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42
Unit Configuration
There is a submenu under the Configuration mode of the local
display entitled
UNIT
. This submenu contains an assortment of
items that most of which are relative to other particular sub-
sections of this control manual. This section will define all of
these configurations here for easy reference. The submenu
which contains these configurations is located at the local dis
-
play under
Configuration
UNIT
.
Machine Control Type (C.TYP)
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 types possible will now be defined:
•
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 contin
-
uously 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 unoccu
-
pied 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 per
-
form 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. Unlike traditional 2-stage space temperature con
-
trol, 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.
Unit Size (75-150) (SIZE)
There are several available tonnages for the N Series control.
Make sure this configuration matches the size called out by the
model number of the unit. This is important, as the cooling stage
tables are directly determined based on the SIZE configuration.
Fan Mode (FN.MD) (0= Auto, 1= Cont)
This Fan Mode configuration can be used for machine control
types (
Configuration
UNIT
C.TYP
) 3 and 4.
The Fan Mode variable establishes the operating sequence for
the supply fan during occupied periods. When set to 1 = Contin
-
uous, the fan will operate continuously during occupied periods.
When set to 0 = Automatic, the fan will run only during a heat
-
ing or cooling mode.
Remote Switch Configuration (RM.CF)
The remote switch input is connected to TB201 terminals 1 and
2. This switch can be used for several remote control functions.
Please refer to the Remote Control Switch Input section on
page 100 for details on its use and operation.
CEM Module Installed (CEM)
This configuration instructs the control to communicate with
the Controls Expansion Module (CEM) over the local equip
-
ment network (LEN) when set to YES. When the unit is con
-
figured for certain sensors and configs, this option will be set
to YES automatically. The sensors and configurations that au
-
tomatically turn on this board are:
Configuration
UNIT
SENS
SRH.S
= Enable (Space
Relative Humidity Sensor Enable)
Configuration
SP
SP.RS
= 1 (Static Pressure Reset using
4-20 mA sensor)
Configuration
UNIT
SENS
RRH.S
= Enable (Return
Air Relative Humidity Sensor Enable)
Configuration
UNIT
SENS
MRH.S
= Enable (Mixed
Air Relative Humidity Sensor Enable)
Configuration
SP
SP.RS
= 4 (Static Pressure Reset using
VFD Control)
Configuration
ECON
CFM.C
OCF.S
= Enable (set to 1
or 2) (Outdoor Air CFM Sensor Enable)
Configuration
EDT.R
RES.S
= Enable (4-20 mA Supply
Air Reset Sensor Enable)
Configuration
ECON
ORH.S
= Enable (Outside Air Rela
-
tive Humidity Sensor Enable)
Configuration
DEHU
D.SEN
= 3 (DISCR.INPUT) (De
-
humidification Sensor - Discrete Input Select)
Configuration
BP
DMD.L
DM.L.S
= 1 (2 SWITCHES)
(Demand Limiting using 2 discrete switches)
Configuration
BP
DMD.L
DM.L.S
= 2 (4-20MA CTRL)
(Demand Limiting using a 4-20 mA sensor)
Configuration
IAQ
AQ.CF
IQ.I.C
= 1 (IAQ DISCRETE)
(IAQ discrete switch control)
Configuration
IAQ
AQ.CF
IQ.I.C
= 2 (IAQ DISC.OVR)
(IAQ discrete switch “override” control)
Configuration
IAQ
AQ.CF
OQ.A.C
= 1 (OAQ SENS-
DAQ) (Outdoor Air Quality Sensor)
Configuration
IAQ
AQ.CF
OQ.A.C
= 2 (4-20 NO DAQ)
(4-20 mA sensor, no DAQ)
Configuration
IAQ
FLTC
MFL.S
= 1,3,4,5 (Main Filter
Status is not disabled or schedule)
Configuration
IAQ
FLTC
PFL.S
= 1,3,4,5 (Post Filter
Status is not disabled or schedule)
Liquid Sensors Installed (LQ.SN)
This configuration instructs the control to read the liquid tem
-
perature thermistors and pressure transducers on A and B re
-
frigeration circuits.
Power Monitor Installed (PW.MN)
This configuration instructs the control to monitor the power
status input.
VFD Bypass Enable (VFD.B)
This configuration instructs the control to enable the EXB in
order to use the supply fan relay (
SFBYRLY
) and ret/exh by
-
pass relay (
PEBRLY
) outputs. To make the equipment operate
with optional bypasses for the fans, first disable all static pres
-
sure fan control types (
SP.CF
,
SP.SV
and
SP.S
), then set
VFD.B
to enable.
Enable Smart Menu (SM.MN)
When enabled this configuration causes the control to only dis
-
play the points associated with the particular unit configura
-
tion. For example, if the unit does not have heat, the heating
points will not be displayed.
Temperature Compensated Start Cooling Factor (TCS.C)
This factor is used in the equation of the Temperature Compen
-
sated Start Time Bias for cooling. Refer to the Temperature
Compensated Start section for more information. A setting of 0
minutes indicates Temperature Compensated Start in Cooling
is not permitted.
Temperature Compensated Start Heating Factor (TCS.H)
This factor is used in the equation of the Temperature Compen
-
sated Start Time Bias for heating. Refer to the Temperature
Compensated Start section for more information. A setting of 0
minutes indicates Temperature Compensated Start in Heating
is not permitted.
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 ...