Precise calibration for all resistance thermometers – flexible, accredited, reliable
We calibrate your resistance thermometers (temperature sensors such as Pt100, Pt25, etc.) and direct-reading measuring instruments using state-of-the-art methods – optionally by comparison or fixed-point calibration. Our accredited laboratory (DIN EN ISO/IEC 17025) provides you with internationally recognized calibration certificates (DAkkS compliant) with individually suited measurement uncertainties – precisely tailored to your application.
Our Services
Accredited calibration of resistance thermometers and direct-reading measuring instruments
Temperature range: -196°C to +961°C – full coverage of ITS-90
Calibration methods: Fixed-point calibration at ITS-90 fixed points or comparison calibration
Proficiency testing according to DIN EN ISO/IEC 17043
Repair service for thermometers in our own manufactory
Your advantages at a glance
Various calibration methods
The choice is yours:
Fixed-point calibration
at melting points
(economical, low measurement uncertainty)
Comparison calibration
(freely selectable measurement points, cost-effective)
Short turnaround times of 5 working days
→ Minimize downtime – your resistance thermometers are quickly back in use.
Low measurement uncertainties
→ Benefit from the highest precision:
We get the best out of your thermometer.
Everything from a single source
→ Complete package from calibration and proficiency testing to repair – all at Klasmeier.
Central location in Fulda
→ Perfect accessibility – drop off your thermometer in person or use our secure courier service.
Paperless documentation
→ Accessible at any time, legally signed.
Full transparency and security via our modern cloud solution.
Measurement uncertainties for an accredited calibration of resistance thermometers according to DIN EN ISO/IEC 17025 (DAkkS)
| Measuring range | Method | Measurement uncertainty |
|---|---|---|
| -189.3442°C to 0°C | DKD-R 5-1 Fixed points: Ar, Hg, TPW | 5.5 mK |
| -38.8344°C to 29.7646°C | DKD-R 5-1 Fixed points: Hg, TPW, Ga | 3.5 mK |
| 0°C to 29.7646°C | DKD-R 5-1 Fixed points: TPW, Ga | 2.5 mK |
| 0°C to 156.5985°C | DKD-R 5-1 Fixed points: TPW, In melting points | 5.5 mK |
| 0°C to 231.928°C | DKD-R 5-1 Fixed points: TPW, In, Sn melting points | 7.0 mK |
| 0°C to 419.527°C | DKD-R 5-1 Fixed points: TPW, Sn, Zn melting points | 12 mK |
| 0°C to 660.323°C | DKD-R 5-1 Fixed points: TPW, Sn, Zn, Al melting points | 20 mK |
| Measuring range | Method | Measurement uncertainty |
|---|---|---|
| -196°C | DKD-R 5-1 (DIN EN IEC 60751) in liquid nitrogen with compensation block | 15 mK |
| -180°C to -80°C | DKD-R 5-1 (DIN EN IEC 60751) in cryostat | 60 mK |
| -80°C to -60°C > -60°C to 90°C | DKD-R 5-1 (DIN EN IEC 60751) in calibration furnace or liquid bath | 15 mK 10 mK |
| > 90°C to 200°C > 200°C to 500°C > 500°C to 660°C > 660°C to 962°C | DKD-R 5-1 (DIN EN IEC 60751) in calibration furnace, liquid or solid bath | 30 mK 40 mK 50 mK 0.15 K |
Minimum requirements for the calibration of resistance thermometers
| Sensor type | Temperature range | Minimum immersion depth | Max. diameter | Remark |
| PRT | -196°C | 300 mm | <8 mm | Nitrogen boiling point |
| PRT | -180°C to -81°C | 480 mm | <7.5 mm | Low-temperature cryostat |
| PRT | -80°C to 230°C | 100 mm | – | Calibration bath, good homogeneity |
| PRT | 231°C to 700°C | 300 mm | <8 mm | Calibration furnace |
| PRT | 701°C to 962°C | 450 mm | <8 mm | High temperatures, greater depth required |
| Thermocouple | 196°C | 300 mm | <8 mm | Nitrogen boiling point |
| Thermocouple | -180°C to -81°C | 480 mm | <7.5 mm | Low-temperature cryostat |
| Thermocouple | -80°C to 230°C | 100 mm | – | Calibration bath |
| Thermocouple | 231°C to 1200°C | 190 mm | <8 mm | Calibration furnace |
| Au/Pt & Pt/Pd | 0°C to 1200°C | 480 mm | <8 mm | Noble metal thermocouple |
Why our fixed-point calibration is particularly reliable
We calibrate not only SPRTs but also all types of resistance thermometers at official ITS-90 temperature fixed points – with one clear goal: reliable, long-term stable measurement results for your applications.
Our procedure includes:
- Annealing at the highest operating temperature
- Determination of aging drift at the triple point of water
- Investigation of self-heating errors and pressure effects
- Hysteresis testing and ITS-90 characteristic curve analysis
The result: A fully documented DAkkS-compliant calibration certificate that is internationally recognized – ideal for demanding applications and audits.
