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A force gauge (also called a force meter) is a measuring instrument used to measure forces. Applications exist in research and development, laboratory, quality, production and field environment. There are two kinds of force gauges today: mechanical and digital force gauges. Force Gauges usually measure pressure in stress increments and other dependent human factors. [1]
A common mechanical force scale, known as the spring scale, features a hook and a spring that attach to an object and measure the amount of force exerted on the spring in order to extend it. [2]
An example of an electrical force gauge is an "electronic scale".
One or more electrical load cells (commonly referred to as "weigh bars") are used to support a vertical or horizontal "live load" and are solid-state potentiometers which have variable internal resistance proportional to the load they are subjected to and deflected by. As the load and deflection increase, the internal current path circuit which the "supply voltage" from the "scale head" control/display unit must travel increases in length and resistance. At "no load" the resistance and resulting voltage drop are near "zero" and the "signal voltage" returning from the cell to the "scale head" is at or near "supply voltage" sent to it. As load is added and deflection increases, the internal conductor is "stretched" creating a longer, thinner current path with increasing internal resistance. The "signal voltage" is reduced as a result and the "scale head" - whether "analog" or "digital" - will show the increase in load as an increase in weight. Multiple weigh bars are always required and can be used "between" a load and a "cart" under it to make a "portable scale" or the bars can be used as actual "axles" to support a wheeled or tracked cargo wagon/trailer/cart as well as to measure "tongue weight" so even if part of the load is supported by a "tow vehicle" an accurate measurement and record of cargo loaded onto and/or off of the "mobile scale" is possible.
The same type of "weigh bar" can be used to measure horizontal loads and "drawbar pull" of wheeled/tracked or vehicles or "bollard pull" of boats or the "thrust" of jet engines when a proper "test rig" is designed and constructed to provide "frictionless" fore-aft movement of the load relative to the weigh bars.
So-called "strain gauges" which are also electrical "load cells" but which have internal mechanical components and/or combine the "scale head" and/or "power supply" into one unit and permit the use of relatively common, inexpensive and easily "serviced" vertical weigh bars and in a horizontal load situation in a "compact" and "cheap" alternative to the "frictionless" multi-cell custom-made "test rig" as well as those used in/on modern crane "lift computers" are often used as and referred to as "load cells" when in fact in every case the actual "load cell" is in and of itself "useless" without a "scale head" and properly engineered, designed and constructed "test rig" which allows it to convert "live loads" and a supply or "reference" voltage to varying output signal voltages as its "strained".
Load cells do NOT internally "generate" or otherwise "create" electrical "signals" are no "piezo-electric" devices and do not do anything but deflect and create varying voltage "signals" based upon electrical current supplied to them whether by a "display" or the scale head in actual operation or an analog volt-ohmmeter or digital multimeter when "bench tested" or otherwised demonstrated "operating" but not "in operation".
An ammeter is an instrument used to measure the current in a circuit. Electric currents are measured in amperes (A), hence the name. For direct measurement, the ammeter is connected in series with the circuit in which the current is to be measured. An ammeter usually has low resistance so that it does not cause a significant voltage drop in the circuit being measured.
Pressure measurement is the measurement of an applied force by a fluid on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressure and vacuum. Instruments used to measure and display pressure mechanically are called pressure gauges,vacuum gauges or compound gauges. The widely used Bourdon gauge is a mechanical device, which both measures and indicates and is probably the best known type of gauge.
Voltage, also known as electric pressure, electric tension, or (electric) potential difference, is the difference in electric potential between two points. In a static electric field, it corresponds to the work needed per unit of charge to move a test charge between the two points. In the International System of Units (SI), the derived unit for voltage is the volt (V).
A voltmeter is an instrument used for measuring electric potential difference between two points in an electric circuit. It is connected in parallel. It usually has a high resistance so that it takes negligible current from the circuit.
A galvanometer is an electromechanical measuring instrument for electric current. Early galvanometers were uncalibrated, but improved versions, called ammeters, were calibrated and could measure the flow of current more precisely.
An ohmmeter is an electrical instrument that measures electrical resistance. Multimeters also function as ohmmeters when in resistance-measuring mode. An ohmmeter applies current to the circuit or component whose resistance is to be measured. It then measures the resulting voltage and calculates the resistance using Ohm’s law .
