Method and apparatus for determining presence of moisture in freeze dryer vacuum line

摘要

A freeze dryer having a collector chamber is provided with a sensor for detecting the presence of moisture in the chamber so that the vacuum pump cannot be operated if moisture is present. The refrigeration system can also be deactivated. This precludes moisture from being pulled into the vacuum pump where it will mix with pump oil and shorten the life of the pump. The moisture sensor is also coupled with a warning circuit which advises the operator that the system is inoperable and is capable of displaying the reason for inoperability.