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68
TEMPERATURE COMPENSATED START LOGIC — The
following conditions must be met:
• Unit is in unoccupied state.
• Next occupied time is valid.
• Current time of day is valid.
• Valid space temperature reading is available (sensor or
DAV-Linkage).
The algorithm will calculate a Start Bias time in minutes us-
ing the following equations:
If (space temperature > occupied cooling set point)
Start Bias Time = (space temperature – occupied cooling set
point)*
TCS.C
If (space temperature < occupied heating set point)
Start Bias Time = (occupied heating set point – space
temperature)*
TCS.H
When the Start Bias Time is greater than zero the algorithm
will subtract it from the next occupied time to calculate the new
start time. When the new start time is reached, the Temperature
Compensated Start mode is set (
Operating Modes
→
MODE
→
T.C.ST
), the fan is started and the unit controlled as in an occu-
pied state. Once set, Temperature Compensated mode will stay
on until the unit goes into the Occupied mode. The Start Bias
Time will be written into the CCN Linkage Equipment Table if
the unit is controlled in DAV mode. If the Unoccupied Econo-
mizer Free Cool mode is active (
Operating Modes
→
HVAC
=
“UNOCC FREE COOL”) when temperature compensated
start begins, the Unoccupied Free Cool mode will be stopped.
Carrier Comfort Network
®
(CCN) —
It is possible
to configure the
Comfort
Link™ control to participate as an ele-
ment of the Carrier Comfort Network (CCN) directly from the
local display. This section will deal with explaining the various
programmable options which are found under the
CCN
sub-
menu in the
Configuration
mode.
The major configurations for CCN programming are locat-
ed in the local displays at
Configuration
→
CCN
.
See Table 80.
CCN Address (
CCNA
) — This configuration is the CCN ad-
dress the rooftop is assigned.
CCN Bus Number (
CCNB
) — This configuration is the CCN
bus the rooftop is assigned.
CCN Baud Rate (
BAUD
) — This configuration is the CCN
baud rate.
CCN Time/Date Broadcast (
TM.DT
) — If this configuration
is set to ON, the control will periodically send the time and date
out onto the CCN bus once a minute. If this device is on a CCN
network then it will be important to make sure that only one
device on the bus has this configuration set to ON. If more than
one time broadcaster is present, problems with the time will
occur.
NOTE: Only the time and date broadcaster can perform
daylight savings time adjustments. Even if the rooftop is stand
alone, the user may want to set this to ON to accomplish the
daylight/savings function.
CCN OAT Broadcast (
OAT.B
) — If this configuration is set
to ON, the control will periodically broadcast its outside-air
temperature at a rate of once every 30 minutes.
CCN OARH Broadcast (
ORH.B
) — If this configuration is
set to ON, the control will periodically broadcast its outside air
relative humidity at a rate of once every 30 minutes.
CCN OAQ Broadcast (
OAQ.B
) — If this configuration is set
to ON, the control will periodically broadcast its outside air
quality reading at a rate of once every 30 minutes.
Global Schedule Broadcast (
G.S.B
) — If this configuration is
set to ON and the schedule number (
SCH.N
) is between 65 and
99, then the control will broadcast the internal time schedule
once every 2 minutes.
CCN Broadcast Acknowledger (
B.ACK
) — If this configu-
ration is set to ON, then when any broadcasting is done on the
bus, this device will respond to and acknowledge. Only one de-
vice per bus can be configured for this option.
Schedule Number (
SCH.N
) — This configuration determines
what schedule the control may follow.
SCH.N
= 0
The control is always occupied.
SCH.N
= 1
The control follows its internal time sched-
ules. The user may enter any number
between 1 and 64 but it will be overwritten
to “1” by the control as it only has one
internal schedule.
SCH.N
= 65-99 The control is either set up to receive to a
broadcasted time schedule set to this
number or the control is set up to broadcast
its internal time schedule (
G.S.B
) to the
network and this is the global schedule
number it is broadcasting. If this is the case,
then the control still follows its internal time
schedules.
Accept Global Holidays? (
HOL.T
) — If a device is broad-
casting the time on the bus, it is possible to accept the time yet
not accept the global holiday from the broadcast message.
Override Time Limit (
O.T.L
) — This configuration allows
the user to decide how long an override occurs when it is initi-
ated. The override may be configured from 1 to 4 hours. If the
time is set to 0, the override function will become disabled.
Timed Override Hours (
OV.EX
) — This displays the current
number of hours left in an override. It is possible to cancel an
override in progress by writing “0” to this variable, thereby
removing the override time left.
Table 80 — CCN Configuration
ITEM
EXPANSION
RANGE
UNITS
POINT
DEFAULT
CCN
CCN CONFIGURATION
CCNA
CCN Address
1 - 239
CCNADD
1
CCNB
CCN Bus Number
0 - 239
CCNBUS
0
BAUD
CCN Baud Rate
1 - 5
CCNBAUDD
3
BROD
CCN BROADCST DEFINITIONS
TM.DT
CCN Time/Date Broadcast
ON/OFF
CCNBC
On
OAT.B
CCN OAT Broadcast
ON/OFF
OATBC
Off
ORH.B
CCN OARH Broadcast
ON/OFF
OARHBC
Off
OAQ.B
CCN OAQ Broadcast
ON/OFF
OAQBC
Off
G.S.B
Global Schedule Broadcst
ON/OFF
GSBC
Off
B.ACK
CCN Broadcast Ack'er
ON/OFF
CCNBCACK
Off
SC.OV
CCN SCHEDULES-OVERRIDES
SCH.N
Schedule Number
0 - 99
SCHEDNUM
1
HOL.T
Accept Global Holidays?
YES/NO
HOLIDAYT
No
O.T.L.
Override Time Limit
0 - 4
HRS
OTL
1
OV.EX
Timed Override Hours
0 - 4
HRS
OVR_EXT
0
SPT.O
SPT Override Enabled ?
YES/NO
SPT_OVER
Yes
T58.O
T58 Override Enabled ?
YES/NO
T58_OVER
Yes
GL.OV
Global Sched. Override ?
YES/NO
GLBLOVER
No
Summary of Contents for WEATHERMAKER 48AJ020
Page 95: ...95 Fig 13 Typical Main Control Box Wiring Schematic A48 7787 ...
Page 96: ...96 TO NEXT PAGE Fig 14 Auxiliary Control Box Wiring Schematic A48 7294 ...
Page 98: ...98 Fig 15 Typical 2 Stage Gas Heat Wiring Schematic Size 051 and 060 Units Shown A48 6866 ...
Page 102: ...102 TO NEXT PAGE Fig 18 Typical Power Schematic Size 051 and 060 Units Shown A48 7298 ...
Page 104: ...104 Fig 19 Controls Option Wiring Schematic A48 7810 ...
Page 105: ...105 Fig 20 Small Chassis Component Location Size 020 035 Units A48 7301 ...
Page 106: ...106 Fig 21 Large Chassis Component Locations Size 036 060 Units A48 7302 ...