Trane RTHD series Installation, Operation And Maintanance page 66

Installation Electrical
Figure 32. Electrical Installation
EVAPORATOR
CONDENSER
D WARNING
Live Electrical Components!
During installation, testing, servicing and troubleshoot-
ing of this product, it may be necessary to work with
live electrical components. Have a qualified licensed
electrician or other individual who has been properly
trained in handling live electrical components perform
these tasks. Failure to follow all electrical safety pre-
cautions when exposed to live electrical components
could result in death or serious injury.
Compressor Motor Phase Sequencing
Always verify that proper rotation of the Series R com-
pressor is established before the machine is started.
Proper motor rotation requires confirmation of the elec-
trical phase sequence of the power supply. The motor is
internally connected for clockwise rotation with incom-
ing power supply phased A, B, C.
To confirm the correct phase sequence (ABC), use a
Model 45 Associated Research Phase indicator or equiv-
alent.
Basically, voltages generated in each phase of a
polyphase alternator or circuit are called phase voltag-
es. 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 counter-
clockwise, "CBA. "
This direction may be reversed outside the alternator by
66
7"x10" (178x254mm)
Opening for incoming
line voltage
LINE VOLTAGE
LINE VOLTAGE
AND STARTER
SECTION
CLASS II
30 VAC MAX
LOW VOLTAGE
AREA
TD 7 SECTION
CLASS I
132 VAC MAX
CONTROL
VOLTAGE AREA
interchanging any two of the line wires. It is this possible
interchange of wiring that makes a phase sequence in-
dicator necessary if the operator is to quickly determine
the phase rotation of the motor.
Correcting Improper Electrical Phase Se-
quence
Proper compressor motor electrical phasing can be
quickly determined and corrected before starting the
unit. If using an Associated Research Model 45 Phase
Sequence Indicator, follow this procedure:
1. Press the STOP button to insure the unit will not
attempt to start the compressor.
2. Open the electrical disconnect or circuit protection
switch that provides line power to the line power ter-
minal block in the control panel (or to the unit-mount-
ed disconnect).
3. 3. Connect the phase sequence indicator leads to the
line power terminal block (or the unit mounted dis-
connect) as follows:
Phase Seq. Lead
Black (Phase A)
Red (Phase B)
Yellow (Phase C)
4. Turn power on by closing the unit supply power dis-
connect switch.
5. Read the phase sequence on the indicator. The "ABC"
indicator on the face of the phase indicator will glow
if phase is "ABC" .
(8) 1/2" Conduit
knockouts for use
with 30 volt wiring
(6) 1/2" Conduit and
(4) 1-1/4" Conduit knockouts
for use with 115 volt wiring
1TB1 Terminal
L1
L2
L3
RTHD-SVX02H-EN