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Table 121 — VFD Terminal Designations
POWER EXHAUST — The units can be equipped with an
optional power exhaust system. The power exhaust fans are
forward-curved fans with direct-drive motors. The motors are
controlled directly by the
Comfort
Link™ controls through the
ECB1 board. On the 48/50A020-050 units there are 4 fans. On
the 48/50A051 and 060 units there are 6 fans. The fan sequenc-
es are controlled to provide 4 stages on the 48/50A020-050
units and 6 stages on the 48/50A051 and 060 units. There are
two control methods. For CV applications the fans can be
configured for 2 stages based on adjustable economizer
damper positions. For VAV applications and CV units with the
building pressure control option, the fans are sequenced to
maintain a building pressure set point based on a building
pressure transducer.
ECONOMIZER MOTOR — The economizer outside air and
return air dampers are gear-driven dampers without linkage. A
digitally controlled economizer motor controls their position.
The motor position is controlled by the ECB1 board by means
of a digital two-way communication signal. This allows for
accurate control of the motors as well as feedback information
and diagnostics information. The control has a self-calibration
routine that allows the motor position to be configured at initial
unit start-up. The motor is located on the economizer and can
be reached through the filter access door.
THERMISTORS AND PRESSURE TRANSDUCERS —
The 48/50AJ,AK,AW,AY units are equipped with thermistors
and pressure transducers. These units have two thermistors
connected to the condenser coil and two pressure transducers
that are connected to the low side of the system.
The 48/50A2,A3,A4,A5 units are equipped with four pres-
sure transducers. These units have two pressure transducers
connected to the low side of the system and two pressure trans-
ducers connected to the high side of the system.
By using either temperature sensors or transducers, the
Comfort
Link controller displays the high and low side pres-
sures and saturation temperatures. A normal gage set is not
required.
SMOKE DETECTOR — The units can be equipped with an
optional smoke detector located in the return air. The detector
is wired to the
Comfort
Link controls and, if activated, will stop
the unit by means of a special fire mode. The smoke detector
can also be wired to an external alarm system through TB5
terminals 10 and 11. The sensor is located in the return air sec-
tion behind the filter access door.
FILTER STATUS SWITCH — The units can be equipped
with an optional filter status switch. The switch measures the
pressure drop across the filters and closes when an adjustable
pressure set point is exceeded. The sensor is located in the
return air section behind the filter access door.
RETURN AIR CO
2
SENSOR
—
The unit can also be
equipped with a return air IAQ CO
2
sensor that is used for the
demand control ventilation. The sensor is located in the return
air section and can be accessed from the filter access door.
Fig. 31 — VFD Wiring
+
–
A48-7709
TERMINAL
FUNCTION
U1
V1
W1
Three-Phase Main Circuit Input Power Supply
U2
V2
Three-Phase AC Output to Motor, 0 V to
W2
Maximum Input Voltage Level
X1-11 (GND)
X1-12 (COMMON)
Factory-supplied jumper
X1-10 (24 VDC)
X1-13 (DI-1)
Run (factory-supplied jumper)
X1-10 (24 VDC)
Start Enable 1 (factory-supplied jumper). When
X1-16 (DI-4)
opened the drive goes to emergency stop.
X1-2 (AI-1)
X1-3 (AGND)
Factory wired for 4 to 20 mA remote input
Содержание WEATHERMAKER 48/50AJ
Страница 103: ...103 Fig 15 Typical Main Control Box Wiring Schematic 48 50AJ AK AW AY Units cont a48 8355 ...
Страница 104: ...104 Fig 16 Typical Main Control Box Wiring Schematic 48 50A2 A3 A4 A5 Units a48 8355 ...
Страница 105: ...105 TO NEXT PAGE Fig 17 Typical Auxiliary Control Box Wiring Schematic A48 7294 ...
Страница 106: ...106 Fig 17 Typical Auxiliary Control Box Wiring Schematic cont a48 8356 ...
Страница 107: ...107 Fig 18 Typical 2 Stage Gas Heat Wiring Schematic Size 051 and 060 Units Shown a48 8357 ...
Страница 108: ...108 TO NEXT PAGE Fig 19 Typical Staged Gas Heat Wiring Schematic Size 051 and 060 Units Shown A48 7296 ...
Страница 109: ...109 Fig 19 Typical Staged Gas Heat Wiring Schematic Size 051 and 060 Units Shown cont A48 8358 ...
Страница 110: ...110 Fig 20 Typical Electric Heat Control Schematic 50 Series Size 051 and 060 Units Shown a50 8228 ...
Страница 111: ...111 TO NEXT PAGE Fig 21 Typical Power Schematic 48 50AJ AK AW AY051 and 060 Units Shown A48 7298 ...
Страница 112: ...112 FROM PREVIOUS PAGE Fig 21 Typical Power Schematic 48 50AJ AK AW AY051 and 060 Units Shown cont a48 8360 ...
Страница 113: ...113 Fig 22 Typical Power Schematic 48 50A2 A3 A4 A5060 Unit Shown ...
Страница 114: ...114 SW1 SW2 OR DEHUMIDIFY SWITCH Fig 23 Typical Controls Option Wiring Schematic a48 8361 ...
Страница 115: ...115 Fig 24 Typical Small Chassis Component Location Size 020 035 Units a48 8362 ...
Страница 116: ...116 Fig 25 Typical Large Chassis Component Locations Size 036 060 Units A48 7302 ...
Страница 169: ...169 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...