Multimeter

digital multimeterdigital multimetersmultitesterDMMmultimetersDMMsHigh-impedance digital or analog voltmetersmulti-meters
A multimeter or a multitester, also known as a VOM (volt-ohm-milliammeter), is an electronic measuring instrument that combines several measurement functions in one unit.wikipedia
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Measuring instrument

instrumentscientific instrumentinstruments
A multimeter or a multitester, also known as a VOM (volt-ohm-milliammeter), is an electronic measuring instrument that combines several measurement functions in one unit.
Multimeter, combines the functions of ammeter, voltmeter and ohmmeter as a minimum.

Voltmeter

Digital voltmetervolt metervoltmeters
Vacuum tube voltmeters or valve voltmeters (VTVM, VVM) were used for voltage measurements in electronic circuits where high input impedance was necessary.
Portable instruments, usually equipped to also measure current and resistance in the form of a multimeter, are standard test instruments used in electrical and electronics work.

Avometer

Avo
Macadie invented an instrument which could measure amperes (amps), volts and ohms, so the multifunctional meter was then named Avometer.
AVOmeter is a British trademark for a line of multimeters and electrical measuring instruments; the brand is now owned by the Megger Group Limited.

Ohmmeter

measuredtwo-terminal (2T) sensing
A multimeter is a combination of a multirange DC voltmeter, multirange AC voltmeter, multirange ammeter, and multirange ohmmeter.
Ohmmeters of this type only ever measured resistance as they could not easily be incorporated into a multimeter design.

Ammeter

microammetermoving coil meterampere-meter
A multimeter is a combination of a multirange DC voltmeter, multirange AC voltmeter, multirange ammeter, and multirange ohmmeter. Analog multimeters use a microammeter with a moving pointer to display readings.
Picoammeters are used for sensitive measurements where the current being measured is below the theoretical limits of sensitivity of other devices, such as Multimeters.

Continuity tester

Continuity tester; a buzzer sounds when a circuit's resistance is low enough (just how low is enough varies from meter to meter), so the test must be treated as inexact.
This led to the term "buzzing out a circuit" (which means to test for continuity) Audible continuity buzzers or beepers are built into some models of multimeter, and the continuity setting is normally shared with the ohmmeter setting.

Shunt (electrical)

shuntshuntsparallel shunt connections
For analog current ranges, matched low-resistance shunts are connected in parallel with the meter movement to divert most of the current around the coil.
If too many lights burn out however, a shunt will also burn out, requiring the use of a multimeter to find the point of failure.

IEEE-488

GPIBHP-IBGeneral-Purpose Instrumentation/Interface Bus
Modern meters may be interfaced with a personal computer by IrDA links, RS-232 connections, USB, or an instrument bus such as IEEE-488.
In the late 1960s, Hewlett-Packard (HP) manufactured various automated test and measurement instruments, such as digital multimeters and logic analyzers.

Voltage divider

voltage divisionloading effectpotential divider
The internal resistance of the coil is decoupled from the selection of the series and shunt range resistors; the series network thus becomes a voltage divider.
A Wheatstone bridge and a multimeter both include voltage dividers.

Crest factor

peak-to-average power ratiopeak-to-average ratioPAPR
A True RMS responding multimeter on the other hand will meet its specified accuracy on AC volts and current with any waveform type up to a specified crest factor; RMS performance is sometimes claimed for meters which report accurate RMS readings only at certain frequencies (usually low) and with certain waveforms (essentially always sine waves).
For example, given a certain digital multimeter with an AC accuracy of 0.03% (always specified for sine waves) with an additional error of 0.2% for crest factors between 1.414 and 5, then the total error for measuring a triangular wave (crest factor = 1.73) is 0.03% + 0.2% = 0.23%.

Banana connector

banana plugbanana plugsbanana jacks
Probes are connected to portable meters typically by shrouded or recessed banana jacks, while benchtop meters may use banana jacks or BNC connectors.
The plugs are frequently used to terminate patch cords for electronic test equipment, while sheathed banana plugs are common on multimeter probe leads.

Parallax

trigonometric parallaxsolar parallaxmotion parallax
A digital multimeter displays the quantity measured as a number, which eliminates parallax errors.
A similar error occurs when reading the position of a pointer against a scale in an instrument such as an analog multimeter.

Electronic test equipment

test equipmentelectronic test instrumenttest
* Electronic test equipment
Multimeter e.g., VOM (Volt-Ohm-Milliammeter) or DMM (Digital Multimeter) (Measures all of the above)

Current clamp

Clamp Meterclamp-on ammetercurrent
Clamp meters clamp around a conductor carrying a current to measure without the need to connect the meter in series with the circuit, or make metallic contact at all.
Clamp meters are used by electricians, sometimes with the clamp incorporated into a general purpose multimeter.

Voltage

potential differenceVvoltages
A typical multimeter can measure voltage, current, and resistance.

Electric current

currentcurrentselectrical current
A typical multimeter can measure voltage, current, and resistance.

Electrical fault

faultfault currentfaults
A multimeter can be a hand-held device useful for basic fault finding and field service work, or a bench instrument which can measure to a very high degree of accuracy.

Major appliance

white goodsdomestic appliancewhitegoods
They can be used to troubleshoot electrical problems in a wide array of industrial and household devices such as electronic equipment, motor controls, domestic appliances, power supplies, and wiring systems.

Power supply

power suppliesPSUpower supply unit
They can be used to troubleshoot electrical problems in a wide array of industrial and household devices such as electronic equipment, motor controls, domestic appliances, power supplies, and wiring systems.

United States dollar

$US$USD
Cheap multimeters can cost less than US$10, while laboratory-grade models with certified calibration can cost more than US$5,000.

Calibration

calibratedcalibratecalibrating
Cheap multimeters can cost less than US$10, while laboratory-grade models with certified calibration can cost more than US$5,000.

Wheatstone bridge

bridge
These were used to measure resistance and voltage by using a Wheatstone bridge, and comparing the unknown quantity to a reference voltage or resistance.

Galvanometer

tangent galvanometernull detectorgalvanoscope
The first moving-pointer current-detecting device was the galvanometer in 1820.

Radio receiver

receiverreceiversRadios
Multimeters were invented in the early 1920s as radio receivers and other vacuum tube electronic devices became more common.

Vacuum tube

vacuum tubestubethermionic valve
Multimeters were invented in the early 1920s as radio receivers and other vacuum tube electronic devices became more common.