What are the technical parameters of a digital multimeter and how does it measure?
1. Resolution, word count, and bit count
Resolution refers to the ability of a multimeter to distinguish small signals during measurement. Knowing the resolution of a multimeter can determine whether it can observe small changes in the measured signal. For example, if the resolution of a digital multimeter on a 4V range is 1mV, it means that it can observe a change of 1mV (1/1000V) when reading 1V.
If you must measure a minimum length of 1/4 inch (or 1 millimeter), then you will not purchase a ruler with a minimum scale of 1 inch (or 1 centimeter). If the normal temperature is 98.6 degrees Fahrenheit, then a thermometer that can only measure whole degrees is of little use. You need a thermometer with a resolution of 0.1 degrees.
The words "bit" and "word" are used to describe the resolution of a multimeter. They can be grouped according to the number of words or digits displayed on a digital multimeter.
A 3 1/2 multimeter can display three whole digits (0 to 9) and one "half digit" (only one "1" is displayed or left blank). A 3 1/2 digit multimeter has a high display resolution of 1999 words. A display resolution of up to 19999 words can be achieved on a 4/4-digit multimeter. Compared to 'bit', using 'character' can more accurately describe the resolution of a multimeter. The resolution of a current 3 and a half bit multimeter may be as high as 3200, 4000, or 6000 words.
For certain measurements, a 3200 word multimeter can provide better resolution. For example, if you want to measure a voltage of 200V or higher, a 1999 word multimeter cannot measure 0.1V. A 32 million meter can display 0.1V when measuring voltages up to 320V. Before exceeding a voltage of 320V, this resolution is the same as that of a more expensive 20000 word multimeter.
