Carrier 17/19EX - Manual (Page 77)

The chiller also maintains a start-to-start timer and a stop-to-start timer. These timers limit
how soon the machine can be started. See the Start-Up/Shutdown/Recycle Sequence section
for operational information.
Occupancy Schedule
This schedule determines when the chiller is either occupied or unoccupied.
Each schedule consists of from one to 8 occupied/unoccupied time periods, set by the
operator. These time periods can be enabled to be in effect, or not in effect, on each day of the
week and for holidays. The day begins with 0000 hours and ends with 2400 hours. The machine
is in OCCUPIED mode unless an unoccupied time period is in effect.
The machine will shut down when the schedule goes to UNOCCUPIED. These schedules
can be set up to follow the building schedule or to be 100% OCCUPIED if the operator wishes.
The schedules also can be bypassed by forcing the Start/Stop command on the PIC Status
screen to start. The schedules also can be overridden to keep the unit in an OCCUPIED mode
for up to 4 hours, on a one-time basis.
Figure 19 shows a schedule for a typical office building time schedule, with a 3-hour, off-peak
cool down period from midnight to 3 a.m., following a weekend shutdown. Example: Holiday
periods are unoccupied 24 hours per day. The building operates Monday through Friday, 7:00
a.m. to 6:00 p.m., with a Saturday schedule of 6:00 a.m. to 1:00 p.m., and includes the Monday
midnight to 3:00 a.m. weekend cool-down schedule.