Metrology Equipments

CVR announces new triple point of water cell. The triple point of water occurs when water coexists within a single glass enclosure (typically glass) in all three of its phases: gas, liquid, and solid. It is defined within the International Temperature Scale as 0.01°C and is the most accurate device used to calibrate or verify thermometers.

Super-Thermometer Readouts

The Super-Thermometer II has the accuracy of 1 ppm and a color screen that tilts to create the best viewing angles.

Super-Thermometers vs. digital multimeters

Good eight-and-a-half-digit multimeters might give you accuracy to ±0.005 °C in the resistance measurement. However, DMMs require separate high-stability current sources, and you have to make EMF offsets, worry about a scheme to switch between forward and reverse current during the measurement, and devise a switch to get a second channel for an external standard resistor.
 
Once you’ve done all of this, you still have to convert resistance to temperature with tedious manual calculations. 

Super-Thermometers do all of this automatically. 

 

Accuracy

In addition, resolution with a 25-ohm SPRT is 0.0001 °C. Comparison calibrations or calibrations against primary standard fixed points are easily performed. Both instruments have two channels for handling two probes at once. Display and record actual temperatures or choose to read the difference between the two directly from the screen. 

CVR Benchtop Temperature/Humidity Generator
Humidity Generator uses a “two-pressure” generation principal, which was originally developed by NIST and involves saturating a stream of air with water vapor at a known temperature and pressure. Relative humidity of the saturated air can be directly calculated through the following formula:



To generate a known humidity, the benchtop controls the pressure ratio (Pc/Ps), utilizing an enhancement factor ratio (fs/fc) and the effective degree of saturation (es/ec). 

Humidity generated by this method is only dependant upon precision measurements of temperature and pressure, so the need to use an expensive chilled-mirror hygrometer as a reference is eliminated, reducing the cost of ownership. The benchtop generates RH with an accuracy of 0.5% over the range –10°C to 70°C and 5% RH to 98% RH. Chamber temperature accuracy is an amazing 0.06°C. With this performance, you can calibrate ambient-measuring, temperature-probes