E+E Calibration laboratory for Humidity
Calibrations carried out by E+E accredited calibration laboratory guarantees reliable measurement results. The E+E calibration laboratory is accredited for relative humidity of air and supervised by BMWA (Federal Ministry for Economic Affairs). The laboratory calibrates electric instruments measuring humidity in the range of 10% -95 %RH at a temperature of 25 °C ±3 °C. The registration number of the calibration laboratory is ÖKD 23. The ÖKD Calibration Certificates prove traceability to national standards as required in the ISO 9000 and EN 45 000 series of European standards.
The international recognition of the ÖKD calibration certificates is guaranteed by BMWA membership of the European cooperation for Accreditation (EA). At present the calibration services of 24 European countries are members of the EA.
Sixteen of these calibration services, including the BMWA, have concluded a multilateral agreement on the mutual recognition of their calibration certificates.
In addition similar agreements have been concluded with the following accreditation bodies:
| Certificate of Accreditation | Measuring uncertainty The ÖKD accreditation guarantees following outstanding uncertainty of the E+E calibration laboratory. |
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Adjustment – Definition
The output of the instrument under test is compared with a reference. Each deviation is corrected by hardware or software. All E+E instruments are adjusted before delivery. Depending on the instrument, the standard adjustment is made in one or two points.
Calibration – Definition
The output of the instrument under test is compared with a reference The deviations are documented as a calibration certificate, but not changed.
ÖKD certificate – Definition
The ÖKD certificate is issued by the accredited E+E calibration laboratory for measured values between 10 and 95 %RH at a temperature of 25 ±3 °C.
E+E works certificate – Definition
The E+E works certificate is a specific test report according to DIN EN 10204-2.3. It is issued by E+E Elektronik and for measured values between 10 and 95 %RH at a temperature of 23 ±2 °C.
Maintenance of RH Transmitter
Due to the excellent reliability and long term stability under normal operation conditions the E+E relative humidity and temperature transmitters do not require any maintenance. For use in high polluted environment the filter cap shall be periodically exchanged with a new original one.
For high accuracy requirements under extreme humidity and temperature operating conditions the transmitters can be periodically recalibrated. The recalibration interval can be extended by a special E+E low or high humidity calibration. The following graph should be used as guide for the recalibration interval: