Lennox CBA27UHE-018, Руководство пользователя

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Page 8
C-Transformer (T1)
CBA27UHE series units use a single line voltage to
24VAC transformer mounted in the control box. The
transformer supplies power to the control circuits in the
indoor and outdoor unit. Transformers are rated at 70VA.
208/240VAC single phase transformers use two primary volt­
age taps as shown in figure 3.
FIGURE 3
BLUE
YELLOW
ORANGE
RED
BLACK
240 VOLTS
208 VOLTS
PRIMARY
SECONDARY
208 / 240 VOLT TRANSFORMER
F1
D- Fuse (F1)
All transformers used in the CBA27UHE series units have a
fuse (F1) wired in series on the low secondary side. See fig­
ure 3. F1 provides secondary voltage overcurrent protec­
tion and is rated at 3 amps.
E-Blower Relay (K20)
CBA27UHE units use a DPDT relay to energize the blow­
er motor during a call for
electric heat only. When the
relay coil is energized on an electric heat call, a set of
N.O. contacts closes to energize the blower motor on
heating speed.
F-Dehumidification Relay (K183)
Relay K183 is used for dehumidification during cooling
demand. K183 decreases blower speed resulting in an
increase in the amount of moisture taken from the air.
See wiring diagram on page Page 44 and operation se­
quence on Page 44 for more detail.
BLOWER ASSEMBLY
FIGURE 4
Motor Terminals
G-Blower Motor (B3)
IMPORTANT
Blower motor features programmed electronic
braking. The integral control brakes the motor
near the end of the supply air blower operation,
allowing the motor to maintain a more controlled
ramping shut-down. Each blower is statically and
dynamically balanced as an assembly before
installation in the unit.