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MF

calibration services

J Purpose of calibration

J overview measured values

J scope of accreditation

DB_Calibration_services 01/2015

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The purpose of calibration

Correct and reliable measurements are prerequisites for all

high-quality industrial production. Among other things,

measuring and testing equipment is used for quantitatively

determining properties, as well as for controlling, regulating

and automating processes used in manufacturing. Measure-

ments are therefore an important element of industrial quality

assurance, as can be seen in DIN EN ISO 9000 and 9001.

All equipment used for measurements, including equipment for

auxiliary measurements, e. g. of environmental conditions, and

which have a significant influence on the accuracy and validity

of the result of the test or sampling, must be calibrated prior

to use.

To ensure the accuracy of measurement results, the

measuring instruments, test equipment and standards

must be referred back to SI units. All standards are

almost the same – but not quite. This is because the

different standards within the calibration hierarchy

are regularly compared to a fixed hierarchical

structure.

Measuring devices must be calibrated. In other words,

the deviation of the device reading from the correct

value of the measured quantity must be known.

PTBNationalStandard

Accredited DAkkS laboratory

ReferenceDAkkS certificate

Internalworks laboratory

Company standardsWorks certificates / Test certificates

Calibrator

Test equipment of the company

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At the very bottom of the hierarchy are the many different pieces

of test equipment within a company. In terms of temperature

measurement technology, these include desktop or hand-held

instruments, for example. Manual measuring instruments and

digital or analogue manometers are frequently used in pressure

measuring technology.

Since this test equipment wears, ages or drifts as a result of

constant use, it must be regularly connected to a company

standard. In the case of temperature or pressure measurement,

this standard is a temperature or pressure calibrator, which is

very often kept in protective storage in the company laboratory

and used solely for calibration purposes.

These calibrators are in turn regularly connected and tested

with standardsof the next higher hierarchy level, such as a

reference standard of a DAkkS laboratory.

At the very end of this closed chain is the national standard.

In Germany, the Physikalisch-Technische Bundesanstalt

(PTB) is responsible for realising and disseminating SI units.

It collaborates closely with the national metrology institutes

(NMI) in other countries to ensure the international equivalence

of measurement findings.

The following questions frequently arise: Are we actually using

the same dimensions? And do our instruments all operate

in the same way? So it is not surprising that reference to the

national standards is increasingly becoming the „norm“.

The decision as to which stage in the calibration hierarchy one

should „enter“ at is largely determined by the required level of

measurement accuracy. The following rule of thumb applies:

The further down the hierarchy, the more stages of comparison

between the standards have already been completed. The

standard is less accurate - but calibration is usually cheaper

and faster because it is less complicated.

A national standard embodies the most accurate

realisation of the unit of the International System of

Units (SI) available in a country.

With a DAkkS-certified temperature or pressure

calibrator, the customer receives a very precise

company standard. This company standard allows

works test certificates to be created for existing test

equipment very cost effectively. Traceability to national standards

is thus ensured.

Dr. Siebert & Kühn GmbH & Co. KG * Struthweg 7-9 * D-34260 Kaufungen * Telefon: 0 56 05/ 8 03 - 0 * Fax: 0 56 05/ 803 - 54/ 60

Dr. Siebert & Kühn GmbH & Co. KG Struthweg 7-9 34260 Kaufungen Germany

akkreditiert durch die / accredited by the

Deutsche Akkreditierungsstelle GmbH

als Kalibrierlaboratorium im / as calibration laboratory in the

Deutschen Kalibrierdienst 000271

Kalibrierschein Kalibrierzeichen

D-K- 19636-01-00

Calibration certificate Calibration mark 2014-11

Gegenstand Object

Mikrokalibrierbad Micro calibration bath

Hersteller Manufacturer

Dr. Siebert & Kühn GmbH & Co. KG 34260 Kaufungen

Typ Type

TP3M165E

Fabrikat/Serien-Nr. Serial number

1411861

Auftraggeber Customer

Mustermann AG Mustergass 1 12345 Musterstadt

Auftragsnummer Order No.

