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Occupancy schedule – Carrier 19XL User Manual

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register up to 32,767 hours before it rolls over to zero.

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 18

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