A multimeter is a measuring instrument that can measure multiple electrical properties. A typical multimeter can measure voltage, resistance, and current, in which case can be used as a voltmeter, ammeter, and ohmmeter. Some feature the measurement of additional properties such as temperature and capacitance.
An uninterruptible power supply (UPS) or uninterruptible power source is a type of continual power system that provides automated backup electric power to a load when the input power source or mains power fails. A UPS differs from a traditional auxiliary/emergency power system or standby generator in that it will provide near-instantaneous protection from input power interruptions by switching to energy stored in battery packs, supercapacitors or flywheels. The on-battery run-times of most UPSs are relatively short but sufficient to "buy time" for initiating a standby power source or properly shutting down the protected equipment. Almost all UPSs also contain integrated surge protection to shield the output appliances from voltage spikes.
A transducer is a device that converts energy from one form to another. Usually a transducer converts a signal in one form of energy to a signal in another. Transducers are often employed at the boundaries of automation, measurement, and control systems, where electrical signals are converted to and from other physical quantities. The process of converting one form of energy to another is known as transduction.
A strain gauge is a device used to measure strain on an object. Invented by Edward E. Simmons and Arthur C. Ruge in 1938, the most common type of strain gauge consists of an insulating flexible backing which supports a metallic foil pattern. The gauge is attached to the object by a suitable adhesive, such as cyanoacrylate. As the object is deformed, the foil is deformed, causing its electrical resistance to change. This resistance change, usually measured using a Wheatstone bridge, is related to the strain by the quantity known as the gauge factor.
In electrical engineering, the output impedance of an electrical network is the measure of the opposition to current flow (impedance), both static (resistance) and dynamic (reactance), into the load network being connected that is internal to the electrical source. The output impedance is a measure of the source's propensity to drop in voltage when the load draws current, the source network being the portion of the network that transmits and the load network being the portion of the network that consumes.
A dynamometer or "dyno" for short, is a device for simultaneously measuring the torque and rotational speed (RPM) of an engine, motor or other rotating prime mover so that its instantaneous power may be calculated, and usually displayed by the dynamometer itself as kW or bhp.
A scale or balance is a device used to measure weight or mass. These are also known as mass scales, weight scales, mass balances, and weight balances.
A traction motor is an electric motor used for propulsion of a vehicle, such as locomotives, electric or hydrogen vehicles, or electric multiple unit trains.
A shunt is a device that is designed to provide a low-resistance path for an electrical current in a circuit. It is typically used to divert current away from a system or component in order to prevent overcurrent. Electrical shunts are commonly used in a variety of applications including power distribution systems, electrical measurement systems, automotive and marine applications.
An electronic component is any basic discrete electronic device or physical entity part of an electronic system used to affect electrons or their associated fields. Electronic components are mostly industrial products, available in a singular form and are not to be confused with electrical elements, which are conceptual abstractions representing idealized electronic components and elements. A datasheet for an electronic component is a technical document that provides detailed information about the component's specifications, characteristics, and performance.
A load cell converts a force such as tension, compression, pressure, or torque into a signal that can be measured and standardized. It is a force transducer. As the force applied to the load cell increases, the signal changes proportionally. The most common types of load cells are pneumatic, hydraulic, and strain gauge types for industrial applications. Typical non-electronic bathroom scales are a widespread example of a mechanical displacement indicator where the applied weight (force) is indicated by measuring the deflection of springs supporting the load platform, technically a "load cell".
A piezoelectric sensor is a device that uses the piezoelectric effect to measure changes in pressure, acceleration, temperature, strain, or force by converting them to an electrical charge. The prefix piezo- is Greek for 'press' or 'squeeze'.
A Megohmmeter or insulation resistance tester, also colloquially known as megger, is a special type of ohmmeter used to measure the electrical resistance of insulators. Insulating components, for example cable jackets, must be tested for their insulation strength at the time of commissioning and as part of maintenance of high voltage electrical equipment and installations.
This glossary of electrical and electronics engineering is a list of definitions of terms and concepts related specifically to electrical engineering and electronics engineering. For terms related to engineering in general, see Glossary of engineering.