100 741 854

Anzahl der Seiten des Kalibrierscheines Number of pages of the certificate

4

Datum der Kalibrierung Date of calibration

2014-11-30

Dieser Kalibrierschein dokumentiert die Rück-führung auf nationale Normale zur Darstellung der Einheiten in Übereinstimmung mit dem Internationalen Einheitensystem (SI). Die DAkkS ist Unterzeichner der multilateralen Übereinkommen der European co-operation for Accreditation (EA) und der International Labora-tory Accreditation Cooperation (ILAC) zur ge-genseitigen Anerkennung der Kalibrierscheine. Für die Einhaltung einer angemessenen Frist zur Wiederholung der Kalibrierung ist der Benutzer verantwortlich. This calibration certificate documents the traceability to national standards, which realize the units of measurement according to the International System of Units (SI). The DAkkS is signatory to the multilateral agreements of the European co-operation for Accreditation (EA) and of the International Laboratory Accreditation Cooperation (ILAC) for the mutual recognition of calibration certifica-tes. The user is obliged to have the object recali-brated at appropriate intervals.

Dieser Kalibrierschein darf nur vollständig und unverändert weiterverbreitet werden. Auszüge oder Änderungen bedürfen der Genehmigung sowohl der Deutschen Akkreditierungsstelle GmbH als auch des ausstellenden Kalibrierlaboratoriums. Kalibrierscheine ohne Unterschrift haben keine Gültigkeit. This calibration certificate may not be reproduced other than in full except with the permission of both the Deutsche Akkreditierungsstelle GmbH and the issuing laboratory. Calibration certificates without signature are not valid.

Datum Date 2014-11-30

Stellv. Leiter des Kalibrierlaboratoriums Assistant Head of the calibration laboratory

Olaf Schilling

Bearbeiter Person in charge Olaf Schilling

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Temperature LaboratoryThe temperature laboratory is accredited for temperatures

from -30 °C to 1300 °C. Thermocouples, indicating temperature

measuring and test instruments, as well as temperature block

calibrators can be calibrated within this measuring range.

Resistance thermometers can be calibrated between -30 °C

and 960 °C. The basis of each calibration is the international

temperature scale of “ITS-90”. Measurements are executed

in accordance with DAkkS calibration guidelines of the

German national metrology institute (PTB) for temperatures

close to defined fixed points. This ensures the best possible

determination of the temperature characteristic curve. If

desired, other temperature values (e.g. from real operational

areas) can be included in the calibration.

Calibration services

For Pressure, Temperature and Electrical ValuesThe creation of a calibration service according “DAkkS Deutscher

Kalibrierdienst” for temperature, pressure and electrical

measured values firmly continues and underlines the long

tradition and more than 100 years of experience which SIKA has

in this sector. SIKA temperature and pressure sensors, as well

as measure, test and calibration instruments are available with

either a works test certificate or DAkkS calibration certificate.

This guarantees the traceability of measured values to approved

(national) standards as specified by DIN EN ISO 9000 ff in

numerous areas. Our DAkkS laboratory is your competent

contact for recalibration. Our services also include calibration

to DAkkS guidelines or calibration on the basis of works test

certificates for external products.

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Pressure LaboratoryThe calibration laboratory for “absolute pressure and positive

overpressure” allows the calibration of analogue and digital

pressure measuring devices and pressure sensors with an

electrical output signal (e. g. 0...10 V, 4...20 mA, ...). Calibration

is carried out as a comparison measurement against a dead

weight tester utilised as the DAkkS reference standard. The

dead weight tester is used to pressurise the instrument under

test with a defined pressure from 1...1200 bar. Depending on

the actual measuring range, the smallest possible measuring

uncertainties are 0.7 mbar.

Laboratory for Electric ValuesResistors and ohmmeters can be calibrated from 0 to 2 kΩ.

Depending on the resistance value, the smallest possible

measuring uncertainty is 0.1 mΩ. DC voltmeters and

transmitters can be calibrated between 0 and 20 VDC with a

smallest possible measuring uncertainty of 2 μV. DC testing

and measuring devices for standard signals (0)4...20 mA can

be calibrated with a smallest possible measuring uncertainty

of 0.05 μA.

