Glossary Of Terms
Bidirectional: Data flow in either direction on a wire between pieces of equipment. Each equipment item can both receive and transmit data. Load receiver (platform) can receive loads in both directions.
Calibration: A scale or weighing system adjusted to meet performance and accuracy specifications. The comparison of load cell outputs against standard test loads.
Capacity: The maximum weight limit of a scale. The scale’s capacity should be at least 20% higher than the average maximum weight of the products weighed on the scale. Otherwise you will greatly shorten the lifespan of the scale, and accuracy may be affected. For example, if you are weighing 10 kg bags of potatoes, the capacity for your scale should be at least 12 kg.
Character: One letter, number, or symbol, printed or displayed. A space is considered a character.
Checkweigher: A scale used to verify predetermined weight within prescribed limits/ranges.
Class: A scale’s class is based on the range of the readability.
Class II: A scale with a readability between 1 mg (0.001 g) and 50 mg (0.05 g)
Division (d): A scale's smallest graduated interval of display and output data. Also called graduation, grad or interval.
Electrical Noise: Extraneous undesirable currents or voltages which interfere with desirable electrical quantities. Some causes are distant lightning, radio transmitters, welding equipment, electrical switching equipment, poor brush contact on motors, and other electronic devices utilizing switching power supplies.
Electrostatic Charge: An electric charge on the surface of an insulated object.
Electrostatic Discharge (ESD): A rapid discharge of an electrostatic potential that can cause damage to integrated circuits.
EMI (Electromagnetic Interference): Electromagnetic interference (EMI) is a disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction. Also called radio-frequency interference (RFI) when in the radio frequency spectrum.
Ethernet: A system for connecting a number of computer systems to form a local area network, with protocols to control the passing of information and to avoid simultaneous transmission by two or more systems.
Graduation: A defining line or one of the lines defining the subdivisions of a graduated series. The term includes such special forms as raised or indented or scored reference “lines” and special characters such as dots. (See division.)
Indicator: The weight indicating element of an electronic scale. An instrument converts weight data from the load receiver into information that can be displayed, output and stored. An instrument’s panel contains controls required for normal operation, as well as weight readout.
Indicator Capacity: The largest weight that the weight indicating device is capable of reading. In a dial or beam, the capacity is limited, in an electronic instrument, the capacity is limited by the display capabilities and the resolution.
Interface: A device or circuit that allows two units to communicate. Some of the standard interfaces used in the scale industry are 20 mA current loop, BCD, RS232, RS422 and RS485.
Interval: (See division.)
Legal For Trade (LFT): In the weighing industry, legal for trade refers to devices that have met national standards for use in commercial applications that involve the sale, purchase or exchange of goods based on measurement (weight). Legal use of commercial weighing equipment in Canada is governed by Measurement Canada. In order to be used as a basis for financial transactions in the U.S., weighing equipment must meet legal for trade requirements governed by the National Conference on Weights and Measures’ NTEP Certificate of Conformance program. Most other countries globally (outside of the U.S. and Canada) have adopted International Organization of Legal Metrology (OIML) requirements for weighing equipment.
Measurement Canada (MC): The Canadian governmental agency responsible for ensuring accuracy in the selling of measured goods, developing and enforcing the laws related to measurement accuracy, approving and inspecting measuring devices and investigating complaints of suspected inaccurate measurement.
NTEP (National Type Evaluation Program): NTEP provides a one-stop evaluation process that satisfies the initial requirements for introduction of weighing and measuring devices in the U.S.
Output: A serial, analog, ethernet, current, voltage or other means to signal or provide data in any one of several communication mediums. The signal produced by a load cell.
Pan: The flat level deck or surface of a scale on which product or material is positioned for weighing.
Platform: The flat level deck or surface of a load receiver on which the load is positioned for weighing.
Port: A point at which signals may be introduced to or extracted from a circuit, device, or system.
Repeatability: This is the scale’s ability to show consistent results under the same conditions (same device, same operator, same environment). To determine a scale’s repeatability, a test weight is placed on the scale then removed several times while recording each weight result. The repeatability measures how spread out the values are around the mean or average value.
Resolution: Resolution is the smallest increment in applied weight that can be detected or displayed on a scale. In all scales, this quantity is most affected by the number of digits that are displayed when an object is weighed.
RFI (Radio Frequency Interference): Radio frequency energy of sufficient magnitude to possibly affect operation of other electrical equipment.
RS232 (EIA-232): RS232 is an electrical signaling specification published by the Electronic Industries Alliance (EIA). Two connector types, the 25-pin (DB25) connector, or 9-pin (DB9) with specific pin assignments, are accepted as standard RS232 or serial connectors. RS232 is a common physical interface standard for interconnection of devices, such as a scale instrument and printer, or scale instrument and computer. The standard allows for a single device to be connected at baud rates up 115,000. The faster the baud rate, the shorter the distance.
RS422: Data transmission, using balanced or differential signaling, with unidirectional, terminated or non-terminated transmission lines, point to point, or multi-drop. In contrast to RS485 (which is multi-point instead of multi-drop) RS422 does not allow multiple drivers but only multiple receivers.
RS485 (EIA-485): A serial communication protocol similar to RS232 that can achieve longer transmission distances. The notable difference, RS485 features a floating ground on the signal line.
Safety Factor: A figure denoting the overload (and allowance thereof) a device can withstand before it physically breaks down and fails.
Scale: A device for weighing, comparing and determining weight or mass. The combination of a load receiver and an instrument; a complete weighing device.
Ticket: A single or multiple copy sheet or form on which data items pertaining to a weighing transaction will be printed in one or more operations.
Tolerance: A value that fixes the limit of allowable error or departure from true performance or value. Usually expressed as the number of divisions.
Zero Balance: Zero balance occurs when an electronic instrument indicates zero with no load applied, or when the beam/dial on a mechanical scale has been adjusted to zero, with no load applied.