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new start time. When the new start time is reached, the Tem-
perature Compensated Start mode is set, the fan is started and
the unit controlled as in an occupied state. Once set, Tempera-
ture 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 Economizer Free Cool mode is active
when temperature compensated start begins, the Unoccupied
Free Cool mode will be stopped.
NOTE: The maximum minutes Start Bias can be is 180.
Carrier Comfort Network
®
(CCN) Configuration
It is possible to configure the
Comfort
Link control to partici-
pate as an element of the Carrier Comfort Network (CCN) sys-
tem 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 located in
the local displays at
Configuration
CCN
. See Appendix A.
CCN Address (CCN.A)
This configuration is the CCN address the rooftop is assigned.
CCN Address (CCN.B)
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 (BROD
B.TIM)
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 configura-
tion 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 (BROD
B.OAT)
If this configuration is set to ON, the control will periodically
broadcast its outside-air temperature at a rate of once every 30
minutes.
Global Schedule Broadcast (BROD
B.GS)
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 (BROD
B.ACK)
If this configuration is set to ON, then when any broadcasting is
done on the bus, this device will respond to and acknowledge.
Only one device per bus can be configured for this option.
Schedule Number (SCH.O
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 schedules. 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 (
B.GS
) 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? (SCH.O
HOL.G)
If a device is broadcasting 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 (SCH.O
OV.TL)
This configuration allows the user to decide how long an over-
ride occurs when it is initiated. The override may be config-
ured from 1 to 4 hours. If the time is set to 0, the override func-
tion will become disabled.
Timed Override Hours (SCH.O
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.
SPT Override Enabled? (SCH.O
OV.SP)
If a space sensor is present, then it is possible to override an
unoccupied period by pushing the override button on the T55
or T56 sensor. This option allows the user to disable this func-
tion by setting this configuration to NO.
Demand Limit
Demand Limit Control may override the cooling algorithm to
limit or reduce cooling capacity during run time. The term De-
mand Limit Control refers to the restriction of machine capaci-
ty to control the amount of power that a machine will use. This
can save the owner money by limiting peaks in the power sup-
ply. Demand limit control is intended to interface with an ex-
ternal network system. This is through a CCN Loadshed POC
Device or writing to network points.
To limit stages through network writes, the points Run
Sta-
tus
COOL
MAX.C
and
Run Status
HEAT
MAX.H
are
forced on the network through CCN points MAXCSTGS and
MAXHSTGS respectively. Force these to the desired maxi-
mum stages of cooling/dehumidification and heating, respec-
tively.When there is no force on these points, they automatical-
ly reset to allow all cooling/dehumidification and heating stag-
es to be used. These points are reset at power-on/reset (POR).
When using the Loadshed POC to do Demand Limiting, the
cool and heat stage limits under both Redline and Loadshed
conditions can be set individually with configuration decisions.
If the active stages is greater then the loadshed or redline con-
figurations when a loadshed or redline command is given, the
unit will remove stages.
Configuration
CCN
LDSH
S.GRP
This is the Loadshed Group Number and corresponds to the
loadshed supervisory devices that resides elsewhere on the
CCN network and broadcasts loadshed and redline commands
to its associated equipment parts. This variable will default to
zero which is an invalid group number. This allows the load-
shed function to be disabled until configured.
Configuration
CCN
LDSH
R.MXC
This configuration tells the unit the maximum cooling stages
allowed to be on during a redline condition.
Configuration
CCN
LDSH
S.MXC
This configuration tells the unit the maximum cooling stages
allowed to be on during a loadshed condition.
Configuration
CCN
LDSH
R.MXH
This configuration tells the unit the maximum heating stages
allowed to be on during a redline condition.
Configuration
CCN
LDSH
S.MXH
This configuration tells the unit the maximum heating stages
allowed to be on during a loadshed condition.
The two Demand Limiting methods can be active simultaneous-
ly. The lowest cool and heat stage limits imposed by either meth-
od are applied, and these “effective stage limits” are shown in
the points CSTGLIMT (
Run Status
COOL
LMT.C
) and
HSTGLIMT (
Run Status
HEAT
LMT.H
), respectively. In
Summary of Contents for /50HC 04-28
Page 69: ...69 Fig 24 Typical Control Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Page 70: ...70 Fig 25 Typical Power Diagram for 48HC 04 14 Units 48HC 08 09 shown ...
Page 71: ...71 Fig 26 Typical Control Diagram for 50HC 04 14 Units 50HC 14 shown ...
Page 72: ...72 Fig 27 Typical Power Diagram for 50HC 04 14 Units 50HC 14 Non Humidi MiZer shown ...
Page 73: ...73 Fig 28 Typical Control Diagram 48HC 17 28 Units ...
Page 74: ...74 Fig 29 Typical Control Diagram 50HC 17 28 Units ...
Page 75: ...75 Fig 30 Typical Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Page 76: ...76 Fig 31 Typical Non Humid MiZer Power Diagram and Component Arrangement 48 50HC 17 28 Units ...
Page 89: ...89 Fig 42 Modulating ERV Wiring Schematic ...
Page 90: ...90 Fig 43 EnergyX ERV Control Box Component Layouts ...
Page 101: ...101 Fig 59 Exhaust Fan Assembly Removal Exhaust Fan Assembly ...
Page 141: ......