Glossary

This helpful list contains terminology used frequently in the weighing industry, along with easy-to-understand explanations. New information is updated regularly, so make sure to visit often.

A

Accuracy

The degree to which sample weight conforms to a standard (calibration mass). Accuracy is the ability to display a value that matches the ideal value for a known weight. It is a function of repeatability, linearity and off‐center loading. See also: Resolution, Increment, Readability

Animal Weighing

Some balances and scales feature a mode to allow accurate measurement of living animals that might move during weighing. The scale works out an average weight based on the force exerted by the animal over an extended period of time. Once the internal calculation is completed by the balance, it will hold the value. See dynamic weighing.

B

Backlit Display

The liquid crystal display (LCD) of some balances features a backlight to improve visibility of weighing results.

Balance

A weighing machine. The terms "scale" and "balance" are often incorrectly used interchangeably. A balance determines mass by balancing an unknown mass against a known mass, as with a two-pan assay balance. Modern balances usually are designed with a force restoration mechanism, which creates a force to balance the force due to the unknown mass. See scale. See also: Scale

Battery Powered

The balance or scale are said to be battery powered when the units are operated using batteries. The battery powered units are portable and hence are often suitable for field applications.

Baud Rate

The speed of communication when using the RS-232 interface. The greater the number the faster the data is sent between 2 devices. Usually balances use 300 to 9600 baud.

Below balance weighing

To determine the specific gravity of a sample, below balance weighing is needed. The sample is tied to a wire attached to the under-hook of a balance and immersed into the liquid to know the weight of the sample in that liquid.

C

Calibration

A procedure that enables the balance or scale to be reset to a known standard mass.

Capacity

The maximum weight that can be placed on the scale or balance.

Checkweighing

A function that compares the current weight to a predetermined setting and indicates if the load is below, above, or within an acceptable range.

D

Date

Balances can be programmed to display and print the date on which weighing operations were performed.

Density Determination

Density is a measure of mass per unit volume. A balance is used to determine the density of solid or liquid materials. Density of a solid material is found by weighing it in air, and then suspending it in liquid and weighing it again. To determine the density of a liquid, a special float of known volume is weighed in air and then in the liquid. Density can be determined manually or automatically calculated by software in some balances.

E

Eccentric Loading

See Off-centre loading. See also: Off-centre Loading

External Calibration

The calibration process of a balance using a known external weight (often referred to as "suggested calibration weight").

F

Force Restoration

A method to determine an unknown mass by balancing the force produced by the mass with a system-created force using coils mounted in a magnetic field. Also called "servomotor" or "force motor."

G

GLP

Good Laboratory Practice (GLP) generally refers to a system of management controls for laboratories and research organisations to ensure the consistency and reliability of results. Laboratory balances can provide GLP printouts with traceability, which include date, time, balance identification number, etc.

I

Increment

See Divisions. See also: Accuracy, Readability, Resolution

Ingress Protection (IP) Rating

The IP rating classifies the degree of protection against the intrusion of solid objects such as dust and water. It provides specific information about a scale's washdown ability, or if it can be used in a wet or dusty environment.

Internal Calibration

An automatic calibration process that uses a weight available inside the balance. Calibration can be programmed by the user to occur when the temperature changes, at regular intervals, or when needed.

Internal Rechargeable Battery

Digital balances are often powered by an internal battery that is recharged when connected to the main power supply.

L

Levelling

This procedure uses adjustable feet and a levelling bubble to ensure the balance's platform is horizontal. Levelling helps the balance adapt to uneven or sloped surfaces, ensuring repeatable and accurate results if the balance is moved.

Linearity

The ability of a scale or balance to show the correct value throughout the weighing range. Linearity can be tested by placing known weights on the balance from near zero to full capacity.

Load Cell

See Strain Gauge Load Cell. See also: Strain Gauge Load Cell

M

Mass

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

A set of procedures that can be followed to change the characteristics of a balance. The menu consists of a number of options (parameters) that are set at the factory or can be specified by the user.

