Digital display test pen is a kind of test pen, belonging to electrical and electronic tools, used to test whether the wire is live. The digital display pen body has an LED display, which can read the test voltage numbers intuitively. When measuring the live wire, the lighting circuit, the voltage U=220V between the live wire and the ground, the resistance of the human body is generally small, usually only a few hundred to several thousand ohms, and the resistance inside the test pen is usually about several megohms. The current (that is, the current passing through the human body) is very small, usually less than 1 mA. When such a small current passes through the human body, there is no harm to people, and when such a small current passes through the neon bulb of the test pen, the neon bulb will emit light. .
Instructions on how to use the buttons:
(A key) DIRECT, the direct measurement key (far away from the LCD screen), that is, when using the batch head to directly touch the line, please press this button;
(B key) INDUCTANCE, the induction measurement button (closer to the LCD screen), that is, when using the batch head to sense the contact line, please press this button.
Note: No matter how the electric pen is printed, please recognize that the one that is farther from the LCD screen is the direct measurement key; the one that is closer to the LCD is the sensor key!
This test pen is suitable for direct detection of 12-250v AC and DC and indirect detection of neutral, phase and breakpoints of AC. It can also measure the continuity of non-energized conductors.
Direct detection:
a. The last number is the measured voltage value;
b. When 70% of the high-break display value is not reached, the low-break value is displayed;
c. When measuring direct current, touch the other pole with your hand;
Indirect detection:
Press and hold the B button and move the batch head close to the power cord. If the power cord is charged, the display of the digital display pen will display a high voltage symbol
Breakpoint detection:
Press and hold the B key and move longitudinally along the wire, the point where there is no display in the display window is the breakpoint.
The new digital display test pen can test 12V, 36V, 55V, 110V and 220V. Generally, the point on the top of the test pen is the voltage measurement, and the highest display is the current test voltage value; the bottom is the induction test to detect insulators In the case of circuit breakage, this is based on experience.
Voltage detection:
1. The detection range is AC/DC voltage of 12-250V.
2. Lightly touch the DIRECT button, and the metal front end of the test pen touches the object to be tested. The test pen has five voltage values: 12V, 36V, 55V, 110V and 220V. The last value on the LCD screen is the measured voltage value ( When it does not reach 70% of the high-end display value, the low-end value is displayed).
3. When measuring non-ground direct current, the hand should touch the other electrode (such as positive or negative).
Induction detection:
1. Touch the INDUCTANCE button, and the metal front end of the test pen is close to the object to be detected. If the "high voltage symbol" appears on the display, it means that the object is charged with alternating current.
2. When measuring the disconnected wire, touch the INDUCTANCE button, the metal front end of the test pen is close to the insulating outer layer of the wire, there is a disconnection phenomenon, and the "high voltage symbol" disappears at the breakpoint.
3. Use this function to easily distinguish between zero and phase lines (when measuring parallel lines, increase the distance between lines). Detect microwave radiation and leakage.
Precautions:
The keys do not need to be pressed hard, and the two test keys cannot be touched at the same time during the test, otherwise the sensitivity and test results will be affected.
