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155
Table 97 —
Staged Gas Control Board (SCB) Inputs and Outputs
Table 98 —
Control Expansion Module (CEM) Inputs and Outputs
COMPRESSOR EXPANSION BOARD (CXB)
The CXB is used to provide additional compressor outputs and
CSB inputs. See Table 99.
EXPANSION VALVE CONTROL BOARD (EXV)
The EXV is used on all units to control the EXVs. The EXV
board is also used on Humidi-MiZer
®
equipped units to pro
-
vide control of the condenser and bypass modulating valves.
See Tables 100-102.
LOW VOLTAGE TERMINAL STRIP
This circuit board provides a connection point between the ma
-
jor control boards and a majority of the field-installed accesso
-
ries. See Table 103. The circuit breakers for the low voltage con
-
trol transformers, interface connection for the Carrier Comfort
Network
®
(CCN) communication, and interface connection for
the Local Equipment Network (LEN) communication are also
located on the low voltage terminal strip.
INTEGRATED GAS CONTROL (IGC)
One IGC is provided with each bank of gas heat exchangers.
The quantity of IGC boards will range from 2 to 5 depending
on the size of the unit and whether the unit is low, medium or
high heat. The IGC controls the direct spark ignition system
and monitors the rollout switch, limit switches, and induced-
draft motor Hall Effect switch.
For units equipped with modulating gas heat, the IGC in the
modulating gas section uses a pressure switch in place of the
Hall Effect sensor. The IGC is equipped with a LED (light-
emitting diode) for diagnostics. See Table 104.
POINT NAME
POINT DESCRIPTION
TYPE OF I/O
I/O POINT NAME CONTROL BOARD CONNECTOR
PIN NO.
INPUTS
LIMSWTMP
Staged Gas Limit Sw. Temp
Thermistor / Transducer (0-5V)
AN1
SCB
J5, 1-3
LAT1SGAS
Staged Gas LAT 1
Thermistor / Transducer (0-5V)
AN2
SCB
J5, 4-6
LAT2SGAS
Staged Gas LAT 2
Thermistor / Transducer (0-5V)
AN3
SCB
J5, 7-9
LAT3SGAS
Staged Gas LAT 3
Thermistor / Transducer (0-5V)
AN4
SCB
J5, 10-12
Not Used
Not Used
Thermistor / Transducer (0-5V)
AN5
SCB
J5, 13-15
LP_A
Circuit A Liquid Pressure Transducer Thermistor / Transducer (0-5V)
AN6
SCB
J6, 1-3
LP_B
Circuit B Liquid Pressure Transducer Thermistor / Transducer (0-5V)
AN7
SCB
J6, 4-6
Not Used
Not Used
Thermistor / Transducer (0-5V)
AN8
SCB
J6, 7-9
Not Used
Not Used
Thermistor
AN9
SCB
J7, 1-2
Not Used
Not Used
Thermistor
AN10
SCB
J7, 3-4
OUTPUTS
HTMG_CAP
Modulating Gas Capacity
4-20mA
AO1
SCB
J8, 1-2
Not Used
Not Used
4-20mA
AO2
SCB
J8, 3-4
HS3
Relay 3 W1 Gas Valve 2
Relay
RLY1
SCB
J9, 1-3
HS4
Relay 4 W2 Gas Valve 2
Relay
RLY2
SCB
J9, 4-6
HS5
Relay 5 W1 Gas Valve 3
Relay
RLY3
SCB
J9, 7-9
HS6
Relay 6 W2 Gas Valve 3
Relay
RLY4
SCB
J9, 10-12
POINT NAME
POINT DESCRIPTION
TYPE OF I/O I/O POINT NAME CONTROL BOARD CONNECTOR
PIN NO.
INPUTS
DHDISCIN
Dehumidify Switch Input
Switch
DI1
CEM
J7, 1-2
DMD_SW1
Demand Limit Switch 1
Switch
DI2
CEM
J7, 3-4
DMD_SW2
Demand Limit Switch 2
Switch
DI3
CEM
J7, 5-6
PRES
Pressurized Input
Switch
DI4
CEM
J7, 7-8
EVAC
Evacuation Input
Switch
DI5
CEM
J7, 9-10
PURG
Smoke Purge Input
Switch
DI6
CEM
J7, 11-12
IAQIN
IAQ - Discrete Input
Switch
DI7
CEM
J7, 13-14
MARH_MA
MARH milliamps
Transducer
(4-20mA)
AN7
CEM
J6, 1-3
OARH_MA
OARH milliamps
Transducer
(4-20mA)
AN8
CEM
J6, 4-6
SPRH_MA
SPRH milliamps
Transducer
(4-20mA)
AN9
CEM
J6, 7-9
RARH_MA
RARH milliamps
Transducer
(4-20mA)
AN10
CEM
J6, 10-12
DMDLMTMA
4-20 mA Demand Signal
Thermistor
AN1
CEM
J5, 1-2
SASPRSET
Supply Air Setpnt. Reset
Thermistor
AN2
CEM
J5, 3-4
OAQ_MA, SPRST_MA
OAQ milliamps, SP Reset milliamps
Thermistor
AN3
CEM
J5, 5-6
OACFM
Outside Air CFM
Thermistor
AN4
CEM
J5, 7-8
FLTS/FLT_PDT
Filter Status/Filter Pressure Drop Transducer
Thermistor
AN5
CEM
J5, 9-10
PFLTS, PFLT_PDT
Post Filter Status Input/Pressure Drop Transducer Thermistor
AN6
CEM
J5, 11-12
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 ...