NOTE: This is true only if the occupied period starts at 00:00 (midnight). If the occupied period starts at a time other than midnight, then the occupied period must end at 00:00 hours (midnight) and new occupied period must be programmed to start at 00:00 in order for the chiller to stay in the occu- pied mode past midnight.

The time schedule can be overridden to keep unit in oc- cupied mode for one, 2, 3, or 4 hours on a one-time basis. See Example 9.

All subfunctions of schedule function are password

protected except the override subfunction, . Pass-

word entry into subfunctions through ,

is done through service function. See page 43, logging on/ logging off.

Figure 10 shows a schedule for an office building with the chiller operating on a single set point schedule. The sched- ule is based on building occupancy with a 3-hour off-peak cool-down period from midnight to 3 a.m. following the week- end shutdown. To learn how this sample schedule would be programmed, see Example 9.

NOTE: This schedule was designed to illustrate the pro- gramming of the schedule function and is not intended as a recommended schedule for chiller operation.

Example 9 Ð Using the Schedule Function

KEYPAD

DISPLAY

COMMENT

ENTRY

 

 

 

 

 

 

OVRD 0

No scheduled override

 

in effect

 

 

 

OVRD 3

3 hours override in effect

 

OVRD 0

Override cancelled

 

CLOCK 0

Schedule function is inactive

 

CLOCK 1

Schedule function is enabled

 

through local unit clock

 

 

 

 

 

PROGRAMMING PERIOD 1:

 

Example 9 Ð Using the Schedule Function (cont)

KEYPAD

DISPLAY

COMMENT

ENTRY

 

 

 

 

 

PROGRAMMING PERIOD 2:

 

 

 

 

 

 

PERIOD 2

De®ne schedule period 2

 

OCC 00.00

Start of occupied time

 

OCC 7.00

Occupied time will start

 

at 7:00 a.m.

 

 

 

 

Start of unoccupied time

 

UNO 00.00

(end of period). For this

 

example, period 2 should

 

 

end at 18:00 (6:00 p.m.)

 

UNO 18.00

Period 2 ends at 18:00

 

(6:00 p.m.)

 

 

Monday is now ¯agged no

 

MON NO

for period 2. To put period 2

 

into effect on Monday,

 

 

 

 

Monday must be ¯agged yes

 

MON YES

Monday is now ¯agged for

 

period 2 to be in effect

 

 

 

 

Tuesay is now ¯agged no

 

 

for period 2. To put period 2

 

TUE NO

into effect on Tuesday,

 

 

Tuesday must be ¯agged

 

 

yes

 

TUE YES

Tuesday is now ¯agged for

 

period 2 to be in effect

 

 

 

 

For this example, period 2

 

 

is to be in effect only on

 

 

Monday and Tuesday.

 

WED YES

All other days must be

 

checked to be sure that

 

 

 

 

they are ¯agged no. If

 

 

a day is ¯agged yes,

 

 

change to no

 

WED NO

Wednesday is now ¯agged

 

no for period 2

 

 

 

 

 

 

PERIOD 3

De®ne schedule

 

period 3

 

 

 

OCC 00.00

Start of occupied

 

time

 

OCC 7.00

Occupied time will start

 

at 7:00 a.m.

 

 

 

 

Start of unoccupied time

 

UNO 00.00

(end of period 3). For this

 

example, period 3 should

PERIOD 1

OCC 00.00

UNO 00.00

UNO 3.00

MON NO

MON YES

TUE YES

TUE NO

De®ne schedule period 1. Start of occupied time

For this example, ®rst period should start here (at midnight) so no entry is needed

Start of unoccupied time (end of period). For this example, period 1 should end at 3:00 a.m.

Period 1 ends at 3:00 a.m.

Monday is now ¯agged no for period 1. To put period 1 into effect on Monday, Monday must be ¯agged yes

Monday is now ¯agged for period 1 to be in effect

For this example, period 1 is to be in effect on Monday only. All other days must be checked to be sure that they are ¯agged no. If any day is ¯agged yes, change to no

Tuesday is now ¯agged no for period 1

 

end at 21:30 (9:30 p.m.)

UNO 21.30

Period 3 ends at 21:30

(9:30 p.m.)

 

Check to be sure that

MON NO

Monday and Tuesday are

 

¯agged no for period 3

TUE NO

 

WED NO

Wednesday is ¯agged

no, change to yes

 

WED YES

Wednesday is now

¯agged yes for period 3

 

THUR NO

Check to be sure that all

other days are ¯agged no

 

FRI NO

 

SAT NO

 

SUN NO

 

CCN Ð Carrier Comfort Network

46

Page 46
Image 46
Carrier 30GN040-420 Example 9 Ð Using the Schedule Function, Keypad Display Comment Entry, Programming Period

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