Precor TRM 811.v2, Руководство по обслуживанию

Страница: 25 / 114

© Precor Incorporated, Unauthorized Reproduction and Distribution Prohibited by Law Page 25
The error code is reported to the display when this overload is detected. The error is
reported per the communications protocol
Lift Drive Motor Operation
Lift Motor
The lift motor changes the grade of the treadmill. The drive switches AC line voltage to control a
dual-coil, single-phase AC induction motor. The lift motor incorporates a potentiometer to show the
lift
’s grade position.
Lift accuracy
The accuracy of the lift is a function of the lift motor
’s gearing, linearity of the potentiometer,
tolerance of the potentiometer, and tolerance of the voltage on the potentiometer combined with the
tolerance of the voltage reference of the A to D converter. Circuit design tolerances are minimized
by the design using the same voltage to the potentiometer and the A to D voltage reference.
Lift Motor Operation
The lift potentiometer must be in range, -3% to 15% grade before the lift motor will move.
The lift motor will not move if out of range, except when in the INCLINE diagnostic test.
After turning on the lift motor a change in potentiometer must be detected within 2 seconds.
All lift errors disable the lift motor from operating.
A power cycle will allow the lift motor to operate again.
When the main motor is running, if the lift motor is moved from the target position the lift motor will
be moved back to the target position.
The lift motor is moved back to target if it has drifted further than 0.5% grade from the target
position.
If the lift motor was moving down and immediately back driven out of range the lift should move
back to the target position. This is an exception to the out of range operation.
When moving the lift motor down, when the lift motor is turned off, the up direction is run for a short
burst in order to stop the motor. This is to prevent the condition above from happening.
Lift motor diagnostics
Open loop diagnostics commands will allow the lift motor to move regardless of potentiometer
range or error state. The display will use those commands when in the diagnostics service mode.
Lift motor overload protection
The lift motor has a protection circuit. The protection circuit opens when the lift motor stalls. A 2A
fuse is used and it is capable of being replaced by treadmill servicers.