A QR code (abbreviated from Quick Response code) is a specific matrix barcode (or two-dimensional code) that is readable by dedicated QR barcode readers, telephone cameras, and to a less common extent, computers with webcams. The code consists of black modules arranged in a square pattern on a white background. The information encoded may be text, URL, or other data.

We are using QR codes for easy data access using smart phones.

In order to continuously perform correct measurements, utilized measuring and test equipment must be monitored and calibrated on a regular basis. The corresponding time period is known as the calibration interval. Users of measuring and test equipment frequently ask how often calibration of this equipment is required.

There is no single correct answer to this question, because calibration always represents an instantaneous snapshot of actual conditions which is dependent upon a variety of factors including the following:

• Measured quantity and allowable tolerance range
• Level of stress to which the equipment is subjected
• Stability of past calibrations
• Required measuring accuracy
• Quality assurance requirements

In the final analysis, this means that the period of time between any two calibrations must be determined and monitored by the user himself. We recommend a calibration interval of 1 to 3 years. In order to assist our customers in making this often costly decision, we offer free consultation services provided by our own employees. As a rule, we specify a period of 1 year in our factory calibration certificates. Deviations from this rule should be noted by the customer in the purchase order, as well as in the delivery note.

Frequency is defined as a number of cycles per unit time. In physics and engineering disciplines, such as optics, acoustics and radio frequency is usually denoted by a Latin letter f

The period, usually denoted by T, is the length of time taken by one cycle, and is thereciprocal of the frequency f:

Example:

Low frequency (LF) is a rate of oscillation in the range of about 3 Hz to 300 kHz

Radio frequency (RF) is a rate of oscillation in the range of about 300 kHz to 3000 GHz

Radio spectrum:

Analog-to digital conversion.

(1) The closeness of agreement between a test result and the accepted reference value (ISO 5725-1). (2) Closeness of agreement between the result of measurement and a true value of the measurand. Accuracy is a qualitative concept (VIM

The operation of bringing a measuring instrument into a state of performance suitable for its use.

Current which reverses polarity at a uniform frequency.

An instrument that measures the height above ground.

A meter that measures the flow of electrical current in amperes.

The basic unit of electric current adopted under the Systeme International dÕUnites.

The power value obtained in an alternating current circuit by multiplying the effective values of voltage and current. The result is expressed in volt-amperes, and must be multiplied by the power factor to secure the average or true power in watts.

The organization being audited

A unit of measure for data transmission speed. It represents the number of signal elements transmitted per second.

The equation of a straight line, calculated from a set of measurement results, which attempts to minimize the differences between the line and the measurement results. There is more than one statistical method used, each of which may place the straight li

The current amplification factor of a transistor when connected in a common-emitter configuration.

A characteristic curve showing the relation between magnetic induction (B) and magnetizing force (H) for a magnetic material. It shows the manner in which the permeability of a material varies with flux density.

A method of winding transformers in which the wires are placed side by side and wound together.

Two strips of dissimilar metal bonded together so that a change in temperature will be reflected in the bending of the element, as a result of differential expansion.

A unit of heat equal to the amount of heat required to raise one pound of water one degree Fahrenheit at one atmosphere pressure.

Eight related bits of information processed as a unit. Eight bits equals one byte.

Check or adjust the graduations of a quantitative measuring instrument.

One particular measurement in a sequence of measurements aimed at providing calibration.

A set of operations that establish, under specified conditions, the relationship between the values of quantities indicated by measuring instrument or measuring system and the corresponding values realized by standards.

A temperature scale based on mercury in glass thermometer with the freezing point of water defined at 0 degree C and the boiling point of water defined at 100 degree C, both under conditions of normal atmospheric pressure.

Provide evidence for or authorize officially.

A property that helps to differentiate between items of a given population. Note

An instrument for comparing some measurement with a fixed standard.

The transmission of heat or electricity or sound.

Elements used to mechanically make or break an electric circuit.

Supplier in a contractual situation

The value added algebraically to the uncorrected result of a measurement to compensate for systematic error.

Action taken to eliminate the causes of an existing nonconformity defect or other undesirable situation in order to prevent recurrence.

The time required for the trailing edge of a pulse to decrease from 90 percent to 10 percent of its maximum amplitude.

Nonfulfillment of an intended usage requirement of reasonable expectation, including one concerned with safety.

Extent to which evidence is produced to provide confidence that specified requirements are fulfilled.

A voltmeter that operates on the potentiometric principle. The unknown voltage is compared to an adjustable calibrated voltage developed within the differential voltmeter.

A circuit in which the output voltage is proportional to the rate of change of the input voltage.

An electronic voltmeter that gives readings in digits.

A current with a constant polarity.

Action to be taken to deal with an existing nonconforming entity in order to resolve the nonconformity.

Any deviation from the desired waveform.

The alternating current value that will produce the same amount of heat in a resistance as the corresponding direct current value.

The ration of useful output energy, usually expressed as a percentage.

Employs a solenoid to provide mechanical action to move a varying number of electrical contacts back and forth or on and off.

An electric circuit designed to cause a start and stop action or a switching action.

The region surrounding an electric charge in which another charge experiences a force.

Based on actual measurement, observation, or experience without regard to science and theory.

The result of a measurement minus the true value of the measurnand.

The tuning or altering of a control device by the manufacture to bring it into specification.

An instrument for measuring the frequency of an AC signal.

The number of recurrences of a periodic phenomenon.

Function test often duplicates unit test activities sincefunction testers do not assume that unit test is adequately done.

