Clamp Meters

Clamp the single core when performing current measurement through clamp meter, the clamp meter calculates the current by inducing surrounding magnetic fields. If live and neutral wires are measured together, the directions of magnetic fields of both wires will be offset, so the measured current is zero constantly. Please clamp a live wire by the clamp jaw to perform current measurement.

Because the sensitivity of camp jaw is relatively poor and large error will occur when performing measurement of small current through clamp meter with large range. It is recommended to use clamp meter with small range.

For AC current measurement:
It is affected by electromagnetic field. The clamp jaw is designed with hall component (a sensitive device), sensitive with magnetism, heat and mechanical stress to some extents. When the clamp meter is interfered by the electromagnetic field in the measurement environment, the reading will be changed or can not be reset.

For DC current measurement:
After measurement of large current, there will be residual magnetism at the clamp jaw for some time, and the least significant digit will be displayed on the LCD. Please long press REL to reset the reading.

Not same.
For peak measurement: Maintain the MAX/MIN value of pulse signal automatically, the response time of logging MAX/MIN peak value is short (about 250us), a transient value can be measured accurately through this function. Peak voltage and current can be observed at the moment of startup of equipment.
For MAX measurement: It refers to the maximum value within a certain time.

The accuracy can be guaranteed at 10% of the range, for example, if the minimum range at AC current gear of UT211A is 600mA, the minimum current that UT211A can measure will be 60mA.

Low pass filter is built in clamp meter with LPF function, typically, this function is used to measure PWM output signal of frequency converter, the high frequency will be filtered during measurement so as to measure signal of fundamental wave.

For example:
1. The frequency converter will interfere the electric circuit at a high frequency for variable-frequency motor.
2. Be sure that voltage and frequency can be measured accurately for variable-frequency drive.

NCV refers to Non-Contact Voltage Detection.
To detect if AC voltage or electromagnetic field exists, bring the front end of the clamp meter to get close to the measured conductor, if the voltage of electric field is greater than the specified voltage (100V), the buzzer will make sounds and the LED will flash or lights up constantly.

On the condition that the measured equipment is powered off:
Firstly, clamp the measured cable through clamp meter.
Secondly, set the clamp meter to a right gear.
Thirdly, press down INRUSH button.
Last, power on the measured equipment, then the starting current of measured equipment will measured and obtained.
This function is typically used to measure starting current of motor or other inductive loads. UT216C has this function.

As a temperature compensation circuit is designed inside the meter, the ambient temperature will be displayed without the temperature probe connected.

The common cause is that the hall component is damaged, it is recommended to send the product to manufacturer for maintenance.

If the measured voltage is 100V, the actual displayed value will be between 98.8V and 101.2V.

Let low-frequency signal pass and stop high-frequency signal from passing. The cut-off frequency point of low pass filter is 1KHz, while VFC is more suitable for measurement of variable frequency. (Note: 40Hz~400Hz). Application case: The detection of inverter and motor drive.