An output meter is a measuring device that gives an indication of the magnitude of work or energy produced by a device in a relevant unit of measurement. Output meters are used to measure many forms of work or energy, including torque, sound, light, power or electrical outputs. Each different type of output meter features external measuring devices and internal mechanisms relevant for the work or energy involved. Some output meters may be small handheld devices, while others are found permanently mounted on vehicle dashboards, panels or installation instrument consoles. Output meters are often essential diagnostic aids in establishing the overall efficiency of many different types of systems.
The output of most machines, appliances or installations that produce work or energy can be measured using an output meter. The measurement generated is useful for establishing whether or not the particular machine or appliance is functioning correctly. Output meter readings are taken in a wide variety of ways and expressed in application-specific units of measurement. The meters themselves vary considerably in size and design.
For instance, the light output meter is most often a small, portable, handheld device used to gauge light output in photography, industrial or security lighting installation and indoor crop growing. The devices typically consist of a photosensitive cell array that gathers light and expresses the output in lumen, lux or candela on a digital or analog readout. Sound or audio output meters may also be portable devices or permanently built into sound systems or recording and sampling desks. These meters measure the intensity of a system's sound output. The unit of measure used with these meters is usually decibel or sound pressure and volume unit (VU), which is a measure of electrical signal strength.
Electrical power supply outputs are measured in watts and typically displayed on watt output meters built into electrical distribution panels. The power output of internal combustion engines and electric motors is expressed in horsepower (HP) or kilowatt (kW). The measurement method for these machines usually involves a resistance roller arrangement that is turned by the motor or the wheels of an automobile with the readout graphically displayed on a panel or console mounted gauge. The torque output of this type of machine is also measured in a similar fashion and expressed in foot pounds or newton meters.
There are many other types of output meter that measure a variety of system outputs, including air and fluid flow, temperature and pressure. All of these devices use different measurement methods, such as temperature probes, pressure sensors or mechanical flow-activated mechanisms. Output meter readings are not only used to check whether or not single devices are functioning properly, but also as an overall system efficiency guide in applications that feature interdependent elements.