Buck Research Instruments, LLC Cryogenic Hygrometer CR-2

Benefits of the CR-2 • Wide Range: down to -100 °C (15 ppb) • Fast Response Time: typically 10-20 seconds • Inherent Stability and Accuracy • NIST-traceable • Very Low Maintenance The CR-2 exhibits the same wide range, fast response and high reliability as the CR-1A, but it is designed specifically for aircraft and similar high-stress applications. Instead of using Liquid Nitrogen (LN2), mirror cooling is accomplished using a tactical cryocooler, which is a high-tech device used primarily to cool IR detectors in missiles and tank turrets to LN2 temperatures. Maintenance requirements for the CR-2 are minimal. Aside from occasional mirror cleaning, the cryocooler needs to be renewed every 10,000 hours of use. Both the control circuitry and the sensing assembly are mounted together into a single compact unit. A separate display module is provided that displays the dew / frost point and housekeeping signals. (For aircraft operation, the display module is not required.) The CR-2 include a ±0.1% accuracy pressure transducer, essential in demanding applications for compensating the dew/frost point temperature for minute differences between sample chamber pressure and atmospheric pressure.