Why do you set the multimeter to zero every time you measure resistance?
Multimeter zero refers to the mechanical table said, in the measurement of resistance every time to adjust zero, if not zero the resistance value is not allowed. Voltage, current is the file is not necessary to adjust zero. If you can not adjust the zero this means that the head of the hairspring some aging, the hairspring of the bad elasticity of the counter, then you can watch the head of the centre of a zero twist, you can gently move the zero twist on it!
Each electronic amateurs can not be less is the multimeter, you said the digital multimeter, it is relying on the action of the pointer of the internal 1.5V battery through the resistor current limitation for the needle action, I dismantled and installed a few pointer table and a lot of head, the root of the pointer connected to the centre of the table head, the centre of a few millimetres in diameter of the magnet wound around a coil on the magnetic column, with the root of the pointer connected to the oil filaments, the other end of the fixed, when the knob! When the knob points to the R file, the red and black pens touch, it gives the coil on the current of a few microamps, the coil is electrified to cut the magnetic lines of force, like a motor-like rotation, can be like a "mosquito coil" oil wire pulled, can only be rotated to fix the 90-degree declination, in the table running angle engraved on the mark, can be made through a variety of designs so that a table respectively adjust the gear can measure AC, DC, voltage, current, resistance, transistor amplification and other functions.
What should I pay attention to when measuring resistance with a multimeter?
(1) The multimeter conversion switch to ohm block.
(2) Select the appropriate range.
(3) Short the two pens and zero.
(4) Contact the measured resistor ends with the two pens, and read the measured resistance value. R = pointer index × range
Measurement of resistance process should pay attention to the following issues.
(1) The measured resistance must be detached from the power supply.
(2) Both hands can not touch the two leads of the resistance at the same time.
(3) The range should be selected appropriately.
