Analog multimeter use method and precautions - Solutions - Huaqiang Electronic Network

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1, the method of use

(1) Zero adjustment. Place the meter horizontally and check if the pointer is at the starting point of the scale. If it is moved, adjust the zero adjuster to return it to the starting point of the scale.

(2) For the measurement of DC voltage, the range selection switch is rotated to the range of the DC voltage “V”, which is required to measure the voltage, and then the current direction must follow the polarity of the mark on the terminal button. The range selection should be as close as possible to the measured amount, so that the pointer has a large deflection angle to reduce the error.

(3) Measurement of AC voltage. The method is similar to DC, and the range selection switch can be rotated to the AC voltage range to be measured. The rated frequency of the AC voltage is measured at 45-1500 Hz, and the frequency is expanded to 5000 Hz. For accurate results, the common * of the meter should be connected to the negative pole of the signal generator (connected to the casing end).

(4) Measurement of DC current. Rotate the range selector switch to the DC current “uA” or “A” range and select it to the current range to be measured. String the meter into the circuit.

(5) Measurement of DC resistance. Rotate the range selector switch to the resistance “Ω” range, short the external circuit, deflect the pointer to the full value, adjust the zero ohm adjuster, make the pointer indicate at the zero ohm position, and then measure. To make the measured value accurate, the ohm scale should be Use the middle section as much as possible.

2, matters needing attention

In order to measure accuracy and prevent damage to the instrument, the following precautions should be observed:

(1) When the instrument is tested, the switch button cannot be rotated. Especially when the voltage is high and the current is high, the live conversion range is strictly prohibited.

(2) When the measured value cannot be determined, the range switch should be turned to the maximum range position, and then the adapted range is selected to maximize the deflection of the pointer.

(3) When measuring DC current, the meter should be connected in series with the circuit under test. It is forbidden to connect the meter across the voltage of the circuit.

(4) When measuring the resistance value of the circuit, the power of the circuit under test should be disconnected. If there is a capacitor in the circuit, it should be discharged and then measured. Do not measure when the circuit is live.

(5) Every time the meter is used, it is better to rotate the range selection switch to the position of 500V AC/DC voltage to prevent the instrument from being damaged by accidentally negligent control of the measurement range.