Browse Definitions :
Definition

voltmeter

Contributor(s): Rob Zombie

A voltmeter, also known as a voltage meter, is an instrument used for measuring the potential difference, or voltage, between two points in an electrical or electronic circuit. Some voltmeters are intended for use in direct current (DC) circuits; others are designed for alternating current (AC) circuits. Specialized voltmeters can measure radio frequency (RF) voltage.

A basic analog voltmeter consists of a sensitive galvanometer (current meter) in series with a high resistance. The internal resistance of a voltmeter must be high. Otherwise it will draw significant current, and thereby disturb the operation of the circuit under test. The sensitivity of the galvanometer and the value of the series resistance determine the range of voltages that the meter can display.

A digital voltmeter shows voltage directly as numerals. Some of these meters can determine voltage values to several significant figures. Practical laboratory voltmeters have maximum ranges of 1000 to 3000 volts (V). Most commercially manufactured voltmeters have several scales, increasing in powers of 10; for example, 0-1 V, 0-10 V, 0-100 V, and 0-1000 V.

An oscilloscope can be used to measure low voltages; the vertical displacement corresponds to the instantaneous voltage. Oscilloscopes are also excellent for the measurement of peak and peak-to-peak voltages in AC and RF applications. Voltmeters for measuring high potential differences require heavy-duty probes, wiring, and insulators.

In computer practice, standard lab voltmeters are adequate because the voltages encountered are moderate, usually between 1 V and 15 V. Cathode-ray-tube (CRT) monitors operate at several hundred volts. A typical lab voltmeter can indicate these voltages, but CRT units should be serviced only by qualified technicians because the voltages are high enough to be lethal.

This was last updated in September 2005

Join the conversation

1 comment

Send me notifications when other members comment.

Please create a username to comment.

Hey, What is the difference between mulitmeters and voltmeters?
Cancel

-ADS BY GOOGLE

File Extensions and File Formats

Powered by:

SearchCompliance

  • compliance audit

    A compliance audit is a comprehensive review of an organization's adherence to regulatory guidelines.

  • regulatory compliance

    Regulatory compliance is an organization's adherence to laws, regulations, guidelines and specifications relevant to its business...

  • Whistleblower Protection Act

    The Whistleblower Protection Act of 1989 is a law that protects federal government employees in the United States from ...

SearchSecurity

  • Cybercrime

    Cybercrime is any criminal activity that involves a computer, networked device or a network.

  • data breach

    A data breach is a confirmed incident in which sensitive, confidential or otherwise protected data has been accessed and/or ...

  • zero-day (computer)

    A zero-day vulnerability, also known as a computer zero day, is a flaw in software, hardware or firmware that is unknown to the ...

SearchHealthIT

SearchDisasterRecovery

  • cloud insurance

    Cloud insurance is any type of financial or data protection obtained by a cloud service provider. 

  • business continuity software

    Business continuity software is an application or suite designed to make business continuity planning/business continuity ...

  • business continuity policy

    Business continuity policy is the set of standards and guidelines an organization enforces to ensure resilience and proper risk ...

SearchStorage

  • business impact analysis (BIA)

    Business impact analysis (BIA) is a systematic process to determine and evaluate the potential effects of an interruption to ...

  • RAID (redundant array of independent disks)

    RAID (redundant array of independent disks) is a way of storing the same data in different places on multiple hard disks to ...

  • dedicated cloud

    A dedicated cloud is a single-tenant cloud infrastructure, which essentially acts as an isolated, single-tenant public cloud.

Close