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Altitude.......in feet: (ALTI)
As the control does not include a barometric pressure sensor to
thoroughly define the calculation of enthalpy and cfm, the con
-
trol does include an altitude parameter, which will serve to set
up a “mean” barometric pressure for use to calculate with. The
effect of barometric pressure in these calculations is not great,
but could have an effect, depending on the installed elevation
of the unit. Basically, if the rooftop is installed at a particularly
high altitude and enthalpy or cfm are being calculated, set this
configuration to the current elevation of the installed rooftop.
Start Up Delay Time (DLAY)
This option inhibits the unit from operating after a power reset.
The configuration may be adjusted from 0 to 900 seconds of delay.
Auxiliary Relay Output Configuration (AUX.R)
This configuration allows the user to configure the function of
the auxiliary relay output. The output is 1.4 vac, 5 va maximum.
The configuration can be set from 0 to 3. If
AUX.R
is set to 0,
the auxiliary relay contact will be energized during an alarm.
The output can be used to turn on an indicator light or sound an
alarm in a mechanical room. If
AUX.R
is set to 1, the auxiliary
relay will energize when the controls determine dehumidifica
-
tion/reheat is needed. The relay is wired to a third-party dehu
-
midification/reheat device and energizes the device when need
-
ed. If
AUX.R
is set to 2, the auxiliary relay will energize when
the unit is in the occupied state. The relay could then be used to
control lighting or other functions that need to be on during the
occupied state. If
AUX.R
is set to 3, the auxiliary relay will ener
-
gize when the supply fan is energized (and, if equipped with a
VFD, the VFD output is not 0%). The default is 0.
Space Temp Sensor (SPT.S)
If a space temperature sensor is installed (T55/T56), enable
this configuration.
Space Temp Offset Sensor (SP.O.S)
If a T56 sensor is installed with the space temperature offset
slider, enable this configuration.
Space Temp Offset Range (SP.O.R)
If a space temperature offset sensor is installed, it is possible to
configure the “sweep” range of the slider by adjusting this
“range” configuration.
Space Air RH Sensor (SRH.S)
If a space relative humidity sensor is installed, enable this
configuration.
Return RH Sensor (RRH.S)
If a return air relative humidity sensor is installed, enable this
configuration.
Mixed RH Sensor (MRH.S)
If a mixed air relative humidity sensor is installed, enable this
configuration.
Model Number (MD.MN)
The 18-digit model number of the unit.
Factory Reset (F.RST)
Performing a factory reset will reset all configurable parame
-
ters back to the original settings as when the unit left the facto
-
ry. To perform factory reset, set
F.RST
to “YES.” When reset is
complete,
F.RST
will change back to “NO.”
Cooling Control
The N Series
Comfort
Link controls offer 2 basic control ap
-
proaches to mechanical cooling: multi-stage cooling (CV) and
multiple stages of cooling (VAV). In addition, the
Comfort
Link
controls offer the ability to run multiple stages of cooling for
either a space temperature sensor or thermostat by controlling
the unit to either a low or high cool supply air set point.
SETTING UP THE SYSTEM
The control type (
Configuration
UNIT
C.TYP
) deter
-
mines the selection of the type of cooling control, as well as the
technique for selecting a cooling mode. Unit staging tables are
shown in Appendix C.
NOTE: Whether a unit has a VFD or a supply fan installed for
static pressure control has no effect on configuration of the ma
-
chine control type (
C.TYP
). No matter what the control type, it
is possible to run the unit in either CV or VAV mode provided
there are enough stages to accommodate lower air volumes for
VAV operation. Refer to the section on static pressure control
on page 69 for information on how to set up the unit for the
type of supply fan control desired.
Machine Control Type (Configuration
UNIT
C.TYP)
The most fundamental cooling control configuration is located
under
Configuration
UNIT
.
*This default is model-number-dependent.
This configuration defines the technique and control source re
-
sponsible for selecting a cooling mode and in determining the
method by which compressors are staged. The control types are:
•
C.TYP
= 1 (VAV-RAT) and
C.TYP
= 2 (VAV-SPT)
Both of these configurations refer to standard VAV opera
-
tion. If the control is occupied, the supply fan is run continu
-
ously and return-air temperature will be used for both in the
determination of the selection of a cooling mode. VAV-SPT
differs from VAV-RAT only in that during the unoccupied
period, space temperature will be used instead of return-air
temperature to start the fan for 10 minutes before the return-
air temperature is allowed to call out any mode.
•
C.TYP
= 3 (TSTAT – MULTI)
This configuration will force the control to monitor the
thermostat inputs to make a determination of mode. Unlike
traditional 2-stage thermostat control, the unit is allowed to
use multiple stages of cooling control and perform VAV
style operation. The control will be able to call out a LOW
COOL or a HIGH COOL mode and maintain a low or high
cool supply air set point.
•
C.TYP
= 4
(SPT – MULTI)
This configuration will force the control to monitor a space
temperature sensor to make a determination of mode. Un
-
like traditional 2-stage space temperature control, the unit
is allowed to use multiple stages of cooling control and
perform VAV style operation. The control will be able to
call out a LOW COOL or a HIGH COOL mode and main
-
tain a low or high cool supply air set point.
MACHINE DEPENDENT CONFIGURATIONS
Some configurations are linked to the physical unit and must
not be changed. The configurations are provided in case a field
replacement of a board occurs and the settings are not pre
-
served by the download process of the new software. The fol
-
lowing configurations apply to all machine control types
(
C.TYP
). These configurations are located at the local display
under
Configuration
UNIT
.
See Table 26.
Table 26 —
Machine Dependent Configurations
*Dependent on unit.
ITEM
EXPANSION
RANGE
CCN
POINT
DEFAULTS
UNIT
UNIT CONFIGURATION
C.TYP
Machine Control Type 1 to 4
CTRLTYPE
*
ITEM
EXPANSION
RANGE
CCN
POINT
DEFAULTS
UNIT
UNIT CONFIGURATION
SIZE
Unit Size (75-150)
75-150
UNITSIZE
*
Содержание WeatherExpert 48N2
Страница 135: ...135 Fig 18 48 50N Typical Power Schematic Nominal 075 Ton Unit Shown ...
Страница 136: ...136 Fig 19 48 50N Typical Power Schematic Nominal Ton 90 150 Units Shown ...
Страница 137: ...137 Fig 20 48 50N Main Base Board Input Output Connections ...
Страница 138: ...138 Fig 21 48 50N RXB EXB CEM Input Output Connections a48 9307 ...
Страница 139: ...139 Fig 22 48 50N EXV SCB Input Output Connections a48 9308 ...
Страница 140: ...140 Fig 23 48N Typical Modulating Gas Heat Unit Control Wiring ...
Страница 141: ...141 Fig 24 50N Typical Electric Heat Unit Control Wiring ...
Страница 144: ...144 Fig 27 48N Typical Gas Heat Section Wiring Nominal Ton 120 to 150 Units ...
Страница 145: ...145 Fig 28 48 50N Typical Power Component Control Wiring 460 v ...
Страница 146: ...146 Fig 29 48 50N Component Control Wiring 575 v Nominal Ton 075 to 150 Units ...
Страница 147: ...147 Fig 30 48 50N Component Arrangement Power Box ...
Страница 148: ...148 Fig 31 48 50N Component Arrangement Control Box ...
Страница 168: ...168 Fig 47 Sensor and Ignition Position Fig 48 Combustion Blower Details SENSOR DETAILS IGNITION DETAILS ...
Страница 240: ...240 APPENDIX D VFD INFORMATION CONT Fig G VFD Bypass Wiring Diagram WHEN USED ...