The digital dual-clamp phase meter is a high-precision, low-cost, portable, dual-channel input measuring instrument specially designed for on-site measurement of voltage, current, and phase. With this instrument, it is easy to measure the phase between U-U, I-I, and U-I on site, determine inductive and capacitive circuits and the phase sequence of three-phase voltages, detect transformer connection groups, test secondary circuits and bus differential protection systems, read the phase relationship between CTs in each group of differential protection, and verify whether the wiring of electric energy meters is correct. The clamp-type current transformer is used to convert the input of the measured current, so there is no need to disconnect the measured line during measurement. When measuring phase, the two input circuits are completely insulated and isolated, thus completely avoiding possible short circuits in the measured line caused by incorrect wiring, which could damage the measuring instrument. The display uses a high-contrast liquid crystal display with a character height of up to 25mm, and the screen angle can be freely adjusted by about 70° to achieve the best visual effect. The instrument housing is made of engineering insulating materials, and is equipped with a rubber anti-vibration protective sleeve and a portable waterproof cloth bag, making it safe and reliable. When measuring phase within the current range of 10mA-10A and voltage range of 3V-500V, there is no need to disconnect the circuit or change the range. Rotate the switch to the 500V range corresponding to parameter U1, and input the measured voltage from the U1 jack for measurement. If the measured value is less than 200V, you can directly rotate the switch to the 200V range corresponding to U1 for measurement to improve measurement accuracy. The two channels have completely identical voltage testing characteristics, so you can also rotate the switch to the range corresponding to parameter U2 and input the measured voltage from the U2 jack for measurement. Rotate the switch to the 10A range corresponding to parameter I1, connect the output lead of the clamp-type current transformer labeled 1# to the jack, and clamp the jaws onto the measured line for measurement. Similarly, if the measured value is less than 2A, you can directly rotate the switch to the 2A range corresponding to I1 for measurement to improve accuracy. When measuring current, you can also rotate the switch to the range corresponding to parameter I2, connect the measuring clamp labeled 2# to the I2 jack, and clamp its jaws onto the measured line for measurement. When measuring the phase angle between two voltages, to measure the phase angle by which U2 lags U1, rotate the switch to parameter U1U2. During measurement, you can rotate the switch clockwise at any time to the ranges of parameter U1 to measure the U1 input voltage, or counterclockwise to the ranges of parameter U2 to measure the U2 input voltage. Note: When measuring phase, the symbols U1, U2 next to the voltage input jacks and the red "*" symbol on the clamp-type current transformer indicate the same-name ends of the phase. When measuring the phase angle by which I2 lags I1, rotate the switch to parameter I1I2. Similarly, during measurement, you can rotate the switch clockwise at any time to the ranges of parameter I1 to measure the I1 input current, or counterclockwise to the ranges of parameter I2 to measure the I2 input current. Input voltage from U1, use the 2# measuring clamp to input current from I2, rotate the switch to parameter U1I2, and measure the angle by which current lags voltage. During testing, you can rotate the switch clockwise at any time to the ranges of parameter I2 to measure current, or counterclockwise to the ranges of parameter U1 to measure voltage. You can also input voltage from U2, use the 1# measuring clamp to input current from I1, rotate the switch to parameter I1U2, and measure the angle by which voltage lags current. Similarly, during measurement, you can rotate the switch at any time to measure the value of I1 or U2. Rotate the switch to the U1U2 position. For three-phase three-wire connection, connect phase A to the U1 jack, phase B to the ± jack corresponding to U1 and the ± jack corresponding to U2, and phase C to the U2 jack. If the measured phase value is around 300°, the system under test is in positive phase sequence; if the measured phase is around 60°, the system under test is in negative phase sequence. In another measurement method, connect phase A to the U1 jack, output current amplifier of line interface circuit - Yangzhou Dairui Electric..., connect phase B to the ± jack corresponding to U1 and the U2 jack, and phase C to the ± jack corresponding to U2. At this time, if the measured phase value is 120°, it is positive phase sequence; if the measured phase value is 240°, it is negative phase sequence. Corporate Culture, rotate the switch to the U1U2 position. Connect phase A to the U1 jack, and connect the neutral wire to the ± jacks of both input circuits simultaneously. If the phase display is around 120°, it is positive phase sequence; if the phase display is around 240°, it is negative phase sequence. Rotate the switch to the U1I2 position. Connect the load voltage to the U1 input terminal, and connect the load current through the measuring clamp to the I2 jack. If the phase display is in the range of 0° to 90°, the load under test is inductive; if the phase display is in the range of 270° to 360°, the load under test is capacitive. If you need to adjust the display screen angle, press the lock button above the display screen with your finger, and flip out the display screen to rotate it to the most suitable viewing angle. When the low battery indicator appears on the LCD screen, it indicates that the battery power is insufficient, and the battery should be replaced. When replacing the battery, be sure to disconnect the input signal and turn off the power. Remove the screws on the back cover, take off the back cover, and then replace the battery. Under the rated working conditions described in 2.1, the rated working deviation limits of each measured quantity shall not exceed twice the corresponding basic deviation limits. Between the voltage input terminal and the housing, between the iron core of the clamp-type current transformer and the clamp handle and the secondary winding lead, and between the two voltage input terminals, they can withstand a test of 500V/50Hz sinusoidal AC voltage for 1 minute.