RUN EXCITE-2008: Service & Maintenance Manual - rev. 1.3
Page 3.15
3.3. ELEVATION MOTOR DRIVE
3.3.1. MECHANICS
The machine incline is varied by moving a frame connected to the front wheels by means of the
elevation motor rod. The motor movement is detected by a hall sensor which provides the motor
motion control signal: each motor revolution generates a predetermined number of pulses and
produces a known displacement of the rod and hence of the machine incline. The direction of
rotation of the motor determines whether the machine moves up or down.
3.3.2. CONTROL
The control block diagram is as follows:
To actuate the motor, the display board communicates over the RS-485 serial link with the ALE/AT
UL driver. Based on the commands received, the ALE/AT UL driver, by means of a relay on the
board that switches, applies a +24 or -24 Vdc voltage to the motor. When the motor is powered, it
starts turning.
To control the incline position, the machine reads the signals outputted by:
• a limit switch which defines a zero-reference position, acquired by the machine during its
power-on reset procedure. In normal condition, the limit switch outputs a NC contact that
goes open when it is pressed.
WARNING: when the limit switch outputs an open contact (limit switch pressed, broken
or cable disconnected), the down movement is disabled.
Display Board
Hall sensor
ALE/AT UL
driver
RS-485
CN2
J4
M
Vdc
Pulses
Limit
switch
3-8/J8
2-1/J7
6-4/J7
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