How does digital multimeter calculate volt.,current,resist.?

[positive_edge]

Digital Multimeter

How does a Digital Multimeter calculate Voltage , Current , Resistance. Can someone suggest a good reference.

 

[preet]

Re: Digital Multimeter

in maximum cases it converts all the things in terms of change voltage,and this voltage is feed to ADC that converts it into digital which then given to display unit.

u must read any instrumentation related book that gives u indepth knowledge.

Regards

 

[IanP]

Re: Digital Multimeter

The principle of every digital multimeter is based on Analog-to-Digtal conversion ..
In all cases (voltage, current or resistance) digital multimeter always measures voltage ( current measurement is based on voltage measurement across a test resistor, resistor measurement will be done by sending test current through this resistor and measuring voltage across it) ..

For basics (with examples) on A/D conversion have a look at:

and supplementary material on resistance measurement:
https://zone.ni.com/devzone/conceptd.nsf/webmain/750286047FD5F38886256E0F00798F52

Regards,
IanP

 

[nand_gates]

Re: Digital Multimeter

Best source of information is the book!
AJ Bouwens, "Digital Instrumentation", Ed. McGraw-Hill.
Its little old book may be out of print but exccelent one on the subject!
Excerpt
Nowadays, an increasing number of electronic measuring instruments are going digital, digital circuitry, digital readout, and digital remote control often being combined in the one instrument. The user of digital equipment has to make the best possible use of the various facilities offered. This book, which deals with these techniques, is divided into three parts. Part 1 "Basic Binary Theory and Logic Circuits," deals with the fundamentals of logic elements. Part 2 "Digital Counters and Timers" discusses the fundamentals of these instruments. Part 3 "Digital Voltmeters and Multimeters," deals with the principle of operation of digital voltmeters (DVMs).