reproducibility of stable reading, measurement.
Accompanying drawing: figure one, 150 peace micro-ohm level circuit resistance tester
(1) constant current source (2) is by electricity measurer (3) amplifier (4) resistance digital watch (5) current digital table
Figure two, the constant current source theory diagram
The given potentiometer of (1 ') electric current (2 ') integral operation amplifier (3 ') phase shift trigger (4 ') photoelectricity is isolated and compound emitter follower (5 ') major loop (6 ') amplifier
Figure three, major loop basic circuit diagram
(G) bidirectional thyristor (T) transformer (D) full-wave rectifying circuit (R), (R ') sample resistance (2) are by electricity measurer (5) current digital table
Specific embodiment: given power supply is supplied with given potentiometer (1 ') after the voltage stabilizing of two-stage integrated regulator, integrating amplifier (2 ') adopts LM124, feedback signal amplifier (6 ') adopts ICL7650, feedback signal is taken from 0.1 grade of shunt R ', integrating amplifier (2 ') carries out the difference of given current signal and current feedback signal to export after the integral operation, control phase shift trigger (3 '), it adopts a FGK04 integrated circuit, two pulses that this trigger output phase is separated by 180 ° and is mutually symmetrical, isolate for making control circuit and main circuit, adopt a pair of 4N30 photoelectrical coupler that pulse is sent to compound emitter follower (4 '), be added to the control utmost point G of bidirectional thyristor again.Bidirectional thyristor 8A/800V, main-transformer power 0.8KVA, primary voltage 220V, secondary voltage (4～4.5V) * 2, pay square electric current 150A, two diodes of full-wave rectifying circuit adopt 100A/50V, and the ventilation fan cooling is housed in the machine.
Claims (3)
1, a kind of 150 peace micro-ohm level circuit resistance testers that high and low pressure deciliter electrical equipment (switch) contact resistance or loop resistance are measured, it is made of current source [1], voltage amplifier [3], indicator gauge [4], [5], wherein indicator gauge [4] links to each other with voltage amplifier [3], in order to show the resistance of tested device for switching; Indicator gauge [5] links to each other with current source [1], in order to show the current value of current source [1]; Two output terminals at current source [1] have four measuring port, I
1, I
2In order to insert tested device for switching [2]; V
1, V
2Port is drawn the voltage drop on the tested device for switching [2], it is characterized in that: described current source [1] adopts constant current source.
2,150 peace micro-ohm level circuit resistance testers as claimed in claim 1, it is characterized in that: digital wash is all adopted in described indicator gauge (4), (5).
3,150 peace micro-ohm level circuit resistance testers as claimed in claim 1 or 2, it is characterized in that: described constant current source is isolated and compound emitter follower (4 ') by the given potentiometer of electric current (1 '), integral operation amplifier (2 '), integrated phase shift trigger (3 '), photoelectricity successively, and by bidirectional thyristor G main-transformer T, full-wave rectifying circuit D, sample resistance R, R ', measurement terminal I
1, I
2, V
1, V
2The major loop of being formed (5 ') constitutes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 90221493 CN2080677U (en) | 1990-09-27 | 1990-09-27 | Resistance measurer for 150 a a.micro-ohm micro-ohm magnitude of loop |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 90221493 CN2080677U (en) | 1990-09-27 | 1990-09-27 | Resistance measurer for 150 a a.micro-ohm micro-ohm magnitude of loop |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2080677U true CN2080677U (en) | 1991-07-10 |
Family
ID=4899617
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 90221493 Granted CN2080677U (en) | 1990-09-27 | 1990-09-27 | Resistance measurer for 150 a a.micro-ohm micro-ohm magnitude of loop |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2080677U (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1308694C (en) * | 2005-11-03 | 2007-04-04 | 北京科技大学 | Method and device for detecting resistance |
| CN104849566A (en) * | 2015-06-15 | 2015-08-19 | 南京信息职业技术学院 | Portable micro-ohmmeter |
| CN107851857A (en) * | 2015-07-17 | 2018-03-27 | 罗伯特·博世有限公司 | The method of battery unit and the electric current for determining to flow through battery unit |
| CN110927465A (en) * | 2019-11-26 | 2020-03-27 | 深圳供电局有限公司 | Direct current resistance measuring circuit and device |
| CN112834823A (en) * | 2020-12-30 | 2021-05-25 | 江苏大学 | Oxide thin film transistor type resistance measuring meter |
-
1990
- 1990-09-27 CN CN 90221493 patent/CN2080677U/en active Granted
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1308694C (en) * | 2005-11-03 | 2007-04-04 | 北京科技大学 | Method and device for detecting resistance |
| CN104849566A (en) * | 2015-06-15 | 2015-08-19 | 南京信息职业技术学院 | Portable micro-ohmmeter |
| CN107851857A (en) * | 2015-07-17 | 2018-03-27 | 罗伯特·博世有限公司 | The method of battery unit and the electric current for determining to flow through battery unit |
| CN107851857B (en) * | 2015-07-17 | 2020-08-11 | 罗伯特·博世有限公司 | Battery cell and method for determining a current flowing through a battery cell |
| CN110927465A (en) * | 2019-11-26 | 2020-03-27 | 深圳供电局有限公司 | Direct current resistance measuring circuit and device |
| CN110927465B (en) * | 2019-11-26 | 2022-09-02 | 深圳供电局有限公司 | Direct current resistance measuring circuit and device |
| CN112834823A (en) * | 2020-12-30 | 2021-05-25 | 江苏大学 | Oxide thin film transistor type resistance measuring meter |
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|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |