Thermo King SLXi Spectrum, Maintenance Manual

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Structural Maintenance 12-22
Damper Door Motor with Current Sensing Blade Position Control (SLXi, SLXe, SLX, SLe
and Late Model SL Units)
SLXi/SLXe/SLX/SLe and late model SL units (SLe/SL units produced from August 2000) and some SL-400 units produced from
April 2000 feature a defrost damper gear motor with a current sensing system to control damper blade position. The motor and
gearbox are located at the damper door; the current sensing motor controller is located in the control box.
Gear Motor Controller
The gear motor controller is located in the unit control box. It is wired as shown below.
Wiring
See the schematic below for gear motor and gear motor controller wiring.
Operation
Any time the gear motor is not required to run 12 Vdc power is supplied to both sides of the motor via the gear motor controller
X and Y terminals. When the motor is required to run, the gear motor controller supplies a chassis ground to either the X or Y
terminal to cause the motor to run in the desired direction.
Gear Motor Controller
Gear Motor Wiring Schematic