34
Compressor Lockout Temperature (
MC.LO
) — This config-
uration is the outdoor air temperature setting below which
mechanical cooling is locked out.
Fan-Off Delay, Mech Cool (
C.FOD
) — After a mechanical
cooling cycle has ended, this is the delay in seconds that the
supply fan will continue to operate.
Min. Load Valve (HGBP)? (
MLV
) — This configuration in-
structs the control as to whether a minimum load valve has
been installed and will be controlled by the compressor staging
routine.
NOTE: If the unit is configured for a Digital Scroll (
Configu-
ration
COOL
DS.EN = YES
) or Minimum Load Valve
(
Configuration
COOL
MLV = ENABLE
), then circuit A
is always the lead circuit regardless of the setting of this con-
figuration. This configuration must be set to 1 (CIRCUIT A)
for size 30 to 60 units if an accessory low ambient operation
Motormaster
®
V control is installed on the unit. If the unit is
configured for the Humidi-MiZer
®
adaptive dehumidification
system, then circuit B automatically becomes the lead circuit
when the unit enters into one of the Humidi-MiZer modes
(dehumidification or reheat). The unit will immediately start a
circuit B compressor when a Humidi-MiZer mode is initiated.
Motormaster Control? (
M.M
.
) — The low ambient Motormas-
ter control configuration (M.M.) units with accessory Motor-
master V speed control option installed from the factory, this
configuration must be set to YES. See Head Pressure Control
section, page 43 for more information.
NOTE: The non-factory-installed Motormaster V speed con-
trol accessory is a completely self-contained device and is not
managed by the unit's
Comfort
Link controller.
Head Pressure Setpoint (
HPSP
) — This is the head pressure
setpoint used by the
Comfort
Link control during condenser fan,
head pressure control. This configuration shall have a range of
80 to 150 F and have a default of 110.
Compressor Lockout Temperature (
MC.LO
) — This config-
uration defines the outdoor air temperature below which me-
chanical cooling is locked out. To make proper use of Motor-
master control, it shall be necessary for an operator to manually
change this setting. This configuration shall have a range of
–20 to 55 F and have a default of 40.
Motormaster Setpoint Offset (
MM.OF
) — This value is add-
ed to HPSP in order to calculate the Motormaster setpoint
MM_SP. This value shall have a range of –20 to 20 and a
default of –10.
Motormaster PD Run Rate (
MM.RR
) — This is the number
of seconds between execution of the Motormaster
Comfort
Link
PD routine. This value shall have a range of 10 to 120 and a de-
fault of 10.
Motormaster Proportional Gain (
MM.PG
) — This is the pro-
portional gain for the Motormaster control PD control loop.
This value shall have a range of 0.0 to 5 and a default of 1.
Motormaster Derivative Gain (
MM.DG
) — This is the deriv-
ative gain for the Motormaster control PD control loop. This
value shall have a range of 0 to 5 and a default of 0.3.
Motormaster Integration Time (
MM.TI
) — This is the inte-
gration time constant for the Motormaster control PD control
loop. This values shall have a range of 0 to 50 and default of 30.
Enable Digital Scroll (
DS.EN
) — This configuration in-
structs the unit controls as to whether a digital scroll compres-
sor is installed. If set to YES, the compressor will be controlled
by the compressor staging routine and SUMZ Cooling
Algorithm. The digital scroll compressor location shall be
based on unit size according to the following table:
DS Min Digital Capacity (
DS.MC
) — This configuration de-
fines the minimum capacity the digital scroll compressor is al-
lowed to modulate to. The digital scroll compressor modula-
tion range will be limited from
DS.MC
to 100%.
Digital Scroll Adjust Delta (
DS.AP
) — This configuration
defines the maximum capacity the digital scroll will be allowed
to change per request by the SUMZ Cooling Algorithm.
