A professional electronics repair technician cannot perform his job correctly without an accurate multimeter. Amateur electronic hobbyists benefit from multimeter use, also. In today's technology-driven world, understanding how electronic circuits function is the key to repairing items as varied as portable video games and large television sets. A multimeter has advantages over other types of meters, such as a voltmeter or an ohmmeter.
Identification and Function
A multimeter combines three separate tools in one housing, which is either portable or sized for a desktop. A multimeter has a voltmeter for testing voltage levels in an electronic circuit. The ammeter records amperage, or current, readings. The ohmmeter helps in troubleshooting broken circuits and verifying continuity, or electrical flow. The convenience of having all three tools within the multimeter allows for quicker troubleshooting and more accurate repair results.
Multimeters are either analogue and digital. An analogue multimeter has a needle display; the digital version shows a numeric display of values. Both multimeters can report only one value at a time. They cannot instantaneously show a circuit's voltage, amperage or resistance; each measurement requires a manual set of the specific value desired.
There is more room for error when using an analogue multimeter. The needle display allows a view of changes over time in an electronic circuit, as opposed to an immediate numerical value from the digital assembly. A digital multimeter is user-friendly, automatically changing value ranges -- such as millivolts to volts -- when the circuit reflects that value. Analogue multimeters must be physically set to a specific value range.
A multimeter's accuracy depends upon the quality of the test leads. The test leads from the multimeter manufacturer are usually thin; they are easily broken within their protective sheaths, causing measurement inaccuracies. Website Hobby Hour recommends purchasing thicker leads, especially to avoid accidental electrocution from thin, broken leads.
Newer digital multimeters have the added feature of computer connectivity. A user interface displays on the computer screen and resembles the multimeter's display of values. Designed for electronic engineers, the computer display allows a view of an electronic prototype's voltage, amperage and resistance values. The engineer can change circuitry as needed to improve project production rates and for better quality control.
Multimeters are easily damaged if used when placed in the wrong measurement setting. Verify that the meter is using the voltmeter setting if measuring circuit power. Any voltage flowing through the multimeter under the ohmmeter setting can damage the internal components.