Information
Laboratory Product > Glass Thermometer
Important Notes
Stabilization
Prior to filling with mercury the thermometers have to undergo a heat treatment (stabilization or artificial aging) which will prove successful only if it is carried out by expérience and by applying suitable apparatus. We have both.
Correction of emergent column
Glass thermometers are delivered for "total immersion" if not otherwise expressly noted down in our web page. If such a thermometer is used only partially immersed, then the température reading has to be corrected.
For mercury-filled thermometers the correction with sufficient accuracy is calculated as follows:
k= n(t-t')/6000
You will find more details on this on our Works certificates, please request the forms for those.
PTB-Specifications
The term «suitable for government testing«, is to say that such thermometers and hydrometers comply with ail requirements of the German gauging office (PTB). This can be taken for granted.
Limits of Error for Thermometers
Under the régulations No EO 14-1 of the German »Eichordnung» the following limits of error of the most current thermometers are laid down.
The limits of error for thermometers with wetting liquid calibrated for total immersion are as follows:
The limits of error for thermometers filled with liquid which does not wet and designed for total immersion.
Official certificate
Thermometers meeting the manifold requirements of the German calibration-spécifications are officially stamped by the gauging office. Generally they are accompanied by an official certificate. In this catalogue, such thermometers are termed »government tested, with certificate».
The «Physikalisch-Technische Bundesanstalt« (PTB) domiciled at Braunschweig calibrates only on request and invoices charges as per expenditure of work.
In principle, calibration is made by régional gauging offices which are located throughout the Fédéral Republic of Germany (e. g. Wertheim, Darmstadt, München, Berlin).
We reserve the right to choose the gauging office.
In the event of controversies abroad concering the quality of our thermometers and hydrometers arbitration is re served to with the linked gauging offices.
Top finish of Thermometers
Ail types meet the requirements of DIN 12 770.
