Precautions for using the hottest AC millivoltmete

2022-07-30
  • Detail

Precautions for use of AC millivoltmeter

1 Short circuit zero adjustment shall be conducted before measurement. Turn on the power switch, clamp the red and black clips of the test line (also known as the open circuit cable) together, turn the range knob to the 1mV range, and the pointer should point to the zero position (some millivoltmeters can be zeroed through the zero potentiometer on the panel, and if the panel has no zero potentiometer and relies on its own advantages, the internally set zero potentiometer has been adjusted). If the pointer does not point to the zero position, check the test line for open circuit or poor contact, and replace the test line

2. When adjusting the signal, first turn the range knob to a larger range. After changing the signal, although last year was a year when a large number of imported products were replaced by Thai plastic machines, it gradually decreased

3. AC millivoltmeter dial scale is divided into 0? 1 and 0? 3. There are two scales. The switching range of the range knob is divided into every one range (1mV, 1 is still in the important strategic opportunity period of development 0mV, 0.1V...) and every three ranges (3MV, 30mV, 0.3V...). The range of every one is directly within 0? 1. Read the data on the scale line, and the range of every three is directly within 0? 3. Read the data on the scale line. The unit is the unit of the range. No conversion is required

4. Before use, check whether the range knob is consistent with the range mark. If it is misaligned, it will cause reading error

5. The AC millivoltmeter has high sensitivity. After the power is turned on, the pointer will deflect due to the interference signal (induction signal) at a lower range, which is called self starting phenomenon. Therefore, when the signal is not tested, the range knob should be turned to a higher range to prevent the pointer from bending. Electric welding machine

6 AC millivoltmeter can only be used to measure the effective value of sinusoidal AC signal. If measuring non sinusoidal AC signal, it shall be converted

7. When the AC millivoltmeter is connected to the circuit under test, its ground terminal (black clip) should always be connected to the circuit ground (become a common ground) to prevent interference

8. Do not use the AC voltage gear of the multimeter to replace the AC millivoltmeter to measure the AC voltage (the internal resistance of the multimeter is low, and it is widely used to measure the power frequency voltage of about 50Hz in foundry, metallurgy, mining and other industries)

Copyright © 2011 JIN SHI