CN2198610Y

CN2198610Y - Large volume DC current low consumption measurer

Info

Publication number: CN2198610Y
Application number: CN 94213554
Authority: CN
Inventors: 李沐荪
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-06-04
Filing date: 1994-06-04
Publication date: 1995-05-24
Anticipated expiration: 2004-06-04

Abstract

The utility model discloses a large volume DC current low consumption measurer. A two-stage filter circuit which is composed of an inductance coil, a resistance and two electrolytic condenser filters alternating components of the measured inductance, a sensitive micro-amperemeter measures current volume of the DC, and a thermal resistance compensates resistance volume fluctuation generated when the measured circuit changes following the temperature change. The utility model is mainly used for measuring DC current of a high frequency inversion rectifier, having the advantages of low consumption, simple structure, low cost, small size, etc.

Description

Large volume DC current low consumption measurer

The utility model relates to the direct current detection device, and particularly big value DC current low consumption measuring instrument belongs to the electrotechnical measurement technical field.

At present, for the high-frequency inversion rectifying installation, measurement as high-frequency inversion DC welder output current, normally detect with a shunt, because the standard pressure drop of shunt is 75 millivolts, is 200 amperes as electric current to be measured, then consumed power is exactly that 15 watts and heating raise the machine intimate temperature on the shunt, therefore to exist power consumption big for this measuring method, the shortcoming of heating.

The purpose of this utility model is to provide a kind of big value DC current low consumption measuring instrument, has overcome the big shortcoming of the power consumption of above measuring instrument own, be have simple in structure, advantage such as cost is low, and volume is little.

The disclosed measuring instrument of the utility model be with the wave filter filtering by the alternating component on the inductance, measure dc voltage drop on the inductance with microampere meter, promptly draw the DC current values of equipment under test.

Fig. 1 is the utility model circuit theory diagrams.

The utility model is by inductance L₁, resistance R₁、R ₂, thermistor R₃, microampere meter M₁, electrochemical capacitor E₁、E ₂And corresponding housing, the compositions such as binding post, with reference to Fig. 1, inductance L₁With electric capacity E₁And resistance R₁With electric capacity E₂Form respectively the two poles of the earth ac filter circuit, resistance R₂With thermistor R₃Rear and the E of series connection₂Parallel connection, microampere meter M₁Its two ends of cross-over connection, E₁Anodal connecting resistance R₁An end, negative pole meets the measurement terminal of A, R₁Another termination inductance L₁, electric capacity E₁Cross-over connection R₁、E ₂The filter circuit two ends and the inductance coil L that form₁Series connection, its positive pole meets L₁, negative pole connects B measurement terminal, inductance L₁Another termination A measurement terminal, consist of the first-level filtering wave circuit, R₃Be thermistor, be used for compensating the temperature variant resistance value of tested inductance L. The utility model When implementing, R₁And R₂Resistance according to thermistor R₃In the resistance of 25 ℃ of temperature and 70 ℃, and Of Internal Risistance Of A Microampere Meter and full deflection current are chosen. The utility model in implementation process, resistance L₁Value is 60mh, resistance R₁Get 750 Europe, R₂Get 270 Europe, thermistor R₃In the time of 25 ℃, get 10K Europe, get 2K Europe in the time of 70 ℃.

The utility model characteristics are to utilize the alternating component of the tested inductance of the two poles of the earth filter circuit filtering, utilize the temperature variant resistance value of thermistor compensation, and are simple in structure, the little test that is applicable to the high-frequency inversion rectifying installation of power consumption.

Claims

1, a kind of big value direct current low consumption measuring instrument is characterized in that: by inductance L ₁, resistance R ₁, R ₂, microampere meter M ₁, electrochemical capacitor E ₁, E ₂And corresponding housing, compositions such as measurement terminal, wherein resistance R ₁With electric capacity E ₂And inductance L ₁With electric capacity E ₁Form the two-stage filtering circuit, resistance R ₂With E ₂Parallel connection, microampere meter M ₁Its two ends of cross-over connection, E ₁Anodal connecting resistance R ₁An end, negative pole meets B measurement terminal, R ₁Another termination inductance L ₁, electric capacity E ₁Be connected across R ₁, E ₂Two ends, its positive pole meets L ₁, negative pole connects B measurement terminal, inductance L ₂Another termination A measurement terminal;

2, measuring instrument according to claim 1 is characterized in that: also have a thermistor R ₃With R ₂Series connection back and electric capacity E ₂Parallel connection is used for compensation benefit survey inductance and varies with temperature and resistance value.