Weighing Terms & Definitions

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A common weighing mode to determine a total "accumulated" weight of multiple samples. After one sample is weighed, the result is stored in memory. The next sample is weighed and can be added to the weight of the first sample to give you the total accumulative weight.

How well a scale can display the weight of a sample relative to the true weight of the sample. This is closely related to the combination of the display resolution and consistency of the performance of the scale.

Common term used for any mechanical or software changes made to a weighing scale usually during calibration.

Related to temperature, humidity and air pressure. Standard environmental conditions at room temperature, which is typically accepted as 70° Fahrenheit.

A type of communication output that represents weight as a continuously variable signal, most commonly 4 to 20 mA or 0 to 10 V. Analog outputs typically send signals to PLCs and other process control equipment.

Analytical balances are typically found in laboratories. They are a class of balance capable of displaying results into the sub milligram range.

Weighing mode for weighing animals. Also referred to as dynamic weighing. Animal weighing takes into consideration movements or shifting of the load commonly associated with an animal moving on the weighing platform during measuring.

National standards, regulations or certifications that weighing equipment is in compliance with.

Stands for Average Piece Weight. Commonly associated with parts counting applications. APW is the determined average weight of an individual piece based on the total weight of a sample divided by the number of pieces weighed.

These are two sets of readings on a calibration report. As-found is what the scale did before the technician touched anything. As-left is what it did after any adjustment.

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Automatic doors are typically motorized draft shield doors on analytical and precision balances. Automatic doors prevent the operator from having to make direct contact with the draft shield doors during operation.

Most commonly used with LCD displays. A backlight is a light that illuminates the LCD display to make it easier to read.

Commonly used interchangeably with scale. Weighing scale or weighing balance. However, many people associate balances with laboratory weighing instruments such as analytical, semi micro, and microbalances.

The platform of a bench scale or weighing scale where samples are weighed. Also commonly referred to as the weighing base or platform. This includes the loadcell or loadcells, frame that holds the loadcells, and the weighing platter or pan.

The process of weighing several ingredients in sequence and putting them into the same container. The scale tracks each addition against a set target weight.

Baud rate is the rate at which information is transferred in a communication channel. In the serial port context, "9600 baud" means that the serial port is configured to transfer 9600 bits per second.

Also known as under hook weighing. Below balance weighing uses an integrated hook in a scale or balance to hang samples from. This is most commonly used with density determination kits.

A weighing system built into a conveyor that measures material as it passes. Belt scales combine belt speed with the load carried on a weighed section of idlers to measure flow rate and a running total. They are often used for bulk material weighing in agricultural and manufacturing applications.

Bench scales are usually compact scales that are used on a bench, or table top, as the name would imply. Often times, bench scales are also referred to as platform scales because it is common for the weighing base to be separate from the indicator. However, single unit compact scales are often referred to as bench scales as well because of their use on a work surface.

A bind is something that physically inhibits the scale from operating properly. Usually it is something that physically touches the weighing mechanism. A common example is when a floor scale is pushed up against a wall. If the scale base is touching the wall it won't be able to move up and down freely.

A binary unit that uses voltage to represent a 0 or 1.

Body Mass Index is calculated from a person's weight and height. Many physician and health scales display it directly once a height is entered.

Also referred to as a draft shield. A breeze break blocks drafts from the weighing chamber which could affect weighing results in three-place gram balances or sub-milligram balances. Even a slight draft from someone passing by can cause the display to fluctuate.

A method for testing large capacity scales when there are not enough certified test weights to reach capacity. A known weight is applied and then substituted with other materials reading the same. For example, instead of a 50 lb weight, a substitute weight could be a 50 lb bag of sand.

The action of verifying and adjusting an instrument using test standards of a known documented weight. Calibrating a scale against test standards ensures that the scale is performing as it should and is accurate to the manufacturer's stated specifications.

The duration of time an instrument or scale goes between calibrations. There is no universal interval. As a general rule of thumb, 1 year is suggested. For scales that are used hard and frequently, it is a good idea to reduce the interval and calibrate more often.

