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93
Fig. 15 —
Humidi-MiZer System Diagram
Temperature Compensated Start
This logic is used when the unit is in the unoccupied state. The
control will calculate early Start Bias time based on Space Tem
-
perature deviation from the occupied cooling and heating set
points. This will allow the control to start the unit so that the space
is at conditioned levels when the occupied period starts. This is re
-
quired for ASHRAE (American Society of Heating, Refrigerating,
and Air-Conditioning Engineers) 90.1 compliance. A space sensor
is required for non-linkage applications.
SETTING UP THE SYSTEM
The settings for temperature compensated start can be found in
the local display under
Configuration
UNIT
.
TCST-Cool Factor (TCS.C)
This is the factor for the start time bias equation for cooling.
TCST-Heat Factor (TCS.H)
This is the factor for the start time bias equation for heating.
NOTE: Temperature compensated start is disabled when these
factors are set to 0.
TEMPERATURE COMPENSATED START LOGIC
The following conditions must be met for the algorithm to run:
• 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 using
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 tempera
-
ture)*
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 Tem
-
perature Compensated Start mode is set (
Operating
Modes
MODE
T.C.ST
), the fan is started and the unit con
-
trolled as in an occupied state. Once set, Temperature Compen
-
sated mode will stay on until the unit goes into the Occupied
mode. The Start Bias Time will be written into the CCN Link
-
age Equipment Table if the unit is controlled in DAV mode. If
the Unoccupied Economizer Free Cool mode is active (
Operat
-
ing Modes
HVAC
= “UNOCC FREE COOL”) when tem
-
perature compensated start begins, the Unoccupied Free Cool
mode will be stopped.
Carrier Comfort Network
®
(CCN)
It is possible to configure the
Comfort
Link controls 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
submenu in the
Configuration
mode.
The major configurations for CCN programming are located in
the local displays at
Configuration
IAQ
CCN
.
See Table 61.
CCN Address (CCNA)
This configuration is the CCN address 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 configura
-
3
4
EXPANSION
INDOOR AIR
EVAPORATOR
5
5'
EVAPORATOR
REHEAT HX
EXPANSION
DEVICE
4'
3'
CHECK VALVE
3-WAY VALVE
3a'
2'
2a'
BYPASS
MODULATING
VALVE
CONDENSER
OUTDOOR AIR
CONDENSER
MODULATING
VALVE
1'
COMPRESSOR
1
2
CONDENSER
OUTDOOR AIR
COMPRESSOR
CIRCUIT B
CIRCUIT A
ITEM
EXPANSION
RANGE UNITS CCN POINT
TCS.C
Temp.Cmp.Strt.Cool Factr 0 to 60
min
TCSTCOOL
TCS.H
Temp.Cmp.Strt.Heat Factr 0 to 60
min
TCSTHEAT
Summary of Contents for WeatherExpert 48N2
Page 135: ...135 Fig 18 48 50N Typical Power Schematic Nominal 075 Ton Unit Shown ...
Page 136: ...136 Fig 19 48 50N Typical Power Schematic Nominal Ton 90 150 Units Shown ...
Page 137: ...137 Fig 20 48 50N Main Base Board Input Output Connections ...
Page 138: ...138 Fig 21 48 50N RXB EXB CEM Input Output Connections a48 9307 ...
Page 139: ...139 Fig 22 48 50N EXV SCB Input Output Connections a48 9308 ...
Page 140: ...140 Fig 23 48N Typical Modulating Gas Heat Unit Control Wiring ...
Page 141: ...141 Fig 24 50N Typical Electric Heat Unit Control Wiring ...
Page 144: ...144 Fig 27 48N Typical Gas Heat Section Wiring Nominal Ton 120 to 150 Units ...
Page 145: ...145 Fig 28 48 50N Typical Power Component Control Wiring 460 v ...
Page 146: ...146 Fig 29 48 50N Component Control Wiring 575 v Nominal Ton 075 to 150 Units ...
Page 147: ...147 Fig 30 48 50N Component Arrangement Power Box ...
Page 148: ...148 Fig 31 48 50N Component Arrangement Control Box ...
Page 240: ...240 APPENDIX D VFD INFORMATION CONT Fig G VFD Bypass Wiring Diagram WHEN USED ...