# Glossary

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T   U  V  W  X  Y  Z

## C

 Calibration The calibration tells us to what extent the measured value displayed by a measuring device or measuring instrument is in agreement with the corresponding correct value of the measured quantity. The "correct" value is represented by a reference standard which, in turn, is related to a national standard and thus to the appropriate SI unit.

## D

 Data bus The data bus indicates a system of outputs in which data are transported between processor and other components (memory).

## E

 Electronically commutated In electronically commutated DC motors, the motor windings, which are used to generate a rotating field are switched with no mechanical wear.

## G

 Galvanic separation Galvanic separation functions on the basis of two electronic circuits, e.g., for the power supply to the motor and for the power supply to the control unit, which are completely separate from one another. No direct connection of any kind exists via a conducting material such as iron or copper.

## H

 Holding torque Holding torque is the torque that must be expended to move a gear from the rest position backwards with respect to output. Hysteresis The hysteresis of a pressure gauge is the maximum difference in output values that are obtained at the same pressure between measurements made in the direction of increasing pressure and measurements made in the direction of decreasing pressure. It is measured in a closed measuring cycle between the first and last value in the measuring range and includes both the elastic after-effects as well as effects caused by design, such as friction and backlash.

## L

 LCD (Liquid Crystal Display) The LC displays measured values, etc. It draws very little current and has a flat construction. Lifting force The lifting force is a motive force, which is applied by a linear drive. Lifting speed The lifting speed is the distance covered in unit time (e.g. mm/s) by a linear movement unit (e.g. gear rack). Linearity The linearity (non-uniformity) is the maximum deviation of the characteristic curve from a specified curve after measurements at increasing pressure. In pressure measuring technology, the specified curve is generally a straight line.

## M

 Measuring principle A pressure gauge consists of an elastic measuring element, which becomes deformed under the influence of pressure and which thus clearly represents the pressure variable as an electric signal. The measuring principles can, for example, be inductive, capacitative or piezoelectric. Measuring range The measuring range is the range of values of the quantity measured, pressure. The measured deviations of a measuring device should lie within the given error limits. The limits of the measuring range are the initial and final values.

## O

 Output signal The output signal is an electrical signal that clearly represents the value of the quantity measured, pressure, e.g.: 0 to 10 Volt. It is supplied by the instrument in order to control other instruments or to process the measured value. Operating temperature range (nominal temperature range) The nominal temperature range is the temperature range for which the pressure gauge maintains its specification. Output speed The output speed is the number of revolutions of the output shaft in unit time, e.g. 1/min. Output torque The output torque is equal to the product of the radius of the output shaft and the force acting tangentially (at right angles) to this radius.

## P

 Performance The performance is the work performed in unit time, measured in Nm/s (work = force x distance).

## R

 Regulating range The regulating range is the range in which the drive can be operated without impairing its function (number of revolutions with rotary drives, lift with linear drives). Regulating time The regulating time is the time required by the output shaft to cover a specified displacement e.g. 90∞ in 10 sec.

## T

 Traversing range The traversing range is the maximum distance with a fixed initial and final point, e.g. 80 revolutions.