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APPENDIX F — OPTIONAL FACTORY-INSTALLED LOW AMBIENT MOTORMASTER
®
V CONTROL (cont)
Configure Motormaster
®
V Control
The Motormaster V control is configured for proportional inte-
gral (PI) control mode. The Motormaster V control varies the
condenser fan motor speed to maintain a setpoint of liquid line
head pressure. See Table L. Note that the pressure transducer
must be attached for proper configuration.
Table L — Configuration Table
The following
Comfort
Link control configurations must be set
when using a Motormaster V device:
•
Configuration
COOL
M.M.
= YES
Test Motormaster V Control
To test the control and motor in the test mode, run compressor
no. 1. The Motormaster V electronic control adjusts the fan
speed based on the liquid line pressure input. Ensure that fans
are rotating clockwise (as viewed from above). If rotation is
backward, lock out all power then swap 2 leads AFTER the
Motormaster V control.
For 48/50A2,A3,A4,A5 units, fan stages react to discharge
pressure transducers (DPT) (
Pressures
REF.P
DP.A
and
DP.B
) which are connected to the compressor discharge piping
in circuit A and B. The control converts the pressures to the
corresponding saturated condensing temperatures (
Tempera-
tures
REF.T
SCT.A
and
SCT.B
).
Fig. P — Low Ambient MMV Control Location — 48/50A060 MCHX Units
NOMINAL
VOLTAGE
(V-Ph-Hz)
MODE
CONTROL
INPUTS
(Pin 5)
START CONTACTS
230-3-60
1
4 to 20mA
TB1,2
460-3-60
575-3-60
208-3-60
2
TB13A,2
380-3-60
400-3-50
4
TB 13C,2
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 ...