How to read when clamp ammeter measures current
1. Select gear and range. Turn the switch of the meter to the position of DC current "mA", and select the correct range according to the measured current. If the current is not known, in order to avoid the current being too large and exceeding the range, you can First place the DC current at the highest gear for testing. If the range is too large, then reduce the range until the range is suitable.
2. Connect the circuit in series. When the multimeter measures the current, the test lead must be connected to the current in series, and the red test lead is connected to the high potential end of the circuit, and the black test lead is connected to the low potential end of the current.
3. Reading method:
(1) Correctly select the scale line for reading.
(2) Converted current value: Current value = the number of scales pointed by the pointer × the size of the range / the maximum value of the selected scale.
Second, the use of clamp ammeter should pay attention to the following points:
1. When measuring on the high-voltage circuit, it is forbidden to use wires to connect the clamp ammeter to the meter for measurement. When measuring the current of each phase of the high-voltage cable, the distance between the cable ends should be more than 300mm, and the insulation should be good, and the measurement can only be carried out when it is considered convenient.
2. When observing the timing of the watch, special attention should be paid to maintaining a safe distance between the head and the live part. The distance between any part of the human body and the live body should not be less than the entire length of the clamp watch.
3. When measuring the current of low-voltage fusible fuses or horizontally arranged low-voltage busbars, the fusible fuses or busbars of each phase should be protected and isolated with insulating materials before measurement to avoid interphase short circuit
4. Pay attention to the voltage level of the clamp ammeter when using a high-voltage clamp ammeter, and it is strictly forbidden to use a low-voltage clamp meter to measure the current of the high-voltage circuit. When measuring with a high-voltage clamp meter, it should be operated by two people. Non-duty personnel should also fill in the second work ticket when measuring. They should wear insulating gloves when measuring, stand on insulating mats, and do not touch other equipment to prevent short circuit or grounding.
5. Pull the switch to the maximum range after the measurement of the clamp ammeter to avoid accidental overcurrent during the next use; and it should be stored in a dry room
6. When one phase of the cable is grounded, it is strictly forbidden to measure. Prevent personal safety from being punctured and exploded due to the low insulation level of the cable head.
7. When the clamp meter is measuring, the current of the nearby wires will also affect it, so it is also necessary to pay attention to the equal position of the three-phase wires.
8. Do not operate with electricity during maintenance to prevent electric shock.
