Experience in using clamp ammeters
1. When using a clamp type ammeter, attention should be paid to the voltage level and current value range of the clamp type ammeter. When measuring, insulated gloves and shoes should be worn. When observing numerical values, special attention should be paid to maintaining a sufficient safe distance between the human body and the live parts.
2. When measuring the circuit current, the measurement should be carried out on a wire with an insulation layer, while maintaining a safe distance from other live parts to prevent the occurrence of phase to phase short circuit accidents. It is prohibited to change the current gear during measurement;
3. When measuring the current of low-voltage fuses or horizontally arranged low-voltage busbars, insulation materials should be used to isolate the fuses or busbars between phases to avoid causing short circuits. At the same time, attention should be paid not to touch other live parts.
4. Before measurement, the rubber insulation of the clamp shaped iron core should be checked for completeness and damage. The jaws should be clean, rust free, and there should be no obvious gaps after closure.
5. When measuring, the magnitude of the measured current should be estimated first and an appropriate range should be selected. If it is impossible to estimate, you can first select a larger range, then reduce it step by step and switch to the appropriate gear. When changing the range gear, it must be done without power or with the jaws open to avoid damaging the instrument.
6. When measuring, the measured wire should be placed in the middle of the jaws as much as possible. If there is any noise on the joint surface of the jaws, it should be reopened and closed again. If there is still noise, the joint surface should be treated to ensure accurate readings. Additionally, it is not allowed to clamp two wires simultaneously.
7. When measuring a current below 5A, in order to obtain a more accurate reading, if conditions permit, the wire can be wound multiple times and placed in the clamp for measurement. The actual current value should be the instrument reading divided by the number of wires placed in the clamp.
8. Before and after each measurement, the switch for adjusting the current range should be placed in the high gear position to avoid damaging the instrument during the next use due to measurement without selecting the range.
9. The on duty personnel should use a clamp type ammeter for measurement work on the high-voltage circuit, which should be carried out by two people. When non on duty personnel are measuring, the second type of work ticket should be filled out.
10. When measuring on a high-voltage circuit, it is strictly prohibited to connect wires from a clamp ammeter to another meter for measurement.
11. If the barrier needs to be removed during measurement, it should be carried out immediately after the barrier is removed. After the work is completed, the barrier should be immediately restored to its original position.
12. When using a clamp type ammeter, attention should be paid to the voltage level of the clamp type ammeter. When measuring, insulation gloves should be worn, standing on insulation pads, and other equipment should not be touched to prevent short circuits or grounding. When observing the timing of the watch, special attention should be paid to maintaining a safe distance between the head and the live part.
13. When measuring the current of low-voltage fusible fuses and horizontally arranged low-voltage busbars, each phase of the fuse and busbar should be protected and isolated with insulation materials before measurement to avoid causing inter phase short circuits. At the same time, attention should be paid not to touch other live parts.
14. When measuring the current of each phase of high-voltage cables, the distance between the cable heads should be at least 300mm, and the insulation should be good. Only when the measurement is convenient can it be carried out. When one of the three phases is grounded, measurement is strictly prohibited.
15. The clamp type ammeter should be stored in a dry room and wiped clean during use
