What should be noted when using a clamp ammeter
1. In order to prevent insulation breakdown and personal electric shock, the voltage of the tested circuit must not exceed the rated voltage of the clamp ammeter, and the current of the high-voltage circuit cannot be measured.
2. Before measurement, check if the instrument pointer is at zero position. If it is not at zero position, it should be adjusted to zero position. At the same time, a rough estimate of the measured current should be made and an appropriate range should be selected. If the measured current cannot be estimated, the clamp ammeter should be placed in the highest gear first, and gradually switched downwards until the pointer is in the middle of the scale.
3. Attention should be paid to the voltage level of the clamp ammeter, and low voltage meters should not be used to measure the current of high voltage circuits to avoid accidents.
4. When measuring, the tested wire should be placed in the center of the clamp. The two sides of the jaw should be well connected. If vibration or collision noise is found, the instrument wrench should be turned a few times or opened and closed again. There is dirt on the jaws, which can be wiped clean with gasoline.
5. After measuring high current, if measuring low current immediately, the jaws should be opened and closed several times to eliminate residual magnetism in the iron core.
6. During the measurement process, the range must not be switched to avoid causing an instantaneous open circuit in the secondary circuit, inducing high voltage and causing insulation breakdown. When it is necessary to change the range, the jaws should be opened first.
7. When measuring in places where it is difficult to read current readings, you can first lock the pointer with a brake and then go to a convenient reading location to read the value.
8. If the tested wire is a bare wire, adjacent phases must be isolated with insulation boards in advance to prevent phase to phase short circuits when the jaws are opened.
9. When measuring currents less than 5A, in order to obtain accurate readings, the wire can be wound a few more times and placed in the clamp for measurement. However, the actual current value is the reading divided by the number of wires placed in the clamp.
10. When measuring, if there are other current carrying wires nearby, the measured value will be affected by the current carrying conductor, resulting in errors. At this time, the clamp should be placed on the side away from other conductors.
11. After each measurement, the switch for adjusting the current range should be set to the highest position to avoid damaging the instrument due to measuring without selecting the range in the next use.
12. A clamp meter with voltage measurement mode should measure current and voltage separately and not simultaneously.
13. When measuring, insulated gloves should be worn and standing on an insulated pad. Pay attention to safety when reading and do not touch other live parts.
14. When using a clamp ammeter, try to stay away from strong magnetic fields as much as possible to reduce the impact of magnetic fields on the clamp ammeter. When measuring small currents, if the range of the clamp ammeter is large, the measured wire can be wound several times inside the clamp ammeter port. The actual current value in the circuit should be the instrument reading divided by the number of turns the wire is wound on the clamp ammeter.
