Correct use and precautions of clamp meter
Correct use of the clamp meter: ① Estimate the size of the current to be measured, set the changeover switch to the desired measurement block.
① Estimate the size of the current to be measured and set the changeover switch to the desired measurement block. If you can not estimate the size of the measured current, first use the highest range gear measurement. Then adjust to the appropriate range according to the measurement.
② Hold the clamp handle tightly. Make the jaws open and place the measured wire. In order to reduce the error, the measured wire should be placed in the centre of the clamp jaws
③The jaws should be in close contact, if there is a noise, you can check whether the jaws are clean, or re-open once, and then closed.
④ Measurement of small current below 5A, in order to improve the accuracy of the measurement, where conditions permit, the wire under test can be
When measuring small current below 5A, in order to improve the measurement accuracy, if the condition permits, the wire under test can be wrapped around several times and then put into the jaws for measurement. At this time, the actual current should be the reading of the instrument divided by the number of turns of the wire in the jaws.
⑤ Measurement of small current, the wire can be wound in the jaws of the core a few turns, close the jaws after the reading, the current value on the wire is equal to the reading divided by the number of turns (turns of the calculation: the inside of the jaws of a few lines, counted as a few turns).
⑥ after use, should be dialled to the highest current gear, when there is a table set into the table set, stored in a dry, dust-free, non-corrosive gases and not subject to vibration.
(7) Do not measure high-voltage current, the voltage of the circuit to be measured must not exceed the rated voltage of the clamp meter. Clamp meter can not measure high-voltage electrical equipment.
⑧ measurement process can not be switched gear, in the replacement of the gear before, should first be out of the wire jaws, replace the gear again after the clamp into the jaws of the measurement, in order to prevent the space in the switching gears, resulting in the secondary side of the current transformer open-circuit, resulting in high pressure and endanger the safety of individuals and damage to the ammeter.
(1) The use of clamp ammeter should pay attention to matters
① Measurement should be estimated before the initial measurement of the size of the current, select the appropriate range.
② Measured current-carrying wire should be placed in the centre of the jaws to avoid errors. Measurement of current less wire, in order to improve accuracy, if conditions permit, can also be measured wire more than a few turns, and then put into the jaws of the measurement, the actual current value is equal to the meter reading divided by the number of turns of the wire.
③ measurement process, such as noise, it is the jaws and wire contact is poor, the jaws can be reopened and closed once, if the noise still exists, available gasoline on the jaws to clean and then measure.
(2) Measurement methods
① AC power measurement. Turn the switch to ACA1000A. Keep the switch in relaxed state. Press the trigger to open the jaws, clamp a wire and read the value. If the reading is less than 200A, the switch should be rotated to ACA200A to improve the accuracy of the reading.
② AC and DC voltage measurement. Measure DC voltage, the switch rotated to DCV1000 block, measuring AC voltage, the switch rotated to ACV750V block, keep the switch in a relaxed state. The red pen to the "VΩ" end, the black pen to the "COM" end, and then the red and black pens connected in parallel to the circuit being measured, the value read out for the actual circuit voltage.
Measurement of resistance. Turn the switch to the appropriate range of resistance. Keep the switch in a relaxed state. The red pen is pressed "VΩ" end, the black pen is connected to the "COM" end. Connect the red and black pens to the two ends of the resistor to be measured, and the value read out is the actual resistance value of the resistor to be measured.
Note: When measuring on-line resistance, the line should be disconnected and the capacitor connected to the resistor should be discharged.
④On-off test. Turn the switch to 200Ω, connect the red pen to the "VΩ" end and the black pen to the "COM" end. If the table buzzer sounds, it means that the resistance between the red and black pens is less than 50 ± 2.5Ω.