A document that provides as found and as left data pertaining to the accuracy of a weighing scale or balance. Also known as a calibration certificate, a calibration report is typically completed by a certified scale technician, registered scale service agency or ISO accredited lab.

The ability of a system to store an electric charge.

Maximum weight a scale can handle without taking into consideration overload protection if applicable.

A checkweigher is a scale used to verify a selected weight within programmed limits. An operator sets a pre-determined weight and once the desired weight is reached, the checkweighing scale will provide an audible or visible indication to the operator. Checkweighers are commonly used in filling applications where an operator fills and weighs a product to ensure consistent weight.

Checkweighing is the process of verifying the weight of a product based on pre-determined values. Commonly used for filling applications. See "checkweigher" above for more specific applications.

Scales are classified based on the number of scale divisions and the value of the scale division (d or e). Classes are a way of designating intended use for the scale.

Refers to the capability of a scale or balance to connect to and communicate with peripheral devices such as computers, printers, barcode scanners and other devices. Also referred to as the interface, or communication interface.

A scale used for counting parts and pieces. Weight is determined for a sample and saved in the scale. The scale can then calculate how many parts there are on the pan based on the APW and total weight.

Also known as a hanging scale, a crane scale is an overhead weighing scale commonly used in heavy-capacity industrial lifting applications. Often times, crane scales are used in warehouses and production facilities to move heavy objects from one area to another. The crane scale can measure the weight of a load which can be used for quality or logistics purposes.

Creep is a change in the weight reading over time while the load on the scale stays in the same place and the temperature stays the same. Creep is a result of a change in the load cell's spring element and adhesive.

A packet of bits that creates a command, message, or error reading. It usually consists of a thread of 7 or 8 bits.

Deadload is the weight of the weighing structure itself before any product is added. On a hopper or tank scale the deadload includes the vessel, an agitator, piping, valves, etc. Deadload has to be considered when choosing the load cell capacity to make sure it can handle the total weight of everything, not just the material being weighed.

Deflection is the distance a load cell physically moves between no load and rated capacity. This is usually just a few thousandths of an inch. Load cells have to be free to deflect to some degree to measure properly. Too much deflection could result in damage.

Density determination is a method of finding the density of a solid or liquid using a scale or analytical balance. Density determination is often performed using under-hook weighing and a specialized kit. These kits are available as an accessory for any scale model that offers density determination as a weighing application.

A scale that is electronic, not mechanical. Digital scales are the most common weighing scales on the market today. People buy digital scales for a large variety of weighing applications from analytical to heavy capacity. Digital scales are found almost everywhere. People use digital scales at home to weigh themselves for health purposes, delis use them to weigh foods, manufacturers to weigh shipments and the list goes on.

Discrimination refers to how well a digital scale can display the weight of a very small sample or when a sample changes by a very small amount. A test load or change in test load equal to 1.4 divisions is normally used when performing a discrimination test on a digital scale.

A display is where the measurement results are shown. This can be a digital readout like with an LCD display or a beam display on a mechanical scale.

A scale division is commonly interchanged with readability and resolution. A division is the smallest increment of weight that the digital display will show. A division can be determined by taking the scale's capacity divided by the scale's readability.

Also known as a breeze break. A draft shield is typically associated with analytical balances that have a readability of 0.001 grams or better. The draft shield protects the weighing pan from air movement commonly associated with ventilation systems and persons walking by the balance.

Drift is a term used to describe when a digital scale display does not remain steady. The reading on the display will fluctuate up or down. Drift is usually caused by environmental influences such as drafts. Drift can also be caused by defects in the scale.

A scale offering two complete weighing ranges, each with its own capacity and readability. For example, a dual-range balance may read to 0.01 mg up to 60 g and to 0.1 mg up to 220 g.

Dynamic weighing, also often times referred to as animal weighing, is an application that determines weight even when conditions aren't ideal. For example, while weighing an animal, it is likely that the animal will move during the process which can throw off the results. Dynamic weighing application takes this into consideration and is able to determine a weight even in unsatisfactory conditions.

