Use and calibration of Rosemount ice detectors for meteorological research

Vibrating probe ice detectors made by Rosemount Inc., are used by many researchers for measuring atmospheric icing rates and cloud liquid water contents. The vibration frequency of the probe decreases as ice accretes on it, until the probe is deiced at a factory-set frequency. Rosemount ice detectors are favored because they are readily available, easy to install and simple to operate. They are designed to be used as warning systems for incipient aircraft and antenna icing, and not as precisely calibrated scientific instruments. Calibration cannot be user adjusted, but it can be measured and must be periodically checked if the ice detector is to be used in scientific studies. efly describe three models of Rosemount ice detectors that CRREL has used. Methods for collecting and processing the data from these ice detectors are described and evaluated. Procedures developed at CRREL for calibrating Rosemount detectors against a rotating multicylinder in natural icing conditions are presented. Results of calibrations of two model 872B12 Rosemount ice detectors with the rotating multicylinder are presented and discussed. Use of the ice detector record to calculate cloud liquid water content is described.