Digital Scroll Adjust Delay (
DS.AD
) — This configuration
defines the time delay in seconds between digital scroll
capacity adjustments.
Digital Scroll Reduce Delta (
DS.RP
) — This configuration
defines the maximum capacity the digital scroll will be allowed
to decrease per request by the SUMZ Cooling Algorithm when
OAT is greater than
Configuration
COOL
DS.RO
. This
ramped reduction is only imposed on a decrease in digital
scroll capacity. An increase in capacity will continue to follow
the value defined by
Configuration
COOL
DS.AP
.
Digital Scroll Reduce Delay (
DS.RD
) — This configuration
defines the time delay, in seconds, between digital scroll capac-
ity reduction adjustments when OAT is greater than
Configu-
ration
COOL
DS.RO
. This ramped reduction is only im-
posed on a decrease in digital scroll capacity. An increase in ca-
pacity will continue to follow the value defined by
Configuration
COOL
DS.AD
.
Digital Scroll Reduction OAT (
DS.RO
) — Under certain op-
erating conditions, a sharp decrease in digital scroll capacity
can result in unstable unit operation. This configuration defines
the outdoor-air temperature above which a reduced capacity
(
Configuration
COOL
DS.RP
) and time delay (
Configu-
ration
COOL
DS.RD
) will be imposed on a digital scroll
capacity reduction. This ramped reduction is only imposed on a
decrease in digital scroll capacity. An increase in capacity will
continue to follow the values defined by
Configuration
COOL
DS.AP
and
Configuration
COOL
DS.AD
.
Digital Scroll Max Only OAT (
DS.MO
) — This configura-
tion defines the outdoor-air temperature above which the digi-
tal scroll will not be allowed to modulate. The digital scroll will
be locked at 100% above this outdoor-air temperature.
Head Pressure Setpoint (
HPSP
) — This is the head pressure
setpoint used by the
Comfort
Link control during condenser
fan, head pressure control.
Enable Compressor A1 (
A1.EN
) — This configuration is
used to disable the A1 compressor in case of failure.
Enable Compressor A2 (
A2.EN
) — This configuration is
used to disable the A2 compressor in case of failure.
Enable Compressor B1 (
B1.EN
) — This configuration is
used to disable the B1 compressor in case of failure.
Enable Compressor B2 (
B2.EN
) — This configuration is
used to disable the B2 compressor in case of failure.
CSB A1 Feedback Alarm (
CS.A1
) — This configuration is
used to enable or disable the compressor A1 feedback alarm.
This configuration must be enabled at all times.
CSB A2 Feedback Alarm (
CS.A2
) — This configuration is
used to enable or disable the compressor A2 feedback alarm.
This configuration must be enabled at all times.
UNIT SIZE
DIGITAL SCROLL COMPRESSOR
20
B1
25
B1
27
B1
30
A1
35
A1
40
A1
50
A1
60
A1
Summary of Contents for Carrier Weathermaker 48A2
Page 105: ...105 Fig 20 Typical Main Control Box Wiring Schematic 48 50A2 A3 A4 A5 Units...
Page 106: ...106 Fig 21 Typical Auxiliary Control Box Wiring Schematic...
Page 107: ...107 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown a48 8357...
Page 108: ...108 TO NEXT PAGE Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown A48 7296...
Page 109: ...109 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont A48 8358...
Page 110: ...110 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown a50 8228...
Page 111: ...111 Fig 25 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown...
Page 112: ...112 Fig 26 Typical Low Ambient Controls Option Wiring...
Page 113: ...113 Fig 27 Typical Small Chassis Component Location Size 020 035 Units...
Page 114: ...114 Fig 28 Typical Large Chassis Component Locations Size 040 060 Units...
Page 118: ...118 Fig 30 Economizer Control Board ECB1 and VAV Control Board ECB2 A48 7706...
Page 142: ...142 A48 3733 Fig 56 Main Burner Removal...
Page 176: ...176 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716...
