Views: 6 Author: Vicky Publish Time: 2023-03-31 Origin: Site
As a multi-functional and multi-range measurement device, multimeter is also known as a multiplemeter and three-meter, which can typically measure DC voltage, AC voltage, DC current, resistance, and the equality of audio electricity. There has more functional types that can also measure AC current, capacitance, inductance, and various semiconductor properties.
1. Look at the file before measuring
Check that the switch for the appropriate measurement category and range option is in place each time you take up the pen to get ready for a measurement. We need to make this habit if we want to be safe.
2. Measure the gear without dialing while dial the gear after measuring
In order to prevent creating arcs and damaging the conversion switch contacts, the selection knob cannot be arbitrary dialed while the measurement is taking place, particularly when measuring high voltage (such as 220V) or high current (such as 0.5A). The range option switch should be set to "?" Location after the measurement.
3. The dial must be horizontal and show a positive number.
When reading, the multimeter should be held horizontally with the line of sight confronting the hand.
4. The measuring range should be appropriate, and the needle should be more than half.
Choose the measurement range. If it is impossible to predict the measured size in advance, you should attempt to select a bigger measuring range and then gradually reduce it in accordance with the magnitude of the deflection angle until the pointer deflected to approximately 2/3 of the full scale.
5. Test R should be uncharged while test C should be discharge firstly.
Measuring the resistance at the test circuit's belt point is absolutely prohibited. Electrical equipment's large-capacity capacitors should be short-circuited and monitored before being checked.
6. The gear shift must be set to zero and the R test must be adjusted to zero first.
Before measuring resistance, you should short the two pens, crank the "Ω" zero potentiometer so that the pointer points to zero, and twist the conversion switch to the electrical barrier. The ohm zero point must be altered each time the electrical barrier is changed.
How do we use a multimeter safely?
On the dial's left side, the pointer should be in line with the end line. Inconsistent values should be reset to zero. To prevent an excessive current from damaging the multimeter, it is required to estimate the range of the current and voltage to be measured, set the multimeter in a larger gear at first, and then adjust it to the proper gear.
The impact of the multimeter's resistance should be considered when measuring. For instance, the measured circuit is linked to the meter pen to measure the voltage.
The measured value is currently affected in some way by the current that is currently flowing through the resistance in the multimeter. When measuring the voltage at the same point, if different gears are used, the internal resistance of the multimeter is different, and the degree of impact is also different.
When measuring the transistor electronic circuit, it is better to select the internal resistance of 20kΩ/V by DC. This value is usually marked on the multimeter dial. In addition, the transistor circuit often needs to measure low-value voltage, such as 0.1V. At this time, the selected multimeter should have a measurement range of 1V.