Lift System (Ls) - Life Fitness Weekly Service Manual

Lift System (LS)

Overview:
The Lift Motor System is comprised of the Lift Motor, the Lift Frame and the the Home Switch.
NOTE: For details on the utilization of switches see Base Frame Electronics (BE).
In order for the lift system to be operational, the Emergency Stop Switch located on the console area must be properly
engaged. The Lift Motor is pinned to the Lift Motor Support Bracket on the treadmill frame on one end and is pinned
on the other end to the Lift Frame. The Lift Frame is also pinned to the treadmill frame.
The Lift Motor consists of a gear box, a steel ACME screw and a steel tube. The steel tube has an engineered plastic
nut that is fixed on one end of the tube. The ACME screw is pinned to the output gear on the gear box on one end and
screws into the nut on the steel tube on the other end. As the ACME screw rotates the steel tube extends or retracts
which raises or lowers the treadmill. There are internal limit switches on the gearbox to prevent over-travel.
The Lift Motor is programmed to incline the treadmill in 0.5% increments. The desired incline is commanded through
the incline up or down arrows or through the keypad on the console. When a user first starts the treadmill the Lift
Motor will lower the treadmill until the Home Switch is activated (this is 0% incline or level) unless the treadmill is
already at 0% incline. If the Home Switch cannot be activated, the console will display a message after a given
duration, stating incline inoperative continue if desired.
One way of determining if a Lift Motor or a Home Switch and/or the cable leading to it is electrically defective is by
observing whether or not certain LED's on the motor controller light up. Similarly, knowing that both the Lift Motor and
the Home Switch are electrically good and the LED's do light up but the treadmill is not able to be inclined or lowered
may be an indication that the Lift Motor is mechanically defective or the controller is bad. Electrical troubleshooting of
base electronics is described in Base Frame Electronics.
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