A customer wanted to optimize the ventilation in subway trains using closed loop control of carbon dioxide. Normally the automatic calibration that compensate for sensor drift operate on an 8-day period since most office buildings have a one week cycle in population, but subway trains operate every day of the week. Instead they are taken out for maintenance once a day. Hence our customer needed a 48-hour period for the automatic drift correction.
The time change as well as a new maximum rate for drift compensation was implemented by one of our own software engineers. The change was also found to be within the normal operation of the sensor.
Since it was a minor adaption and the customer agreed to buy a certain volume it was no additional cost for the customer.