Carrier Weathermaster 48P2030-100, Controls, Start-Up, Operation, Service, And Troubleshooting

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VFD2 Acceleration Time (ACCL)
This configuration sets the acceleration time from zero to max-
imum output frequency. Power to the VFD must be cycled in
order for a change to this configuration to take effect.
VFD2 Deceleration Time (DECL)
This configuration sets the deceleration time from maximum
output frequency to zero. Power to the VFD must be cycled in
order for a change to this configuration to take effect.
VFD2 Switching Frequency (SW.FQ)
This configuration sets the switching frequency for the drive.
Power to the VFD must be cycled in order for a change to this
configuration to take effect.
VFD2 Type (TYPE)
This configuration sets the type of VFD communication. This
configuration should not be changed without first consulting a
Carrier service engineering representative.
Remote Control Switch Input
The remote switch input is located on the RXB board and con-
nected to TB201 terminals 3 and 4. The switch can be used for
several remote control functions. See Table 81.
Table 81 — Remote Switch Configuration
Remote Input State (Inputs

GEN.I

REMT)
This is the actual real time state of the remote input.
Remote Switch Config (Configuration

UNIT

RM.CF)
This is the configuration that allows the user to assign different
types of functionality to the remote discrete input.
• 0 — NO REMOTE SW — Remote switch will not be used.
• 1 — OCC-UNOCC SW — The remote switch input will con-
trol the occupancy state. When the remote switch input is ON,
the unit is forced into the occupied mode. When the remote
switch is OFF, the unit is forced into the unoccupied mode.
• 2 — STRT/STOP — The remote switch input will start
and stop the unit. When the unit is commanded to stop, any
timeguards in place on compressors will be honored first.
When the remote switch is ON, the unit will be command-
ed to stop. When the remote switch is OFF, the unit will be
enabled to operate.
• 3 — OVERRIDE SW — The remote switch can be used to
override any internal or external time schedule being used
by the control and force the unit into an occupied mode
when the remote input state is ON. When the remote
switch is ON, the unit will be forced into an occupied state.
When the remote switch is OFF, the unit will use its inter-
nal or external time schedules.
Remote Switch Logic Configuration (Configuration

SW.LG

RMI.L)
The control allows for the configuration of a normally open/
closed status of the remote input switch via RMI.L. If this
variable is configured OPEN, then when the switch is open,
the remote input switch perceives the logic state as OFF. Cor-
respondingly, if RMI.L is set to CLOSED, the remote input
switch will perceive a closed switch as meaning OFF. See
Table 82.
Hot Gas Bypass
The Comfort Link control system supports the use of an option-
al minimum load hot gas bypass valve (MLV) that is directly
controlled by the Comfort Link control system. This provides
an additional stage of capacity as well as low load coil freeze
protection. Hot gas bypass is an active part of the P-Series
Comfort Link capacity staging and minimum evaporator load
protection functions. It is controlled through the Minimum
Load Valve function. The hot gas bypass option consists of a
solenoid valve with a fixed orifice sized to provide a nominal
3-ton evaporator load bypass. A hot gas refrigerant line routes
the bypassed hot gas from the discharge line of circuit A to the
suction line of circuit A. An additional thermistor in the suc-
tion line allows the unit control to monitor suction superheat.
When the unit control calls for hot gas bypass, the hot gas by-
passes the evaporator and adds refrigeration load to the com-
pressor circuit to reduce the cooling effect from Circuit A.
The hot gas bypass system is a factory-installed option in-
stalled on Circuit A only. This function is enabled at Configu-
ration

COOL

MLV . When this function is enabled, an ad-
ditional stage of cooling capacity is provided by the unit con-
trol staging sequences (see Appendix C).
Space Temperature Offset
Space Temperature Offset corresponds to a slider on a T56 sen-
sor that allows the occupant to adjust the space temperature by
a configured range during an occupied period. This sensor is
only applicable to units that are configured as Multi-Stage SPT
control ( Configuration

UNIT

C.TYP = 4).
Space Temperature Offset Sensor (Configuration

UNIT

SENS

SP.O.S)
This configuration disables the reading of the offset slider.
Space Temperature Offset Range (Configuration

UNIT

SENS

SP.O.R)
This configuration establishes the range, in degrees F, that the
T56 slider can affect SPTO when adjusting the slider from the
far left ( - SP.O.R ) to the far right (+ SP.O.R ). The default is 5°F.
Space Temperature Offset Value (Temperatures

AIR.T

SPTO)
The Space Temperature Offset Value is the reading of the slider
potentiometer in the T56 that is resolved to delta degrees based
on SP.O.R .
Table 82 — Remote Switch Logic Configuration
ITEM EXPANSION RANGE UNITS
CCN
POINT
REMT Remote Input State ON/OFF RMTIN
RM.CF Remote Switch Config 0 to 3 RMTINCFG
RMI.L RemSw
Off-Unoc-Strt-NoOv Open/Close RMTINLOG
ITEM EXPANSION RANGE UNITS
CCN
POINT
SP.O.S Space Temp
Offset Sensor Enable/
Disable SPTOSENS
SP.O.R Space Temp
Offset Range 1 to 10 SPTO_RNG
SPTO Space Temperature
Offset +- S P.O.R ^F SPTO
REMOTE
SWITCH LOGIC
CONFIGURATION
(RMI.L)
SWITCH
STATUS REMOTE INPUT STATE
(REMT)
REMOTE SWITCH CONFIGURATION (RM.CF)
0 1 2 3
No Remote Switch Occ-Unocc Switch Start/Stop Override
OPEN
OPEN OFF (0) xxxxx Unoccupied Start No Override
CLOSED ON (1) xxxxx Occupied Stop Override
CLOSED
OPEN ON (0) xxxxx Occupied Stop Override
CLOSED OFF (1) xxxxx Unoccupied Start No Override