ABSTRACT
This chapter provides an overview of the types of equipment used to measure electrical power quantities. Instruments that rely upon the motion of a hand or pointer are referred to as analog instruments. The volt-ohm-milliammeter (vom) is one type of analog instrument. The vom is a multifunction, and multirange meter. All measurement systems have certain basic characteristics. Usually, a specific quantity is monitored, either periodically or continuously. The types of instruments are used when no permanent record of the measured quantity values is needed. However, instruments can be employed that provide a permanent record of the quantity values. The operation of a typical roll-chart recording instrument involves the basic principles. The user should assure that the chart roll has enough paper to last throughout the duration of the time that it is to be used. The watt-hour meter is connected between the incoming power lines and the branch circuits of an electrical power system.