Eccentric loading is when a weight is not placed on the center of the weighing platform. The ability of a scale to display the same value when a weight is placed anywhere on the weighing platform is checked by performing a shift test.

A scale that is partly digital and partly mechanical. Usually these are scale systems where the scale base is mechanical and instead of a mechanical beam display a loadcell is integrated along with a digital weight indicator.

Ethernet is a system for connecting a number of computer systems or devices to a local network. An Ethernet cable is used to form the connection. Some scales offer Ethernet communication ports as a method of connection to software and local networks.

Excitation is the DC voltage the indicator applies across the load cell bridge. This is commonly 5 or 10 volts. Load cell output is proportional to excitation. A load cell rated at 3 mV/V produces 30 millivolts at capacity on 10 volt excitation and 15 millivolts on 5 volt excitation.

A scale with external calibration does not offer an automatic, or internal, calibration feature. The scale must be calibrated using test standards and must be performed by an operator.

Filling is a common application that uses weighing scales to fill a container or packaging to a determined capacity based on weight. Filling scales typically offer a feature that uses a relay switch to shut off a filling apparatus when the target weight is reached. This is especially useful in manufacturing and packaging processes.

Filtering is software averaging in the indicator that smooths out a jumpy weight reading. More filtering gives a steadier display where there is vibration or air movement, but the scale takes longer to settle. Filtering does not make a scale more accurate.

Also known as a platform scale. A floor scale is a large weighing base for higher capacity weighing such as what is typically required in shipping and receiving departments. Floor scales are commonly used to weigh shipping pallets full of material.

Factory Mutual, or FM approved, scales and scale components are approved to operate in hazardous and combustible environments. Corresponds with intrinsically safe equipment.

Scale used for weighing foods. Also known as ingredient scales, portioning scales and restaurant scales. Food scales are commonly stainless steel and feature higher washdown ratings for easier cleaning.

Formulation is a weighing application that uses pre-determined weights for individual ingredients to accurately produce a final product. Many scale manufacturers offer scale hardware and software to accommodate formulation weighing.

GLP stands for Good Laboratory Practices. As it relates to scales, GLP typically refers to data management and export such as with printing weighing results and assigning unique IDs.

GMP stands for Good Manufacturing Practices. As it relates to scales, GMP typically refers to the documentation around the instrument, such as calibration records and traceable printouts of weighing results.

A grain is a unit of mass equal to 1/7000 of a pound, or about 64.8 milligrams. Grains are commonly used for ammunition, pharmaceuticals and precious metals.

Gross weight is the total weight on the scale, including both the product and the container.

Handbook 133 is a NIST publication covering how the net contents of packages are checked. Handbook 44 covers the weighing device itself, while Handbook 133 covers what ends up in the package.

Handbook 44 is a NIST (National Institute of Standards and Technology) publication that provides "specifications, tolerances, and other technical requirements for weighing and measuring devices." Learn more about NIST Handbook 44.

A hanging scale suspends the load beneath it instead of supporting it on a platform. Hanging scales range from small spring dial scales to heavy capacity crane scales used with an overhead hoist.

A hermetically sealed load cell is closed with welded seams and a sealed cable entry rather than a gasket or a potting compound. This is what allows a load cell to survive washdown, outdoor and other wet environments.

The home run cable is the cable running from the junction box back to the indicator. Because it carries the combined signal from every load cell, a fault in the home run cable affects the whole scale rather than one corner.

Hopper scales are containers with loadcells integrated into them for weighing dry bulk materials. Usually dry bulk material is fed into the hopper, weighed, and then emptied into a mixer or package. Hopper scales are commonly used in industrial and agricultural applications where bulk materials are mixed, packaged and sold.

A housing refers to the cover, or enclosure, that houses a scale or indicator's internal and electronic components.

Hysteresis is when the displayed value of a known weight is different depending on the direction of loading. An example of this would be if a 5 lb weight is placed on a scale and the scale displays 5.00 lbs but when the weight is removed from the scale it displays 0.01 lbs instead of returning all the way to 0.00 lbs.

