Analog Test Instruments 1

Traditional meters used by electricians and technicians for field testing and troubleshooting are analog type. In an analog meter, the magnitude of the property being measured (such as voltage, current, resistance, and illumination) is indicated by a corresponding physical movement of a pointer, needle, or other indicator. Voltage, for example, is shown by the needle of a traditional voltmeter swinging to point at a number on a dial.

Analog meters are generally limited to a single function. The most common types are ammeters, voltmeters, and resistance testers (frequently called meggers in the field, after the name of one of the bestknown brands of resistance tester). In some cases the usefulness of traditional analog electrical test instruments can be extended or modified with special adaptors or sensors; some voltmeters, for example, can also be used to measure temperature.

Today, the different types of single-function analog meters have been largely replaced by digital (computerized) meters that combine many measurement functions within a single compact unit. These digital multimeters (DMMs) are now used for most testing, 1