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Scope of accreditation

* The smallest assignable measurement uncertainties are specified by DAkkS-DKD-3 (EA-4/02). These are expanded measurement uncertainties with a coverage probability of 95 % and, unless stated otherwise, have the multiplying factor k = 2. Uncertainties for which no unit of measurement is given are relative values in relation to the measuring value unless otherwise specified.

Measured value Measuring range Uncertainty of measurement

PressureAbsolute pressure Pabs 1 bar DIN EN 837:1997 / DAkkS-DKD-R 6-1:2010

EURAMET cg-17 / version 2.0principle of measurement pabs = pe + pamb

2...61 bar

> 61...1201 bar

Positive overpressure pe 0 bar DIN EN 837:1997 / DAkkS-DKD-R 6-1:2010EURAMET cg-17 / version 2.01...60 bar

> 60...1200 bar

Temperature

Resistance thermometers and direct indicating thermometer

0.00 °C Icepoint

-30...0 °C Oil bath with Al-Block

> 0...100 °C

> 100...300 °C Silicon oil bath with Al-Block

> 300...550 °C Salt bath

> 550...660 °C Tube furnace withNa-Heat pipe> 660...960 °C

Noble metal thermocouples -30...550 °C Oil bath with Al-Block

> 550...1000 °C Tube furnace with Na-Heat pipe

> 1000...1300 °C Tube furnace

Base metal thermocouples -30...200 °C Thermostatted bath

> 200...550 °C

> 550...1000 °C Tube furnace with Na-Heat pipe

> 1000...1300 °C Tube furnace

Temperature block calibrators -55...-35 °C DAkkS-DKD-R 5-4:2010

> -35...133 °C

> 133...660 °C

> 660...1000 °C

> 1000...1300 °C

Electrical Values

Indicators and simulators for thermocouples

-200...1750 °C Noble metal thermocouples / DAkkS-DKD-R 5-5:2010

-200...1750 °C Base metal thermocouples / DAkkS-DKD-R 5-5:2010

Indicators and simulators for resistance thermometer

-200...850 °C Direct resistance measuring / DAkkS-DKD-R 5-5:2010

-200...850 °C Calibration with resistance simulator / DAkkS-DKD-R 5-5:2010

Voltage (DC) 0.0...0.1 V

> 0.1...0.2 V

> 0.2...20 V

Current (DC) 0...2 mA

> 2...20 mA

Electrical resistance 0...2 kΩ Measuring with digital multimeter

0 ...25 Ω AC measuring, 75 Hz

> 25...100 Ω

> 100...400 Ω

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Measured value Measuring range Uncertainty of measurement Minimum measurement uncertainty * Remarks

PressureAbsolute pressure Pabs 0.1 mbar + 6.5 x 10-5 x pabs Pressure medium: Oil

The expected uncertainty of measurement of the used barometer is to be considered. Atmospheric air pressure pamb1.5 mbar + 7.0 x 10-5 x pabs

Positive overpressure pe 0.1 mbar + 6.5 x 10-5 x pe Pressure medium: Oil

1.5 mbar + 7.0 x 10-5 x pe

Temperature

Resistance thermometers and direct indicating thermometer

10 mK Calibration on fixed-point of temperatur

30 mK In comparison with resistance thermometer in thermostatted baths

15 mK

25 mK

25 mK

0.1 K In comparison with resistance thermometer

0.8 K

Noble metal thermocouples 0.5 K In comparison with thermocouples

1.2 K

1.8 K

Base metal thermocouples 0.2 K In comparison with resistance thermometer and thermocouples

1.0 K

1.5 K

2.5 K

Temperature block calibrators 0.3 K In comparison with resistance thermometer and thermocouplest = Measuring value °C0.2 K

1.5 mk* t / °C

2.5 K

4.5 K

Electrical Values

Indicators and simulators for thermocouples

0.70 K

0.20 K

Indicators and simulators for resistance thermometer

6 x 10-6 x R R =Measuring value

10 mK

Voltage (DC) 2 μV U = Measuring value

4 μV

50 x 10-6 x U

Current (DC) 0.05 μA I = Measuring value

0.1 x 10-3 x I

Electrical resistance 10 x 10-6 x R + 1 mΩ R = Measuring value

0.1 mΩ

5 x 10-6 x R

6 x 10-6 x R