163
Table 109 —
Thermistors and Unit Operation Control Pressure Transducers
LEGEND
SPACE CO
2
SENSORS
The
Comfort
Link controls also support a CO
2
IAQ sensor that
can be located in the space for use in demand controlled venti
-
lation. The sensor must be a 4 to 20 mA sensor and should be
connected to TB201 terminals 7 and 8.
ECONOMIZER HUMIDITY CHANGEOVER SENSORS
• The
Comfort
Link controls support 5 different changeover
systems for the economizer. These are:
• Outdoor enthalpy switch
• Outdoor air dry bulb
• Differential dry bulb
• Outdoor air enthalpy curves
• Differential enthalpy
• Custom curves (a combination of an enthalpy/dew point
curve and a dry bulb curve).
The units are equipped as standard with an outdoor air enthalpy
control. Outside air and return air dry bulb sensors, which sup
-
port the dry bulb changeover method, are also supplied as stan
-
dard. If the other methods are to be used, then a field-installed
humidity sensor must be installed for outdoor air enthalpy and
customer curve control and 2 humidity sensors must be in
-
stalled for differential enthalpy. Installation holes are pre-
drilled and wire harnesses are installed in every unit for con
-
nection of the humidity sensors. The
Comfort
Link controls
have the capability to convert the measured humidity and dry
bulb temperature into enthalpy.
SENSOR
DESCRIPTION AND LOCATION
PART NO.
Thermistors
CCT
Cooling Coil Thermistor input. Provided with factory-option hydronic heat. Located on face of the hydronic
heating coil. Consists of 4 thermistors wired into a 2x2 array.
HH79NZ039 (4)
LST
Limit Switch Thermistor. Provided with Staged Gas Control option. Located in the heating compartment. HH79NZ034
OAT
Outside Air Thermistor. Located in the condenser section on the back side of the power box.
HH79NZ039
RAT
Return Air Thermistor.
Without Economizer: Located on left side base rail in the return plenum.
With Economizer: Located on left side face of return damper section in the return plenum.
HH79NZ039
SAT
Supply Air Thermistor. Located in the Supply Fan section, on left side of the fan housing. (May be
relocated or replaced when unit is used with CCN Linkage systems; see page 71.)
HH79NZ039
LAT 1,2,3
Leaving Air Thermistors, provided with Staged Heat Control option. Shipped in the control box. Installer
must pull out and mount in the supply duct.
HH79NZ034 (3)
ST-A1
ST-A2
Suction Thermistor, Circuits A1 and A2. Located in well in evaporator outlet. A1 is top coil, A2 is bottom
coil
HH79NZ014 (2)
ST-B1
ST-B2
Suction Thermistor, Circuits B1 and B2. Located in well in evaporator outlet. B1 is top coil, B2 is bottom
coil
HH79NZ014 (2)
LT_A
Liquid Line Thermistor, Circuit A. Located in evaporator section on inlet to EXV A1 and A2.
HH79EZ003
LT_B
Liquid Line Thermistor, Circuit B. Located in evaporator section on inlet to EXV B1 and B2.
HH79EZ003
Control Pressure Transducers
BP
Building Pressure. Provided with Power Exhaust and Return Fan options. Located in the control box.
HK05ZG022
DPT-A
Discharge Pressure (refrigerant), Circuit A.
HK05ZZ001
DPT-B
Discharge Pressure (refrigerant), Circuit B.
HK05ZZ001
SPT-A
Suction Pressure (refrigerant), Circuit A.
HK05SZ003
SPT-B
Suction Pressure (refrigerant), Circuit B.
HK05SZ003
DP
Duct Static Pressure. Provided with VAV models equipped with VFD options. Located in the control box. HK05ZG010
SACFM
Supply Air Cfm (velocity pressure). Provided with factory-option return fan system
(75-100 ton only). Located in the control box.
HK05ZG015
RACFM
Return Air Cfm (velocity pressure). Provided with factory-option return fan system
(75-100 ton only). Located in control box.
HK05ZG07
OACFM
Outside Air Cfm Monitor (velocity pressure). Provided with the Outside Air Cfm Control option. Located in
control box.
48NG501985 (75-105)
48NG501986 (120-150)
DTT
Digital Scroll Discharge Temperature Thermistor. Provided with digital scroll compressor option. Located
on discharge line.
HH79EZ003
RGTA
Circuit A Return Gas Thermistor. Provided with MLV option. Located in suction line well.
HH79NZ014
FT_SF SACFM
Supply Air CFM - Sensor bars are mounted on inlet to fan. Transducer is mounted in Control Box and is
fan dependent.
HK05ZG019 (Low Fan)
HK05ZG023 (High Fan)
FT_PE EACFM
Power Exhaust CFM - Sensor bars are mounted on inlet to fan. Transducer is mounted in Control Box
and is fan dependent.
HK05ZG019 (Low Fan)
HK05ZG023 (High Fan)
FT_RF RACFM
Return Air CFM - Sensor bars are mounted on inlet to fan. Transducer is mounted in Control Box and is
fan dependent.
HK05ZG020 (Low Fan)
HK05ZG023 (High Fan)
OACFM
Outside Air CFM - Sensor bars are mounted on air intake, same side as Control Box. Transducer is
mounted in Control Box and is Unit size dependent.
48NG501985 (75 - 105)
48NG501986 (120 - 150)
MFDP
Filter Pressure Sensor - Return (+24 VDC, 4 20 mA loop power). Transducer is mounted in Control Box. HK05ZG019
PFDP
Filter Pressure Sensor - Return (+24 VDC, 4 20 mA loop power). Transducer is mounted in Control Box. HK06WC035
CCN
—
Carrier Comfort Network
EXV
—
Expansion Valve Control Board
MLV
—
Minimum Load Hot Gas Bypass Valve
VAV
—
Variable Air Volume
VFD
—
Variable Frequency Drive
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 ...