Also known as a weight display or controller. An indicator is a device that typically controls a weighing scale or balance and also displays the menu and weighing results. Indicators are commonly used in industrial applications where a scale base doesn't have the weight display integrated into the same housing.

A very broad term for scales that are typically used in industrial and/or manufacturing applications.

An in-motion checkweigher weighs product while it is moving along a conveyor instead of requiring an operator to set it down on a pan. These are used on production lines where stopping to weigh each package would slow throughput.

Also known as communication interface. An interface is one or a group of input or output ports that allow a scale or balance to connect to an external device through the use of RS-232, USB, Ethernet or other connection methods.

Internal calibration is a feature some scales have that allows calibration of the scale using a built-in mass standard. A physical weight and motorized mechanism built into the scale allows the user to calibrate the scale through menu prompts. Some brands and models also offer automatic internal calibration in which the scale performs its own calibrations based on preset parameters including time, temperature and environmental changes.

Internal resolution is how finely the scale measures behind the scenes, before it rounds the number off for the display. A scale might work internally in steps of 0.001 lb but only show 0.01 lb. Technicians use the internal figure when calibrating.

Intrinsically safe equipment is defined as "equipment and wiring which is incapable of releasing sufficient electrical or thermal energy under normal or abnormal conditions to cause ignition of a specific hazardous atmospheric mixture in its most easily ignited concentration." Intrinsically safe scales, balances and indicators are typically used in environments where there are combustible fumes or materials. An example of this could be paint and chemical manufacturers.

Usually a molded plastic cover that sets over top of a scale or balance display and keypad to protect it from debris, spills and splashes. An in-use cover helps to prolong the life of a scale or balance.

IP, or Ingress Protection, ratings are defined in international standard EN 60529. They are used to define levels of sealing effectiveness of electrical enclosures against intrusion from foreign bodies (tools, dirt etc) and moisture.

IR stands for infrared. An infrared sensor is typically found on analytical balances and can detect hand movements. Tasks such as tare, zero and print can be performed hands-free with a simple wave of a hand.

ISO is an acronym for the International Organization for Standardization. ISO is an international standard-setting body composed of representatives from various national standards organizations including standards for weighing metrology such as calibration methods, practices and procedures. Learn more about ISO.

A scale commonly used in jewelry establishments that can weigh in carats and other measurement units commonly associated with the jewelry industry.

A junction box is the enclosure where the cables from several load cells are wired together and combined into one cable running to the indicator. On a multi-cell scale it is the first place to check when readings go wrong.

The kilogram is the base unit of mass in the SI system, the international metric system used worldwide for scientific and legal measurement. One kilogram is about 2.20462 pounds.

A very broad term for balances that are used in laboratories or research applications.

In general, any person or business that buys, sells, or charges based upon weight within the United States must use a Legal-for-Trade scale. NTEP approved scales are certified for use in legal-for-trade applications. NTEP stands for National Type Evaluation Program and is a non-profit organization that certifies legal-for-trade scales.

Commonly a mechanical level bubble or an electronic display on a scale or balance that visually verifies to the operator that the scale or balance is level. It is important that a scale is level to ensure accurate weighing results.

Linearity is the ability of a scale or balance to display the correct value throughout the full capacity range of the scale. Linearity is tested by placing known weights on the scale from near zero, mid capacity and full capacity.

Live load is the weight that changes, meaning the product or vehicle being weighed. Deadload is the weight of the structure itself. Load cells have to be sized to handle both together.

A load cell is a type of transducer which turns force into a measurable electrical output. Although there are many varieties of load cells, strain gauge load cells are the most common. Load cells are used in weighing scales and balances to determine weight based on the force exerted by the sample placed on the pan.

Loss-in-weight is a feeding method where the scale weighs the supply hopper and measures how fast its weight is dropping. Gain-in-weight is the opposite, weighing the receiving container as it fills.

Mass is a physical property of a material. The mass gives a material weight when gravity pulls the material toward earth. The units of mass are gram and kilogram. The terms mass and weight are often used interchangeably.

