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28
Configuration
ECON
EC.MN
should always be set for the
minimum damper position.
If the unit is equipped with an outdoor airflow station, the follow
-
ing points in
Configuration
ECON
CFM.C
need to be set.
If equipped with an outdoor airflow station, make sure
Config
-
uration
ECON
CFM.C
OCF.S
is enabled (set to 1 or 2).
If an outdoor airflow station is used, then the economizer will
control to cfm, not a position, as long as the sensor is valid.
Therefore,
Configuration
ECON
CFM.C
O.C.MX
su
-
persedes
Configuration
ECON
EC.MN
. Without cfm or
enthalpy control, the outdoor-air dampers will open to mini
-
mum position when the supply fan is running. Outdoor-air
dampers will spring-return closed upon loss of power or shut
-
down of the supply fan.
Indoor Air Quality Configurations
DEMAND CONTROLLED VENTILATION
Under
Configuration
IAQ
DCV.C
, the following configu
-
ration parameters should be set to establish the minimum and
maximum points for outdoor air damper position during de
-
mand controlled ventilation (DCV):
EC.MN
Economizer Min.Position
IAQ.M
IAQ Demand Vent Min.Pos.
O.C.MX
Economizer Min. Flow
O.C.MN
IAQ Demand Vent Min. Flow
Configuration
IAQ
DCV.C
IAQ.M
is used to set the ab
-
solute minimum vent position (or maximum reset) under DCV.
Configuration
IAQ
DCV.C
EC.MN
is used to set the
minimum damper position (or with no DCV reset). This is also
referenced in the economizer section.
Configuration
IAQ
DCV.C
O.C.MX
is used only with
the outdoor airflow station and will supersede
Configura
-
tion
IAQ
DCV.C
EC.MN
as long as the outdoor air cfm
sensor is valid.
Configuration
IAQ
DCV.C
O.C.MN
is used only with
the outdoor airflow station and will supersede
Configura
-
tion
IAQ
DCV.C
IAQ.M
as long as the outdoor air cfm
sensor is valid.
Exhaust Configurations
The following exhaust options should be configured.
Configuration
BP
BF.CF=1
Under
Configuration
BP
the following configurations may
be adjusted:
Under
Configuration
BP
B.V.A
the following configura
-
tions may be adjusted:
BP.FS
VFD/Act. Fire Speed
BP.MN
VFD/Act. Min. Speed
BP.MX
VFD Maximum Speed
Configuration
BP
BP.CF=2 (Return Fan Tracking Control)
Under
Configuration
BP
the following configurations may
be adjusted:
BP.SP
Building Pressure Setpoint (see note below)
Under
Configuration
BP
B.V.A
the following configura
-
tions may be adjusted:
BP.FS
VFD/Act. Fire Speed
BP.MN
VFD/Act. Min. Speed
BP.MX
VFD Maximum Speed
Under
Configuration
BP
FAN.T
the following configura
-
tions may be adjusted:
FT.CF
Fan Track Learn Enable (see note below)
FT.TM
Fan Track Learn Rate (see note below, not used
when Fan Track Learning is disabled)
FT.ST
Fan Track Initial DCFM
FT.MX
Fan Track Max Clamp (see note below, not used
when Fan Track Learning is disabled)
FT.AD
Fan Track Max Correction (see note below, not
used when Fan Track Learning is disabled)
FT.OF
Fan Track Internal EEPROM (see note below, not
used when Fan Track Learning is disabled)
FT.RM
Fan Track Internal Ram (see note below, not used
when Fan Track Learning is disabled)
FT.RS
Fan Track Reset Internal (see note below, not used
when Fan Track Learning is disabled)
NOTE: These configurations are used only if Fan Track Learning
is enabled. When Fan Track Learning is enabled, the control will
add an offset to the Fan Track Initial DCFM (
Configura
-
tion
BP
FAN.T
FT.ST
) if the building pressure deviates
from the Building Pressure Set Point (
BP.SP
). Periodically, at the
rate set by the Fan Track Learn Rate (
FT.TM
) the delta cfm is ad
-
justed upward or downward with a maximum adjustment at a giv
-
en instance to be no greater than Fan Track Max correction
(
FT.AD
). The delta cfm cannot ever be adjusted greater than or
less than the Fan Track Max Clamp (
FT.MX
).
Configuration
ECON
EC.MN
should always be set for the
minimum damper position.
If the unit is equipped with an outdoor airflow station, the follow
-
ing points in
Configuration
ECON
CFM.C
need to be set.
If equipped with an outdoor airflow station, make sure
Config
-
uration
ECON
CFM.C
OCF.S
is enabled (set to 1 or 2).
If an outdoor airflow station is used, then the economizer will
control to cfm, not a position, as long as the sensor is valid.
Therefore,
Configuration
ECON
CFM.C
O.C.MX
su
-
persedes
Configuration
ECON
EC.MN
. Without cfm or
enthalpy control, the outdoor-air dampers will open to mini
-
mum position when the supply fan is running. Outdoor-air
dampers will spring-return closed upon loss of power or shut
-
down of the supply fan.
Set Clock on VFD
The clock set mode is used for setting the date and time for the
internal clock of the VFD. In order to use the timer functions of
the VFD control, the internal clock must be set. The date is
used to determine weekdays and is visible in the fault logs. Re
-
fer to the VFD section in Appendix D on page 230 for informa
-
tion on operating the VFD and using the keypad.
To set the clock, perform the following procedure from the
VFD keypad:
1. Select MENU (SOFT KEY 2). The Main menu will display.
2. Use the UP or DOWN keys to highlight TIME AND DATE
SET on the display screen and press ENTER (SOFT KEY 2).
The clock set parameter list will be displayed.
3. Use the UP or DOWN keys to highlight CLOCK VISI
-
BILITY and press SEL (SOFT KEY 2). This parameter is
used to display or hide the clock on the screen. Use the UP
or DOWN keys to change the parameter setting. Press OK
(SOFT KEY 2) to save the configuration and return to the
Clock Set menu.
4. Use the UP or DOWN keys to highlight SET TIME and
press SEL (SOFT KEY 2). Use the UP or DOWN keys to
change the hours and minutes. Press OK (SOFT KEY 2) to
save the configuration and return to the Clock Set menu.
5. Use the UP or DOWN keys to highlight TIME FORMAT and
press SEL (SOFT KEY 2). Use the UP or DOWN keys to
change the parameter setting. Press OK (SOFT KEY 2) to
save the configuration and return to the Clock Set menu.
BP.SP
Building Pressure Set Point
BP.SO
BP Set Point Offset
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 ...