Thermo King KD-II SR, Manual

Page: 69 / 182

Electrical Maintenance (Rev. 04/03)
55
The primary winding of the run transformer is connected to
L1A on one side and to L2A on the other side. A branch of
T3 passes through one of the secondary windings on the run
transformer and one of the run capacitors to become T3E,
which is connected to the third winding in one set of the
motor windings. Another branch of T3 passes through the
other secondary winding of the run transformer and the run
capacitor to become T3F, which is connected to the third
winding in the other set of motor windings. The run trans-
former and the run capacitors combine to provide a phase
shift and power needed to operate the motor at its normal
running speed.
Third Phase Connection While Running Normally
L1 and L2 supplies power to the third windings in
both sets of motor windings through the run
transformer and the run capacitors
The run transformer, run capacitors, and start capacitors are
located in a control box under the motor pedestal. These
components can be accessed by removing the motor and
pedestal assembly from the unit’s condenser frame. The
wiring harness connected to the motor is long enough to
allow the motor and pedestal assembly to be set beside the
unit and test run if necessary.
The current relay, motor start relay, motor start contactor,
and a test point strip are located in the unit’s main control
box. The test point strip is used to diagnose problems asso-
ciated with the run transformer, the run capacitors, and the
start capacitors.