A scale that is not digital. A mechanical scale does not use any electronics and relies on physical components to produce weight results. Mechanical beam scales are a good example. Measurements are taken using a combination of counterweights, rods, levers and springs.

For digital scales and balances, the menu is where an operator makes selections and operates the instrument. An operator can navigate through a menu using keys and prompts to perform specific tasks.

A microbalance is an analytical balance that has a readability of 0.001 mg or better. These are used for extremely precise weighing applications, typically research, and for samples that are typically no heavier than 25 grams.

Minimum weight is a manufacturer's suggested specification for the minimum weight a sample must be for the scale to measure accurately. If the sample is below the manufacturer's recommendation, the results could be inaccurate. In some instances, the sample will not produce a result on the display at all.

Also known as a moisture analyzer, a moisture balance is used to determine the moisture content of a sample at set temperatures. The moisture balance uses a combination of weighing and heating methods to determine moisture content.

No, we're not talking about weighing those weird looking mammals that burrow under the ground. We're talking about molar mass, which is defined as the mass of 6.02 x 10²³ atoms of a given element or compound. Mole weighing allows scientists to determine how many moles are in a given sample based on the sample's molar mass which is entered into the scale.

mV/V stands for millivolts per volt and is the standard way of stating load cell output. It is the signal the cell produces at capacity for each volt of excitation. Common values are 2 mV/V and 3 mV/V.

Net weight is the weight of a product or sample less the container or vessel it is being weighed in. Net weight can also be the "total weight" of a collection of sample weights collected over a duration of time.

NIST is the National Institute of Standards and Technology, the federal laboratory responsible for measurement standards in the United States. NIST publishes Handbook 44 and maintains the mass standards that calibration labs trace their weights back to.

NTEP (National Type Evaluation Program) Committee is responsible for the oversight of NTEP. NTEP evaluates and approves weighing instruments used in legal-for-trade applications. Learn about NTEP.

A form of RS-232 cable or connector used for swapping wires such as RxD or TxD between equipment with matching pinouts.

OIML is the International Organization of Legal Metrology. Most of the world outside the United States follows OIML recommendations for weighing equipment and test weights. OIML weight classes run E1, E2, F1, F2 and M1, from tightest tolerance to loosest.

The ideal temperature for an instrument to operate in. As is true with most electronics, if the environment is too cold or too hot, failure can occur or accuracy can decline. A weighing scale, especially digital scales, should be operated within the defined operating temperature range to ensure accuracy.

Overload rating is the manufacturer's specification for the most weight an instrument can handle before the possibility of internal damage occurs. Exceeding the overload rating can damage the scale and may also have dangerous safety concerns for equipment such as crane scales, truck scales and other potentially dangerous heavy-capacity instruments. It is highly recommended to understand the maximum overload rating of your scale before you use it. Refer to the manufacturer's user manual or data sheet.

A pallet scale is a floor scale sized and shaped for weighing palletized loads. U-shaped and low profile pallet scales let a pallet jack drive the load on without a ramp.

Also known as a platform or platter. A pan is the area of a scale that a sample is placed on to take the measurement.

The action of counting parts using a weighing scale. Refer also to counting scale.

Peak hold is a mode that captures and holds the highest weight seen during a measurement instead of showing the current weight. It is common on crane scales, where the operator cannot watch the display at the moment of the lift.

Percent weighing is the process of using a scale or balance to determine the weight of an item as a percentage of a reference weight. This application is commonly used in commercial baking where ingredients are weighed based on a percentage of the flour weight; also known as Baker's Percentage.

Pipette adjustment is a weighing application used to verify and calibrate pipettes. This is usually performed at a high degree of precision using an analytical balance, typically a semi-micro or above. Some manufacturers provide a kit for pipette adjustment which includes the balance, software and consumables.

Can also be referred to as a floor scale or bench scale. The term platform scale is commonly interchangeable with either of the two aforementioned scale types. "Platform" typically refers to a scale that has a weighing base, or pan, separate from a display, or indicator.

