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36
Enable Digital Scroll (DS.EN)
This configuration instructs the unit controls as to whether a
digital scroll compressor is installed. If set to YES, the com-
pressor will be controlled by the compressor staging routine
and SUMZ Cooling Algorithm. The digital scroll compressor
location will be based on unit size according to the following
table:
DS Min Digital Capacity (DS.MC)
This configuration defines the minimum capacity the digital
scroll compressor is allowed to modulate to. The digital scroll
compressor modulation 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 capacity reduction adjustments when OAT is
greater than
Configuration
COOL
DS.RO
. This ramped
reduction is only imposed on a decrease in digital scroll capac-
ity. An increase in capacity will continue to follow the value
defined by
Configuration
COOL
DS.AD
.
Digital Scroll Reduction OAT (DS.RO)
Under certain operating conditions, a sharp decrease in digital
scroll capacity can result in unstable unit operation. This con-
figuration defines the outdoor-air temperature above which a
reduced capacity (
Configuration
COOL
DS.RP
) and
time delay (
Configuration
COOL
DS.RD
) will be im-
posed on a digital scroll capacity reduction. This ramped re-
duction is only imposed on a decrease in digital scroll capacity.
An increase in capacity will continue to follow the values de-
fined by
Configuration
COOL
DS.AP
and
Configura-
tion
COOL
DS.AD
.
Digital Scroll Max Only OAT (DS.MO)
This configuration defines the outdoor-air temperature above
which the digital 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 staging and maintaining head
pressure control. This configuration will have a range of 80 to
150°F and have a default of 110°F.
Motormaster Control (M.M.)
The Motormaster control configuration (M.M.) Units with fac-
tory installed Motormaster V speed control option, this config-
uration must be set to YES. See “HEAD PRESSURE CON-
TROL” on page 46 and Appendix F 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.
Motormaster Setpoint Offset (MM.OF)
This value is added to HPSP in order to calculate the Motor-
master setpoint MM_SP. This value will 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 Motor-
master
Comfort
Link PD routine. This value will have a range
of 10 to 120 and a default of 10.
Motormaster Proportional Gain (MM.PG)
This is the proportional gain for the Motormaster control PD
control loop. This value will have a range of 0.0 to 5 and a de-
fault of 1.
Motormaster Derivative Gain (MM.DG)
This is the derivative gain for the Motormaster control PD control
loop. This value will have a range of 0 to 5 and a default of 0.3.
Motormaster Integration Time (MM.TI)
This is the integration time constant for the Motormaster con-
trol PD control loop. This values will have a range of 0 to 50
and default of 30.
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.
CSB B1 Feedback Alarm (CS.B1)
This configuration is used to enable or disable the compressor
B1 feedback alarm. This configuration must be enabled at all
times.
CSB B2 Feedback Alarm (CS.B2)
This configuration is used to enable or disable the compressor
B2 feedback alarm. This configuration must be enabled at all
times.
Reverse Rotation Verified? (REV.R)
If this configuration is set to NO, then after a power up, in the
normal run mode, the control will check the suction pressure on
the first circuit that is energized after 5 seconds of run time. If
the control does not see a sufficient decrease in suction pressure
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 WEATHERMAKER 48A2020
Page 112: ...112 Fig 20 Typical Main Control Box Wiring Schematic 48 50A Units ...
Page 113: ...113 Fig 21 Typical Auxiliary Control Box Wiring Schematic ...
Page 114: ...114 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown ...
Page 115: ...115 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown TO NEXT PAGE ...
Page 116: ...116 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont ...
Page 117: ...117 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown ...
Page 118: ...118 Fig 25 Typical Controls Option Wiring Schematic SW1 SW2 OR DEHUMIDIFY SWITCH ...
Page 119: ...119 Fig 26 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown ...
Page 120: ...120 Fig 27 Typical Power Schematic of Greenspeed Low Ambient Option 48 50A 060 Unit Shown ...
Page 121: ...121 Fig 28 Typical Small Chassis Component Location Size 020 035 Units ...
Page 122: ...122 Fig 29 Typical Large Chassis Component Locations Size 040 060 Units ...
Page 185: ...185 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...