Questions and answers about the digital multimeter
1,What is the buzzer function for?
A: Buzzer function, is an additional function of the multimeter, generally do in the 2KΩ file, generally when measuring the 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 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 the larger and larger, 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 programme, is to find the detection source, and then use it again according to the instructions on the line.
4,How to calibrate the multimeter?
A: multimeter and other measuring instruments, as the same, the factory, the manufacturer is tuned, so if there is no major obvious problems, please do not feel free to adjust the school. Nowadays, the multimeter is generally a voltmeter, so when you want to calibrate other gears, you must first calibrate the DC voltage file, which is the basic file called by the industry, this file is inaccurate, basically, every file, every function (except the resistance file), may be inaccurate. 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 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 line contact ** caused by.
5, how to judge (test) multimeter DC voltage (DCV) is good?
A: Detection, first find the detection source, because we are qualitative plus a little quantitative measurement, so there are many available detection sources, household detection sources are, 1.5V alkaline/carbon batteries (No. 1, No. 5/AA, No. 7/AAA), 1.2V rechargeable batteries, mobile phone chargers, power adapters and so on. When testing, dial the multimeter to the desired DC voltage gear, insert the pen according to the instructions, connect the test source, read the readings on the LCD can be, as long as the measured value, in the nominal voltage or so can be.
PS: repeat, we are qualitative plus a little quantitative measurements, so that you can use these sources, because the voltage of these sources is not very stable, like 1.5V battery, new batteries may reach more than 1.6V, the old batteries may be only a few volts of zero.