PLU stands for Price Look-Up. It is a memory in a retail or price computing scale that stores a price per unit against a short code, so the operator keys in a number instead of entering a price every time.

A weighing balance that is easy to transport or that can be used in the field.

Also referred to as an ingredient scale or food scale. A portioning scale is used for measuring the weight of food to get the desired size, or portion. They are commonly used for specific health diets and food processing.

The electrical power supplied to an instrument. Manufacturers will list power data in their specifications which may include amps, wattage and voltage. There are also different types of power supplies including AC adapters, disposable batteries and/or rechargeable batteries.

A precision balance is a laboratory balance that has a readability of 0.001 gram or less. Often times, precision balances are referred to as top-loading balances because they do not require a draft shield. Some precision balances, however, do include a draft shield.

A preset tare is a tare value typed in at the keypad or recalled from memory instead of captured by weighing an empty container. For example, a known pallet weight can be deducted from every load without ever weighing an empty pallet.

Price computing scales are also referred to as retail scales. Price computing scales often times feature a PLU (price lookup) memory to quickly recall the price per unit of a particular commodity. A good example of an application where a price computing scale would be used is a farmers market. Produce or vegetables sold by weight are measured on the scale and a price is calculated based on the weight. The consumer pays the displayed total on the scale.

Rated output is the signal a load cell produces at its rated capacity, stated in millivolts per volt of excitation. It is one of the specifications that has to match when a load cell is replaced.

Commonly referred to as division size or resolution.

Repeatability is the capability of a scale to display the same value when a weight is placed on the pan more than once. Repeatability is often expressed as a standard deviation of multiple tests using the same amount of test weight.

Reproducibility is the capability of a scale to perform consistently even when conditions change. An example of this would be that a scale in an outdoor environment displays the same weight value when a known weight is placed on it at 40 degrees F and at 75 degrees F.

Resolution is also commonly referred to as readability or division size. The terms are often times interchanged. As it pertains to digital scales, resolution is the smallest change in mass that corresponds to a change in displayed results. Simply put, resolution is the amount the scale will increment by as weight is added or removed.

A broad term used to define a group of scales used in retail applications. These could include price computing scales, shipping scales and food scales.

RS-232 is a type of serial communication used to transmit data between devices such as computers and printers. RS-232 is also commonly used in a wide variety of weighing equipment. Scales that offer an RS-232 interface can be connected to computers and peripheral devices using an RS-232 cable.

The line that receives data in an RS-232 connection.

Safe overload is the load a load cell can take beyond its rated capacity without permanent damage. Safe overload is usually shown as a percentage. For example, 150% safe overload on a 100lb load cell means it can safely handle up to 150lbs.

Scales Plus is a trusted source for purchasing weighing equipment including digital scales, analytical balances, heavy-capacity scales, scale accessories and more. Scales Plus is often referred to as a leading online scale dealer and a reliable resource for everything weighing. This is just what we've heard. It is not yet included in the dictionary.

A scope of accreditation is the document listing exactly what an accredited laboratory is accredited to do, including which measurements, over which ranges, and to what uncertainty.

A scoreboard is a large remote display that can be read from a distance. They are common for truck scales so a driver sitting in their truck can see the weight reading. They take their data from the indicator's serial output.

Sealing is the physical or electronic protection that prevents undocumented changes to a legal-for-trade device. Traditionally this is a lead and wire seal through a calibration switch, so that adjusting the scale visibly breaks it.

An integrated bracket, typically built into the base or housing, that can be used to secure a scale or balance. This helps to prevent unwarranted relocation or theft of the device.

A semi micro balance is a laboratory balance that has a readability of 0.01 mg. Some dual-range analytical balances are also referred to as semi-micro balances when one range of the capacity has a readability of 0.01 mg.

Sense leads are the extra pair of wires in a six wire load cell cable. They tell the indicator what voltage is actually reaching the cell, so it can correct for whatever was lost along the cable. A four wire cell has no sense leads, so a long cable run can cause a span error.

