PRODUCTS

CR-1A CRYOGENIC HYGROMETER

DATA SHEET and USERS MANUAL


CR-1A side view

Benefits of the CR-1A

• Wide Range: down to -120 °C (< 1 ppb)

• Fast Response Time: typically 10-20 seconds

• Inherent Stability and Accuracy

• NIST-traceable

• Very Low Maintenance

The CR-1A is a high performance, cryogenically cooled hygrometer. CR-1 instruments have been routinely used aboard NASA aircraft and elsewhere for years. The CR-1A is a miniaturized version of the original CR-1, and uses a much smaller LN2 dewar. Operating time per filling of LN2 ranges from 6 to 8 hours, depending on the dew points being measured.

A ±0.1% accuracy pressure transducer is included for measuring mixing ratio (ppmv or lbs/MMSCF). There is an optional 4.5 Ah battery pack, and an optional autofill system for continuous use applications.

The CR-1A is designed to operate with virtually no attention. Maintenance demands are minimal, consisting of dewar filling and occasional mirror cleaning as necessary.

CR-1A Hygrometer Specifications

Measurement Range
Dew / frost point temperature -120 to +30°C
Lowest Concentration ppbv
sea level <1
100 psig (7.8 bar) <1
Reading Accuracy °C
Entire Range ±0.15°C
Concentration ±2% of reading
Typical Response Time 10-20 seconds
Operating Range
Temperature -40 to +60°C
Pressure, psia (bar) 0 to 150 psia (0 to 10 bar)
Air / Gas flow range 0.2 to 3 liters/min
Cooling Mechanism 1.0 L Dewar filled with Liquid Nitrogen (LN2) (optoinal autofill system for continuous use)
Power Requirements
Standard 115-230 VAC, 50-400 Hz, <30w
Optional 24-28 VDC, Battery
Outputs 0-10V, 4-20mA, Alarm, RS-232

CR1A_3_new

Note: These are approximate specifications. Exact performance will vary depending on installation and operating environment. The right to make technical changes is reserved.