How to Measure Current with a Clamp Meter?
Thu, Dec 15 by ATO.com
How to use a clamp meter to measure amps?
- Before measuring, the clamp meter should be mechanically zeroed.
- Choose the appropriate clamp meter range, from large to small range adjustment, or look at the nameplate value estimates.
- When using the minimum range of the clamp meter measurement, the reading is not yet obvious, can be measured by the wire around a few turns, the number of turns to the center of the jaws of the turns shall prevail, the reading = the indicated value x range/total bias x number of turns.
- When measuring current, the wire to be measured should be in the center of the jaws, and make the jaws close tightly to reduce the error.
- When the measurement is complete, the clamp meter's changeover switch should be placed at the maximum range. Generally speaking, the clamp meter has a digital display and a pointer display, when measuring approximately the approximate range of the measured current, pay attention to the choice of the clamp meter range, and try to choose the right content to reduce the error. In addition, try to clamp the wire in the middle of the jaws of the clamp meter, if the measured current is too small, you can wind the wire into more than one, and then the measured value divided by the number of roots, but also note that you can not measure the bare wire, to avoid the risk of electric shock. If it is a clamp meter that can measure voltage and other functions, the pencil should be removed when the current is measured. Further, in a three-phase load, the clamp's jaws measure the current of the line, and the clamp of two measures the current of the third.
Can a clamp-on ammeter measure DC?
A clamp-on ammeter is a unique instrument for measuring AC current. It has a current transformer at the front end, which is used for this task through electromagnetic induction.
The clamp-on ammeter cannot test DC currents because there is no alternating magnetic field in DC currents, so no secondary currents are generated in the clamp-on transformer, so the clamp-on ammeter is unable to measure DC currents.
Clamp meter measuring current precautions
- The voltage of the line under test should be lower than the rated voltage of the clamp meter.
- Measuring the current of high-voltage lines, wearing insulated gloves, and insulated shoes, and standing on the insulating mat.
- The jaws should be closed tightly and can not be charged to change the range.
- Before measuring the resistance, the circuit to be tested must be completely discharged and completely isolated from the power circuit.
- If the test pen or power adapter is broken and needs to be replaced, it must be replaced with the same type and the same electrical specifications of the test pen and power adapter.
- Do not use the instrument when the battery indicator indicates that the power is depleted. If the instrument is not used for a long time, please remove the battery and store it.
- Do not store or use the clamp meter in high temperature, high humidity, flammable, explosive, or strong electromagnetic field environment.
- Please use a damp cloth or cleaning agent to clean the clamp meter case, do not use abrasive or solvent.
- When the instrument is wet, please dry it first after storage.