Sensitivity refers to how well a mechanical scale reacts to a very small sample or when a sample changes by a very small amount. A test load or change in test load equal to 1 division or 2 divisions is normally used when performing a sensitivity test on a mechanical scale.

Sensitivity drift is the effect temperature change has on the performance of a scale. Sensitivity drift specifications are usually provided for instruments with higher readability, such as semi-micro and micro balances.

The process of sending data one bit at a time.

A setpoint is a target weight programmed into an indicator that switches an output when the weight is reached. For example, a checkweigher uses setpoints to tell the over, under or accept lights to turn on. Setpoints are what make the process of filling, batching and checkweighing automatic.

A shift test verifies the ability of a scale to display the same result no matter where the sample is placed on the weighing pan. This is also known as a corner-load test. Scale technicians will perform a shift test to verify that a scale is consistent at all four corners and center of the platform. In a shift test a known weight is weighed in the center of the platform and at the center of each quadrant of the pan or at each corner. Usually the known weight is equal to 1/4 or 1/3 of the scale capacity.

Any scale that is used for shipping, warehousing and logistics purposes. Some shipping scales have special programming for communicating with freight carrier companies such as UPS®, FedEx® and USPS® to calculate shipping rates based on weight provided from the scale. This is typically accomplished through connection to a PC and shipping software.

Span is the difference between the reading at zero and the reading at capacity. Calibrating a scale sets both the zero and the span, which is why a span calibration needs a test weight near full capacity.

The amount of time it takes for a scale or balance to stabilize after a sample is placed on a weighing pan. Stabilizing time is determined from the time the sample is placed on the pan to the time the display shows the final result.

Some digital scales incorporate a stable indicator into the display to show the operator visually when a weighing result is final. The scale will show "stable" when the sample weight has been determined.

A start bit is a pattern/command to start the character or transmission. A stop bit is a pattern/command that ends the character or transmission.

Suggested conditions for storage of scales. Manufacturers typically provide ideal storage conditions for instruments that are not in use. This information is usually found in the user manual and should be followed to help facilitate longer life and sustained accuracy.

A strain gauge is a fine metal foil grid bonded to the load cell's spring element. When the element flexes under load the foil stretches and its electrical resistance changes. Four gauges wired as a Wheatstone bridge turn that change into the weight signal.

A summing box is another name for a junction box, used when the box also has trim potentiometers or resistors for equalizing the output of each load cell.

Similar to hopper scales except tank scales are used for weighing bulk liquid materials. See definition for hopper scale above.

Tare is the subtraction of the weight of a container from the overall measurement of the container and sample being weighed. For example, if you place a box of bolts on a scale and you want the weight of just the bolts, you'll need to remove the weight of the box itself from the result. To do so, you'd "tare" the scale removing just the weight of the box's known value, or through a keypad function taring the scale with just the box on it.

Temperature range has various meanings depending on the application. For a moisture balance, the temperature range would be the heating range the moisture balance can facilitate. As it pertains to most other scales, the temperature range might also be referred to as the operating temperature range, which is the ideal temperature the scale or balance should be used in.

Tolerance is how far a scale is allowed to be off before it counts as out of specification. Acceptance tolerance is the tighter limit a scale has to meet when it is new or just adjusted. Maintenance tolerance is the looser limit for a scale already in service.

A totalizer is a running total held by the indicator, adding each accepted weight to a cumulative figure and counting how many went into it. It is used for shift totals, truckload totals and batch records.

Traceability is an unbroken chain of comparisons linking a measurement back to a national standard. A test weight is traceable when its certificate names the higher level standard it was compared against, on up to NIST.

A transducer is any device that converts one form of energy into another. A load cell is a force transducer, converting the force of a load into an electrical signal.

Trimming is adjusting the individual load cell signals in a junction box so that the same test weight reads the same over every cell. It is how a failed shift test gets corrected on a multi-cell scale.

A truck scale is a heavy-capacity scale used to weigh large trucks such as semis, dump trucks and other heavy load vehicles. Truck scales are available in a variety of sizes, styles and capacities. They are also sometimes referred to as heavy capacity vehicle scales.

