- Other Fluke companies:
- Fluke
- Fluke Biomedical
- Fluke Networks
- Fluke Process Instruments
ITS-90 Reference Function Calculator
Select one of the 12 ITS-90 fixed-points from the keypad, or type a temperature between 259.3467 °C (13.8033 K) and 961.78 °C (1234.93 K) into the Temperature window and press Calculate. The calculator will produce the ITS-90 reference function value Wr) and the sensitivity (dT/dW) for that temperature. Wr is a resistance ratio (RT90/RTPW) that represents the ideal behavior of platinum resistance thermometers that meet the ITS-90 definition. dT/dW describes the slope of the reference function at the selected temperature and can be used to calculate the impact of an incremental change in temperature on Wr.
ITS-90 fixed-point temperatures occur at the boundaries between solid, liquid, and vapor phases of matter. They include triple points (Tp), freezing points (Fp) and melting points (Mp). For example, the triple point of water (H20 Tp, or TPW) is the temperature (0.010 °C) where all three phases (solid, liquid, and vapor) are in equilibrium together. FpZn is the freezing point temperature (419.527 °C) where Zn makes a transition from liquid to solid. |
- Home
- Products
- New Products
- Electrical Calibration
- RF Calibration
- Data Acquisition and Test Equipment
- Temperature Calibration
- Humidity Calibration
- Pressure Calibration
- Flow Calibration
- Process Calibration Tools
- Calibration Software
- Service and Support
- All Calibration Instruments
- Handheld Test Tools
- Purchase Info
- News
- Training and Events
- Literature and Education
- Service and Support
- Service Request (RMA)
- Service Plans
- Technical Support
- Knowledge Base
- Accreditations
- Authorized Service Centers
- Calibration Certificates
- Community Forum
- My MET/SUPPORT
- Product Manuals (User Guides)
- Register Products
- Safety Data Sheets (SDS)
- Recycle Program
- Safety, Service, and Product Notices
- Software Downloads
- Warranties
- Tools
- About Us

We'd like your feedback.
You can help us improve our website »
Thank you!
If you purchased an item from a Fluke authorized distributor, please contact them directly with questions regarding Certificates of Calibration or other documentation.
Support requests for items purchased from, or serviced directly by Fluke and general Metrology questions can be submitted via our online Support Request form and a Fluke representative will be in contact with you.