The method of measurement in which the value of a measurand is obtained by measurement of the appropriate base quantities.

The unit of frequency.

The opposition in an electric circuit to the flow of an alternating current.

Electrical devices made of wound or coiled wire.

The process of measuring, examining, testing, gauging, or otherwise comparing the unit with the applicable instruments.

This is inspection whereby either the unit of product is classified as conforming or nonconforming, or the number of nonconformities in the product is counted, with respect to a given requirement or set of requirements.

An undesired change over a period of time, which change is unrelated to input, operating conditions, or load.

Calculation of the value of a function between the values already known.

International Organization for Standardization.

Small, rapid variations in a waveform due to mechanical disturbances.

Perpendicular to the force of gravity.

A system that manages operations of a testing laboratory.

The degree to which performance or response approaches the condition of being linear.

A type of force transducer designed primarily for the measurement of load or weight.

1,000,000 ohms of resistivity.

The act or process of measuring.

A material measure, measuring instrument, reference material, or system intended to define, conserve, or reproduce a unit or one or more values of a quantity in order to transmit them to other measuring instruments by comparison.

The estimated amount by which the measured quantity may depart from the true value.

All of the measuring instruments, measurement standards, reference materials, auxiliary apparatus, and instructions that are necessary to carry out a measurement. This includes measuring equipment used in the course of that used in calibration.

The basic unit of length adopted under the Systeme International dÕUnites (approximately 1.094 yards)

Nonfulfillment of a specified requirement.

Pertaining to a response which is not directly or inversely proportional to a given variable.

A switch in which the contracts are closed without any external force acting upon it.

A switch in which contracts are open when no external forces act upon the switch.

Any method of measurement in which the reading is taken at zero.

A unit of electrical resistance equal to the resistance between two points on a conductor when a potential difference of one volt between them produces a current of one ampere.

A instrument for measuring resistance.

Company, corporation, firm, enterprise, or institution or part, thereof, whether incorporated or not, public or private, that has its own functions and administration.

Responsibilities, authorities, and relationships, arranges in a pattern, through which an organization performs its functions.

Having waveforms that are of the same frequency but not passing through corresponding values at the same instants.

The apparent displacement of an object as seen from two different points that is not on a line with the object.

The amount of voltage or change between a point and a zero reference point.

The difference in potential between any two points in a circuit.

The closeness of agreement between randomly selected individual measurements or test results.

Process of demonstrating whether an entity is capable of fulfilling specified requirements.

Status given to an entity when capability of fulfilling specified requirements has been demonstrated.

The totality of features and characteristics of a product or service that bears on its ability to satisfy given needs.

All those planned or systematic action necessary to provide adequate confidence that adequate or service will satisfy given needs.

A systematic and independent examination to determine whether quality activities and related results comply with planned arrangements and whether these arrangements are implemented effectively and are suitable to achieve objectives.

Statement of fact during a quality audit and substantiated by objective audience.

The operational techniques and the activities that sustain a quality of product or service that will satisfy given needs; also, the use of such techniques and activities.

Systematic examination of the extent to which an entity is capable of fulfilling specified requirements.

The totality of functions involved in the determination and achievement of quality.

Document stating the quality policy and describing the quality system of an organization. See Davis Calibration Quality Manual.

Document setting out the specific quality practices, resources, and sequence of activities relevant to a particular product, project, or contract.

Overall intentions and direction of an organization with regard to quality, as formally expressed by top management.

Those costs incurred in ensuring satisfactory quality, as well as the losses incurred when satisfactory quality is not achieved.

Continued monitoring and verification of the status of an entity and analysis of records to ensure that specification requirements are being fulfilled.

Organizational structure procedures, processes and resources needed to implement quality management.

Expression of the needs or their translation into a set of quantitatively or qualitatively stated requirements for the characteristics of an entity to enable its realization and examination.

(1) Extent of coverage of effectiveness. (2) Measure of distance.

(1) Something graduated when used as a measure or rule. A series of spaces marked by lines to indicate the magnitude of some quantity. (2) A weighing device.

Full scale output divided by the rated capacity of a given transducer / load cell.

Element of measuring instrument or measuring chain that is directly or indirectly affected by the measurand.

Modules of the difference between the two limits of a normal range.

The range of values or numerical value which ties the performance of the product parameter.

(1) The entire range of wavelengths within which electromagnetic radiations occur. (2) A segment of wavelengths which has a special function or possesses special properties.

The ability of a measuring instrument to maintain constant metrological characteristics with time.

(1) Conforming to or constituting a standard of measurement or value. (2) a basis for comparison. (3) the ideal in terms of which something can be judged.

A mathematical quantity used to characterize the dispersion of results.

Uncertainty of the result of a measurement expressed as a standard deviation.

The device being compared with the calibration standard.

The pass or fail limit.

A semiconductor device made of materials whose resistance varies as a function of temperature.

Measurement of duration.

Cause of rotary motion. It is equal to the applied force multiplied by the distance from the center of rotation.

Management approach of an organization, centered on quality based on the participation of its member and aiming at long-term success through customer satisfaction and benefits of all members of the organization and to society.

Ability to trace the history, application, or location of an entity by means of recorded identification.

A parameter, associated with the result of a measurement that characterizes the dispersion of the values that could reasonably be attributed to the measured.

A value, quantity, or magnitude of which other values, quantities, or magnitudes are expressed.

Confirmation by examination and provision of objective evidence that specified requirements have been filled.