The line that sends data in an RS-232 connection.

Uncertainty is a figure stating how much a measurement could reasonably differ from the true value. An accredited calibration certificate reports the measured error and its uncertainty together. Tolerance is how far the scale may be off, while uncertainty is how well the calibration itself is known.

Opposite of overload. Underload is used to describe a situation where a sample does not weigh enough for a particular scale's minimum weight recommendation. An underload is outside the minimum range of the scale which can result in inaccurate results or no results at all.

USB stands for Universal Serial Bus, a standard connection for sending data and power between devices. It is one of the most common ways to connect a scale to a PC or other device.

In the pharmaceutical industry, the United States Pharmacopoeia’s (USP) set of standards for managing balances is widely recognized around the world. Minimum weight is the minimum sample quantity required to perform an accurate quantitative analysis where the measurement error of the balance used is taken into account.

Verification is a term used to describe the process of verifying a scale is working properly. This usually goes hand-in-hand with calibrating a scale or inspecting a scale for accuracy. Verification involves using certified test weights to check the accuracy of a scale or balance. Also known as a verification process.

Warm-up time is the period after power-up before an instrument reaches a stable temperature to perform at its best. Analytical and micro balances need hours rather than minutes. More accurate and precise instruments typically need longer to warm up than less accurate instruments.

A washdown scale features a high IP rating that protects the scale from dust, dirt and water. Washdown scales are ideal for use in harsh environments that are wet, dirty and generally considered a bad environment for digital scales. Washdown rated scales are designed specifically for these types of environments.

A built-in hook on the underside of a scale or balance used to hang samples to determine a weight. Typically associated with analytical balances and research weighing applications, such as density determination.

Another term for truck scale or heavy capacity vehicle scale. A weighbridge is technically defined as any large capacity weighing scale that is anchored to a concrete platform or foundation.

By definition, weighing is the process of determining how heavy an object is. This is the primary function of weighing scales and balances. They are designed to determine how heavy objects are, some of which are capable of doing so to an extremely high degree of accuracy.

A weighing application is a designated use for a weighing scale. Scale manufacturers will list the weighing applications their hardware and software is capable of performing. Examples of weighing applications are dynamic weighing, percent weighing, filling, parts counting and of course, basic weighing.

Also referred to as a measurement unit or unit of measure. Examples of weighing units are pounds (lbs), grams (g), ounces (oz), kilograms (kg) and pound ounces (lb:oz).

A weigh module is a load cell packaged with the mounting hardware needed to put it under a tank, hopper or other structure. The hardware handles alignment and thermal expansion so that the cell only sees vertical force.

The actual definition of weight is "a body's relative mass or the quantity of matter contained by it, giving rise to a downward force; the heaviness of a person or thing." Simply put, weight is how much something weighs by a given unit of measure. A weight can also be a physical object, such as a test weight or mass standard. For example, a 100 gram weight used to calibrate an analytical balance.

A Wheatstone bridge is the four-arm resistance circuit that nearly every strain gauge load cell is built around. Excitation goes in across one pair of corners and the signal comes out across the other. Strain on the gauges unbalances the bridge in proportion to the load.

The yield point is the load at which a load cell's spring element bends permanently instead of springing back. Past this point the cell will not return to zero and cannot be calibrated back into specification.

Also commonly referred to when taring a scale, however, they aren't exactly the same. You can "zero" a scale using the tare function when negating a container weight, however, zeroing a scale is just setting the display to show zero regardless of what is or isn't on the platform. Zeroing a scale can be thought of as "resetting" the display to zero. Some scales and balances have a built-in feature that ensures the display always returns to zero when the pan is emptied.

Zero balance is the output a load cell produces with no load on it at all, stated as a percentage of its rated output. A permanent shift in zero balance is the clearest sign that a cell has been overloaded.

Zero tracking is an automatic feature that pulls the display back to zero when the reading drifts slightly near zero. It hides small drift, but it can also absorb a slow real change, such as product building up on a conveyor.