Why is it wrong to say that if the pen glows when examined with a tester, the circuit must be electrically active?
The luminosity of the tester (electric pen) can indicate that there is a voltage (60V or more) to ground at the place, but it does not indicate that there must be current. Usually said that there is electricity, refers to the line has a current through, because there is a current when the load can work.
Circuit will have the presence of induced electricity, the neon bubble as long as the voltage exceeds a certain range will be luminous, so the luminous test pen is not necessarily caused by the circuit is electric, but also may be induced electricity. And some electrical appliances will have induced electricity will also cause the tester to glow.
Extended information.
1, the first thing to do before using the power test pen is to calibrate the power test pen to determine the normal function of the power test pen. We can test on a known power supply to check whether the neon bulb glows. We also need to check whether the power test pen is damp or water, to ensure our own safety.
2, before using the electric tester pen into the electric field test, test the place where the voltage is applicable. Do not try to use the electric detection pen to test the voltage higher than the applicable range, in order to avoid danger.
3, with the power test pen, do not use your hand to touch the front end of the power test pen metal probe to avoid electric shock accidents; Use the power test pen must use your hand to touch the end of the power test pen metal sheet or metal hook. If you do not do so, although the neon bulb of the pen does not glow, but because the charged body, the pen, the human body and the earth does not form a circuit, can not correctly determine whether the charged body is electrified, once the misjudgment will be very dangerous.
4, in the bright light of the use of the test pen should pay particular attention to judge the neon bubble test pen is really bright, many accidents are caused by careless and misjudgment, we must be avoided.
5, the use of the power test pen is best to wear insulating shoes, to prevent the problem before it occurs.
6, judge the same-phase electricity or different-phase electricity, must remember that both feet and the ground must be insulated. Both hands of each pen test, whether both pens are bright or only one bright, are the same. Not bright is the same-phase electricity, as long as the light is different phase electricity.
7, the high-voltage equipment with a power test pen for power test, first of all, must strictly implement the operation of the monitoring system, someone to operate at the same time, a person on the side of the monitoring. The operator should be in front, the guardian in the back. The use of electric test pens, must pay attention to the rated voltage and the voltage level of the electrical equipment being measured fit.
8, check the electricity, the operator must put on insulated gloves, wear insulated shoes, in order to prevent contact voltage injury to the human body. The operator should first in the electric equipment on the inspection of the power test pen. Multi-layer lines to carry out electric inspection, to test the low voltage first, and then test the high voltage, to the upper and then the lower layers.
