Q&A on the basics of using a digital multimeter
1、What is the buzzer function for?
A: Buzzer function, is an additional function of the multimeter, generally do in 2KΩ file, generally when measuring resistance value of 50Ω below the line (or resistance), the built-in buzzer sound. This function in practice, the role of a great deal, can improve the measurement of the line through the efficiency of the work, is a necessary function of electronic maintenance.
2, why is the digital multimeter in the 200Ω file short connection does not return to zero?
A: In 200Ω file, due to the line, the instrument internal resistance and contact point resistance, so when shorting, there are some tails is normal, the tails in the use of more and more large, can not be adjusted, but can be scrubbed through the circuit board, tight contact points to reduce the value. Can be in use, first shorted, and note down the value, in the measurement of the subtraction can be.
3、How to make sure the multimeter is good?
A: This is a bigger problem, it is a better method to try each function range. Detection, the first to find the detection source, but the general user is equipped with a standard detection source is not possible, so the general test can be used qualitative plus a little quantitative method to measure. The basic program, is to find the detection source, and then use the instructions once on the line.
4, how to calibrate the multimeter?
A: Multimeter and other measuring instruments, as the same, the factory, the manufacturer is calibrated, so if there is no major obvious problems, please do not feel free to adjust the school. Nowadays, the multimeter, its head is generally a voltmeter, so to calibrate the other gears, we must first adjust the DC voltage file, this file is the industry known as the basic file, this file is out of calibration, basically every file, every function (except the resistance file), may be out of calibration. General multimeter will be set in each function of a potentiometer (such as DC voltage) or multiple potentiometers (such as temperature), there is no set potentiometer (such as resistance). There is a potentiometer is good to do, enter the detection signal, and then directly on the line; no potentiometer, generally will not be out of calibration, in case of inaccuracy, it is possible that the instrument is damaged or caused by poor line contact.
5、How to judge (test) the multimeter DC voltage (DCV) is good?
A: When testing, first find the testing source, because we are qualitative plus a little quantitative measurement, so there are a lot of available testing sources, household testing sources are, 1.5V alkaline/carbon batteries (No. 1, No. 5/AA, No. 7/AAA), 1.2V rechargeable batteries, cell phone chargers, power adapters and so on. Detection, the multimeter will be dialed to the required DC voltage gear, according to the instructions insert the pen, connected to the test source, read the reading on the LCD can be, as long as the measured value, in the nominal voltage or so can be.
