The purpose and usage method of measuring electric pens
In addition to being able to determine whether an object is electrified, the test pen also has the following purposes:
1. It can be used for low-voltage nuclear phase measurement to determine whether any wires in the circuit are in phase or out of phase. The specific method is to stand on an object that is insulated from the ground, hold a measuring pen with both hands, and then test on the two wires to be tested. If the two measuring pens emit very bright light, the two wires are out of phase; On the contrary, it is in phase, which is judged based on the principle that the voltage difference between the two electrodes of the neon bubble in the measuring pen is directly proportional to its luminous intensity.
2. It can be used to distinguish between alternating current and direct current. When using a test pen for testing, if both poles in the neon bubble of the test pen emit light, it is an alternating current; If only one of the two poles emits light, it is direct current.
3. It can determine the positive and negative terminals of direct current. Connect the test pen to a DC circuit for testing, and the electrode with the neon bubble shining is the negative electrode, while the electrode without the neon bubble shining is the positive electrode.
4. It can be used to determine whether the DC is grounded. In a DC system with insulation to ground, standing on the ground can be used to contact the positive or negative poles of the DC system with a measuring pen. If the neon bubble of the measuring pen is not lit, there is no grounding phenomenon. If the neon bubble lights up, it indicates a grounding phenomenon, and if it lights up on the pen * *, it indicates a positive electrode grounding. If it shines on the finger end, it is negative grounding. However, it must be pointed out that in DC systems with grounding monitoring relays, this method cannot be used to determine whether the DC system is grounded.
How to use a test pen:
1. Before testing whether electrical appliances and circuits are live, it is advisable to test them in a charged area to see if the test pen is in good condition to prevent electric shock caused by misjudgment.
2. When holding the pen, press the tail of the measuring pen with your fingers, and hold the pen body with the other fingers.
3. When measuring electricity, the pen tip touches the test body and the hand touches the tail of the measuring pen. If the test body is charged, the neon tube of the test pen will emit light; If the neon tube does not emit light, it indicates that the test body is not charged.
4. The insulated cathode of the measuring pen should not be used if it is less than 1 megohm.
