Trane SRUB, Установка, эксплуатация и обслуживание, Страница: 18 / 27

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SRUB-IOM001-EN
Electrical Wiring
Trane Scroll Compressors
Because Trane scroll compressors are uniquely different
from traditional reciprocating compressors, their operating
characteristics and requirements represent a departure from
reciprocating compressor technology.
WARNING
: Avoid contact with the top of the
scroll compressor. It becomes hot during normal operation.
Compressor Electrical Phasing
Proper phasing of the electrical power wiring is critical for
proper operation and reliability of the scroll compressor.
Figure 4 illustrates correct supply power phasing for the scroll
compressor.
Proper rotation of the scroll compressor must be established
before the machine is started. This is accomplished by
confirming that the electrical phase sequence of the power
supply is correct. The motor is internally connected for
clockwise rotation with the inlet power supply phased A,B,C.
To confirm the correct phase sequence (ABC), use a Model
45 Associated Research Phase indicator or equivalent.
See Figure 5
Voltages generated in each phase of a polyphase alternator
or circuit are called phase voltages. In a three-phase circuit,
three sine wave voltages are generated, differing in phase
by 120 electrical degrees. The order in which the three
voltages of a three-phase system succeed one another is
called phase sequence or phase rotation. This is determined
by the direction of rotation of the alternator. When rotation is
clockwise, phase sequence is usually called “ABC”, when
counterclockwise, “CBA”.
This direction may be reversed outside the alternator by
interchanging any two of the line wires. It is this possible
interchange of wiring that makes a phase sequence indicator
necessary if the operator is to quickly determine the phase
rotation of the motor.
Correcting Improper Electrical Phase Sequence
Proper compressor motor electrical phasing can be quickly
determined and corrected before starting the unit. Use a quality
instrument such as an Associated Research Model 45 Phase
Sequence Indicator and follow this procedure.
1. Open the electrical disconnect or circuit protection switch
that provides line power to the line power terminal block in
the control panel (or to the unit-mounted disconnect).
2. Connect the phase sequence indicator leads to the 1TB as
follows:
Phase seq. Lead 1TB Terminal
Yellow (Phase A)............. L1
Blue (Phase B)............. L2
Black (Phase C).............L3
Refer to Figure 6
3. Read the phase sequence on the indicator after turning
power on by closing the unit supply power fused disconnect.
The “ABC” Indicator on the face of the phase indicator will
glow if phase is ABC.
WARNING
: To prevent injury or death due to
electrocution, take extreme care when performing service
procedures with electrical power energized.
Figure 4
Connect
To
Contractor
Internal Motor
Wiring Diagram
External Motor
Wiring Diagram
T1 (Phase A)
T2 (Phase B)
T1
T2 T3
T3 (Phase C)