Microcomputer integrated electroprobe

Abstract

This invention relates to a microcomputer integrated electroprobe. Wherein, arranging an insulated shell; in the shell, arranging a feeler lever, a current-limiting resistance, a neon tube with lower end connected to the sample resistances of R2 and R6, a hand-contact electrode VSS connected to the lower ends of two sample resistances through the microcontroller with PBO pin connected to the resistance measuring terminal by R12 and PDO-PD6 pin connected with a digital tube, a cell, a power switch, and a shift switch. This invention can display voltage value, phase and its sequence, frequency, period, etc, and has complete functions.

Description

Technical field: [0001] The invention relates to an electrical measuring instrument, in particular to a microcomputer-integrated electric pen. Background technique: [0002] We know that there are various electric pens in the current market, including neon tube test pens, induction test pens, digital display test pens, disconnection test pens, and phase sequence test pens. It has an active luminous effect, accurate measurement, and clear display. At present, the society has a large amount of it. However, it only uses the light effect of the current to indicate whether the line has electricity, and cannot measure information such as period, frequency, phase, and duty cycle; 2. The liquid crystal digital display electric pen is not suitable for maintenance in dark electric panels because its liquid crystal is a passive light-emitting device. The liquid crystal digital display electric pen can display the voltage value of the tested line, with five levels of 12V, 36V, 55V, 110V...

AI Technical Summary

Problems solved by technology

[0002] We know that there are various electric pens in the current market, including neon tube test pens, induction test pens, digital display test pens, disconnection test pens, and phase sequence test pens. It has an active luminous effect, accurate measurement, and clear display. At present, the society has a large amount of it. However, it only uses the light effect of the current to indicate whether the line has electricity, and cannot measure information such as period, frequency, phase, and duty cycle; 2. The liquid crystal digital display electric pen is not suitable for maintenance in dark electric panels because its liquid crystal is a passive light-emitting device. The liquid crystal digital display electric pen can display the voltage value of the tested line, with five levels of 12V, 36V, 55V, 110V, and 220V For display, this digital display electric pen is fundamentally similar to the above-mentioned neon tube test pen, except that a liquid crystal module with digital display is used instead of the neon tube. It is an analog display technology, and the electric pen can only measure voltage. It is obtained by measuring the current flowing through the electric pen, and then using the law of electrical engineering: voltage U = current I multiplied by resistance R, but the resistance is a variable, because the resistance is equal to the resistance in the electric pen plus the resistance of the human body, plus the resistance of the human body to The sum of the resistance of the ground, the resistance in the electric pen is a constant, but the resistance of the human body, the resistance of the human body to the ground varies greatly, from hundreds of ohms to tens of millions of ohms, which causes the measurement error of the digital display electric pen It is very large, which often causes misjudgment by maintenance personnel. In addition, this digital display pen is only divided into five levels of display, and the distance between the gears is too large to accurately display the specific voltage; In the case of B and C, the electric pens all emit light, which often makes maintenance personnel misjudgment that the three-phase power supply is normal, but in fact the three-phase power supply will have the same phase, lack of phase, and three-phase power unbalanced faults. For these faults, the traditional electric test pen It cannot be measured, because when A, A, and B are in the same phase of the three-phase power supply, the electric pens will all emit light in the same way. If a phase sequence test pen with a "resistance-capacitance phase-shifting network" is used to test, three test pens are needed. It is very inconvenient for the wires to touch the three-phase power supply at the same time. If a single-ended phase sequence tester is used to test, the three-phase power supply A, B, and C must be balanced. If the three-phase power supply is unbalanced, it cannot be measured; 4. A variety of induction pens are sold on the market, which can perform non-contact measurement of charged objects. However, this induction pen has at most two gears. When we use the induction function to detect the position of the broken core of the cable, its sensitivity is too high. For this reason, the electric pen is bright at every position of the cable, and the specific broken core position cannot be found out. This kind of induction electric pen does not have the function of displaying the induced voltage, and we cannot determine the specific broken core position according to the change of the induced voltage.

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