Which probe of the pointer multimeter is connected to the positive pole when measuring DC voltage?
When using a pointer type multimeter to measure DC voltage, the first thing to check is whether the multimeter is good or bad, whether the measurement is accurate, and whether the pointer is sensitive. Insert the red probe into the socket marked with 10. V/Ω "and the black probe into the C0M" socket. Adjust the gear knob to any resistance gear, short-circuit the red and black probes, and turn the pointer to the right to the zero position. Then rotate the zero knob to adjust the pointer to the zero position. If the pointer is at infinity and the short circuited probe does not swing to the right, it is necessary to check whether the fuse inside the meter is melted. If the fuse is normal, the battery inside the meter needs to be replaced. Short circuit the probe pointer in the resistance mode and if it cannot be zeroed, replace the battery inside the meter.
When measuring DC voltage, if the voltage value is known, the knob can be directly adjusted to the corresponding gear of DCV. It is worth mentioning that the closer the gear is to the measured voltage, the more accurate the measured value will be. For example, for 1.5v, choose 2.5v gear, and for 12v24v, choose 50v gear. If the measured voltage is unknown, start from the highest gear, measure and downshift in sequence until the measured voltage is close to the selected gear. Do not measure high voltage in a low gear, as this will cause the pointer to deflect and damage the multimeter easily. Place the multimeter as horizontally as possible during measurement to avoid affecting the accuracy of the measured values.
When reading values, you should refer to the second item in the header labeled ACV The scale line of DCV is counted from left to right, and the resulting value is the actual scale line reading multiplied by the gear value divided by the total scale line, which is the final value. As shown in the above figure 47X (10 ÷ 50) II 9.4 V, this is a newly purchased battery. The measured value is slightly higher than the marked value, indicating that the battery's performance is very good!