Calibration possible from small immersion depths
Thanks to a specially developed calibration process at slim temperature fixed points and our modern ISO Tower technology, we calibrate your resistance thermometers from an immersion depth of just 300 mm – with outstanding measurement uncertainty.
Comparison of SPRTs with IPRTs at temperature fixed points
When calibrating reference thermometers at ITS-90 temperature fixed points, the question of the required calibration points is frequently raised. To ensure that the number of ITS-90 temperature fixed points is also sufficient in the higher temperature range, we have conducted extensive investigations. The following graphic shows the result of these investigations, comparing a standard platinum resistance thermometer (SPRT) with a reference thermometer.
The temperature difference shows that the maximum characteristic curve deviation of approx. 25 mK lies within the measurement uncertainty. For accredited calibrations according to DIN EN ISO/IEC 17025 (DAkkS) in the higher temperature range, we perform a plausibility check of the characteristic curve in addition to the aforementioned investigations. The test temperature lies between the fixed-point temperatures.
Klasmeier Cloud Digital Archive:
Calibration documents accessible quickly and easily
The Klasmeier Cloud – the perfect filing system for all calibration documents. On all devices calibrated by Klasmeier, you will find a QR code that takes you quickly and easily to our digital archive.
Particularly practical: In addition to all calibration documents, you will always find the contact details of the respective contact person at Klasmeier. This way, even in five or more years, you can find the information you need with one click if you have questions about your calibration product.
Klasmeier – because precise temperature measurement is a matter of trust.
Your advantages in detail:
In-house manufactory & repair service
→ Thermometer repair directly at our facility – fast & reliable
Proficiency testing + calibration + consulting
→ Everything from a single source – fully auditable
Central location in Germany
→ Easily accessible – or use our GO transport service
Digital, signed calibration certificates
→ Always available, tamper-proof, legally secure
Added value for audits & consulting
We can offer you support with audit preparations:
Accredited calibrations across the entire ITS-90 range
→ This ensures you are perfectly prepared for your next assessment.
Proficiency testing to confirm your measurement uncertainties
Practical tips and advice from an accredited laboratory
→ So that your temperature measurement technology convinces not only on paper but also in everyday practice
Gemeinsam die richtige Lösung für Sie finden
Sprechen Sie direkt mit unserem Experten!
Ihr Ansprechpartner für Kalibrierdienstleistungen
und Eignungsprüfungen:
Boris Kalb
Request calibration
What are the costs for calibrating resistance thermometers?
When you have a platinum resistance thermometer (PRT) calibrated in our accredited calibration laboratory, the costs always consist of two components:
1. the base costs for the calibration
2. the costs per selected calibration point
Additionally, depending on the temperature range, nitrogen costs may apply.
1. Base costs (mandatory part of every calibration)
- KK-1436 – Base costs comparison calibration for PRT: €150
The base costs include:
• Creation of the accredited calibration certificate according to DIN EN ISO/IEC 17025 (DAkkS)
• Stabilization of the thermometer through thermal treatment
• Determination of self-heating and hysteresis (both are documented in the calibration certificate)
• Inspection and evaluation by our specialists
2. Costs per calibration point
Depending on the temperature range in which you use your thermometer, suitable calibration points can be selected. We perform calibrations starting from at least 3 calibration points – 5 calibration points are recommended for reliable characterization.
- kk-1476 – Calibration point -180°C to -81°C: €205
(additional nitrogen costs will be charged, see below) - kk-1437 – Calibration point -196°C (nitrogen boiling point): €135
(additional nitrogen costs will be charged, see below) - kk-1438 – Calibration point -80°C to +230°C: €110
- kk-1439 – Calibration point +231°C to +962°C: €135
3. Nitrogen costs (only for low temperatures)
For calibrations in a cryostat or at -196°C, the use of liquid nitrogen is necessary. This is charged as a flat rate per calibration: - kk-1477 – Nitrogen (50 l) for cryostat: €515 (for measurements in the range -180°C to -81°C)
- kk-1478 – Nitrogen (10 l) for -196°C calibration: €105
4. Example calculation
A typical PRT is calibrated at, for example, 5 calibration points: - 0°C, 100°C, 200°C, 400°C, 660°C
The costs are then calculated from: - €150 base costs (kk-1436)
- 5 × €110–135 depending on the temperature range
- With a selection of 3 calibration points in the medium range (e.g., 0°C, 100°C, 200°C), the cost is approximately €480 net.
5. Volume discounts
If several thermometers are calibrated at the same temperatures simultaneously, we can offer you attractive volume discounts: - from 5 units: 15%
- from 10 units: 30%
Summary
The total cost of a calibration therefore depends on: - the one-time base costs (kk-1436)
- the number and selection of calibration points (kk-1437 to kk-1439, kk-1476)
- if applicable, the nitrogen costs (kk-1477, kk-1478)