How to use a multimeter to measure the voltage of AC contactor A1 and A2 when powered on
Select the AC voltage range of 750V for the multimeter, check the socket position, and place the black probe on com Place the red probe in the V socket, and place the red and black probes on both ends of A1A2 to measure the voltage value
Set the multimeter to the highest gear and lower it according to the display! If pointer type is necessary, the pointer should be in the middle position, such as in digital electronic watches, in order to reduce measurement errors and also to lower it to the appropriate level!
Measure with a multimeter in AC voltage range, 250V range (estimated voltage at 220V) or 500V range (estimated voltage at 380V). Connect two probes to A1A2 terminals to check the reading.
Simple enough to casually ask questions without thinking, first use Ac high gear measurement to see if the result is not satisfactory or not, then use Dc high gear measurement
Simply use a multimeter to set the voltage to 600V and use the probe to measure. AC power does not have positive or negative poles. Use the probe to measure A1 and A2, and it is clear whether there is power or not
First, determine the known voltage of the test terminal. The majority of factory electricity is ≤ 380V AC, while civilian electricity is 220V AC. Set a multimeter to AC 500V and measure directly!
Method for measuring frequency of pointer multimeter
To measure frequency with a multimeter, you can convert the frequency into voltage for measurement. Some new types of pointer multimeters have frequency measurement functions. It should be noted that in order to measure frequency, the measured frequency must be converted into a DC voltage signal to complete the frequency conversion.
Next, we will introduce a frequency measurement method. This method uses a pointer multimeter (a DC millivolt meter with a full range of 200mV) and a frequency/voltage converter. Suspicious measurement of frequencies within the range of 10Hz~20kHz, with a measurement accuracy of up to 2%, and an effective value of the measured frequency signal ranging from 50mV to 10V.
1, Measurement principle
Firstly, use a frequency/voltage converter to convert the measured frequency signal into a DC voltage, and then send it to the 2.5V voltage range. The measurement circuit is shown in the following figure, which mainly includes operational amplifier TL061, CMOS six inverter CD4069, and CMOS timer ICM7555
