Usage Methods of Analog Multimeter
Familiar with the panel
(1) Selection of sockets: The red test probe should be connected to the socket marked with a "+" symbol, and the black test probe should be connected to the socket marked with a "-" or "*" symbol. Some multimeters have dedicated sockets for special quantities. When measuring these special quantities, the red test probe should be connected to the corresponding dedicated socket, while the position of the black test probe remains unchanged.
(2) Selection of measurement gear: According to the object being measured, turn the conversion switch to the desired position. Some analog multimeters have two switch knobs on the panel, which need to cooperate with each other to complete the measurement work during use. When selecting gears, special care should be taken as even a slight mistake may damage the instrument panel. Especially when measuring voltage, if the current or resistance mode is selected incorrectly, it will cause serious damage to the meter head, and even burn it out.
(3) Range selection: Select the range based on the estimated value being measured, and the range should be greater than the measured value. When measuring current and voltage, the range selection requirement should be to ensure that the pointer works in the area of 2/3 or more of the full scale value as much as possible to ensure the accuracy of the measurement results. When measuring resistance with a multimeter, try to keep the pointer between (0.1 to 10) times the center scale value. If the approximate range of the measured object cannot be estimated before measurement, the conversion switch should be turned to the position with the maximum range for estimation, and then the appropriate range should be selected for measurement.
(4) Correct reading: There are many scales on the dial of a multimeter, and each scale is marked with the symbol of the measured object. The measurement reading should be based on the measured object and the range, and the value indicated by the pointer should be read on the corresponding scale. In addition, when reading, try to make the line of sight perpendicular to the surface; For analog multimeters equipped with mirrors, the image of the pointer in the mirror should be aligned with the pointer before reading.
Check and adjust before use
(1) Check if the appearance of the multimeter is intact and undamaged. When gently shaken, the pointer should swing slightly left and right freely.
(2) Rotate the conversion switch to check if it switches flexibly and if the indicated range gear is accurate.
(3) Place the multimeter horizontally and perform mechanical zeroing. Rotate the mechanical zero adjustment screw under the dial pointer to align the pointer with the zero line on the left side of the scale.
(4) Ohmic zeroing (electrical zeroing) should be performed before measuring resistance. Place the gear switch in the ohm range and short circuit the two probes to adjust the zero ohm adjuster knob to check the battery voltage in the multimeter. If the pointer cannot point to the 0 line on the right side of the ohm scale during adjustment, the battery should be replaced.
(5) Check if the test probe is plugged in correctly. The black probe should be connected to the negative terminal (-) or the common terminal (*) socket, while the red probe should be connected to the positive terminal (+) socket.
