Q&A.docx

Questions -- What is the cycle time between temperatures of -60 degrees and +160 degrees?

Is the cycle time from an extreme to room temperature, or from one extreme to the other

Answers -- To address the temperature question the contractor must understand that the two different temperatures i.e. high and low, is not a cycle they are the high temperature that the system must be able to hold. The system would be started the day before and run all night to get to the temperature for testing the next day. It is the same for the low temperature, with an exception that we can use CO2 to run the temperature down faster and then hold with the system. I don't know of any requirement that they have to get the temperature down or up within a set time. If they build the system to provide the required air flow and be able to retain the temperature our system is what will drive the time to get to that temperature of high or low. What they are to provide is the box, duct work, and the other listed deliverables as stated in the requirements. Is this contractor attempting to build a complete new system? If so they do not understand what we are asking for. The MIL-STD-810 states that the max temperature change is no more than 5 deg. F per min. when going from room temperature to high or low temperature.