OMEGA's standard temperature and humidity recorder,
the CT485B, is a perfect fit for monitoring air conditions inside the stock
room. But in order to track the number of times the stock room doors were
opened, an additional circuit was added to the CT485B. It was triggered
by a contact closure on the door.
A modification was also made to the alarm output of the CT485B. Every
time the door was opened, the blue humidity pen would dip to zero, in effect
adding an "event recorder" function to the unit.
With all the pertinent information contained on a single chart, the
supervisor was able to adjust climate controls in proportion to the frequency
of the number of visits to the stock room. This prevented the temperature
and humidity from dropping below prescribed limits.