Multiple Weighing Units

More than one weighing unit. See Weighing units. See also: Weighing Units

O

Off-centre Loading

The ability to display the same value when a weight is placed anywhere on the weighing platform. Tested by weighing in the centre of four quadrants on the platform. Also called "eccentric loading" or "shift test."

P

Parameter

A set of procedures that can be followed to change the characteristics of a balance. The menu is made up of a number of options, called parameters, that can be set at the factory or in some cases by the user. See also: Menu

Parts Counting

A weighing application that uses an average piece weight (representative sample) to determine the number of items having the same mass by placing them on the platform. Piece weight is entered by the user or determined by measuring a sample on the scale.

Percent Weighing

Using a balance to determine the weight of an item as a percentage of a reference weight.

R

Readability

How well a scale displays the correct results. Readability is the value of the finest division of the scale. See accuracy, increment and resolution. See also: Accuracy, Increment, Resolution

Repeatability

The degree of agreement between repeated measurements of the same mass on the same balance, under the same conditions.

Reproducibility

See Repeatability. See also: Repeatability

Resolution

The total number of scale divisions available in that device. See Accuracy, Increment and Readability. See also: Accuracy, Increment, Readability

RS-232

A method of transmitting data via wires, allowing balances to communicate with printers or computers. Scales and balances with data communication capabilities use RS-232 interfaces to connect to peripheral devices.

S

Scale

A weighing machine. The terms "scale" and "balance" are often incorrectly used interchangeably. Historically, a scale was a device that displayed weight by measuring a deflection, such as a spring scale. Modern scales generally use springs. Weighing devices with strain gauge load cells are sometimes referred to as scales. See Balance. See also: Balance

Security Bracket

A built-in bracket that attaches the balance to a lock and cable to help prevent theft or relocation of the device.

Shift Test

See Off-centre loading and Eccentric loading. See also: Off-centre Loading

Specific Gravity

Specific gravity is a dimensionless quantity. It is the ratio of density of a substance to the density of reference substance ( water, air, alcohol, etc.). See Density Determination. See also: Density Determination

Stability

The point at which results do not change after a weight has been added to the platform.

Stable Indicator

A feature or symbol that appears on the display indicating that the balance has provided results and the displayed value no longer will change.

Strain Gauge Load Cells

A method to determine mass using a mechanical component that is deflected by the addition of an unknown mass. The amount of deflection is measured by resistive elements (strain gauges) mounted on the mechanical component.

T

Tare

Tare means setting a display to show zero weight. This is used to remove the weight of any packing or containers, leaving only the weight of the material on the display. The tare value is subtracted from the remaining weight added to a scale. For example, if 200g is tared on a scale with a capacity of 500g, a capacity of 300g remains. "Tare" and "zero" are frequently used interchangeably.

Temperature Compensation

The ability to correct errors in the weighing system due to temperature changes, generally achieved via software or electronics on precision balances.

Time

Balances can be programmed to display and print the time at which weighing operations were performed.

Totalisation

The ability of a balance to add together multiple results when weighing separate items.

W

Weighing

To find the weight (mass) of an unknown against a standard known mass.

Weighing Unit

Unit measure displayed on a balance that provides the weight of an unknown mass, such as grams, kilograms, milligrams, pounds, ounces, carats, grains, Newtons, etc.

Weight

The weight of an object is the result of gravity pulling a mass toward the Earth. When a balance is calibrated using a known mass, any unknown mass placed on the scale will have a weight proportional to the known mass. A weight can also be any mass that is placed on the scale.

Z

Zero

This sets the display to show zero weight. Used to reset the zero condition of a scale when small amounts of material are on the platform. Zero does not take away from the capacity of a scale; however, it works only in a very small range around the original zero condition for the scale. Zero and tare sometimes are located on the same key, as the terms often are used interchangeably.