How to measure resistance with a multimeter, how to measure resistance with a pointer multimeter

How to use a multimeter to accurately measure resistance, select the gear, put the two DC ammeters in direct contact, adjust the zero adjustment resistor so that the needle points to the 0 ohm scale. The needle marking value should fall into the middle of the scale, within the 20%-80% inclination range of the start and end of the full scale.

How a multimeter accurately measures resistors

The whole process of measuring resistor with compass digital multimeter:

1. First select the gear (×1, ×10, ×100, ×1K, etc.), then directly touch the two DC ammeters, adjust the zero adjustment resistor (you can turn the resistor) so that the needle points to the 0 ohm scale. (This step is called "resistor zero adjustment")

2. Connect two DC ammeters to both sides of the resistor to be measured respectively (note that this resistor does not need to be connected to other power circuits), then the resistance value of the resistor is the reading * multiplier.

For example: using the ×100 setting, with the needle pointing at the 20 scale, the result is 20*100=2000 ohms.

Experience in testing resistors with multimeters:

1. Due to the discrete system relationship of the resistor scale; its middle section is relatively finely distributed, so the needle indication value should fall into the middle area of ​​the scale as much as possible, that is, within the 20%-80% gradient range of the full scale, so as to make the measurement more accurate. According to the different tolerance levels of resistors, the reading value and the tolerance resistance value are allowed to have a deviation of ±5%, ±10% or ±20% respectively. If it does not meet the requirements and exceeds the tolerance range, it means that the resistor has changed value.　

2. When testing, especially when measuring resistors with resistance values ​​above tens of k ohms, do not touch the ammeter and the conductive part of the resistor with your hands. The resistor to be tested should be soldered out of the circuit, and at least one end should be opened to prevent other components in the circuit from affecting the test and causing data errors. Although the resistance value of the color ring resistor can be determined by the color disk indication, it is best to use a digital multimeter to measure its actual resistance value when using it.

For the inspection of cement resistors, since they are generally fixed resistors, the method of inspecting cement resistors is exactly the same as that of inspecting general fixed resistors.