C546 Elliptical Fitness Crosstrainerl
Page 39
Procedure 6.4 - Troubleshooting the Speed Sensor
Circuit Description
The speed sensor is a hall effect sensor. A magnet is mounted on the right hand crankarm and
passes the hall effect sensor once per revolution. The output from the speed sensor is a 5 Vdc
square wave, the frequency of which indicates the operating speed. When a square wave output
is not being generated by the speed sensor the system assumes the unit is not in use and
removes resistance from the eddy current magnet system.
WARNING
Before continuing with this procedure, review the Warning and Caution statements listed in
Section One, Things You Should Know.
Procedure
1.
Remove the rear cover. Plug the unit into a wall outlet and set the on/off switch in the “on”
position. Set the unit in the manual program and operate the unit. If a stride rate is not
displayed, the speed sensor is not operative. We shall use the presence of a stride rate to
determine when the speed sensor is functioning normally.
2.
A magnet must be installed in the crankarm that passes the speed sensor with it’s south
pole facing the speed sensor. If the stride rate is not being displayed in step 1, verify that a
magnet is installed in the crankarm associated with the speed sensor and that the south
pole faces outward. The magnet polarity may be checked with another magnet with known
poles or a compass. The north pole of the test magnet or the south facing needle should be
attracted to the speed sensor magnet.
3.
Using a DC voltmeter, measure the voltage between terminal 1 (red wire) and terminal 5
(black wire) on the speed sensor connector. The measurement should be approximately 5
Vdc. If the voltage is correct, skip to step 5. If the voltage is missing or significantly low,
disconnect the speed sensor connector from the speed sensor and repeat the measurement
on the connector. If the voltage is now correct, replace the speed sensor. If the voltage is
still missing or significantly low, continue with step 4.
4.
Repeat the measurements in step 3 at terminals 1 and 5 of J8 on the lower PCA. If the
voltage is missing or significantly low, replace the lower PCA. If the voltage is now correct,
replace the speed sensor assembly.
5.
Using a DC voltmeter, measure the voltage between terminal 1 (red wire) and terminal 2
(blue/white wire) on the speed sensor connector. Slowly rotate the flywheel as you monitor
the voltage. The measurement should switch between approximately 0.5 Vdc and
approximately 4.25 Vdc. If the voltage is correct, skip to step 6. If the voltage does not
switch (the voltage is constantly low or high as the flywheel is slowly rotated), replace the
speed sensor. If the voltage switches correctly, but the stride rate is still not displayed when
the unit is operated, replace the lower PCA.
Summary of Contents for C546
Page 55: ...C546 Elliptical Fitness Crosstrainerl Page 55 section to the front cover section ...
Page 111: ...C546 Elliptical Fitness Crosstrainerl Page 111 Wiring Diagram 8 1 C546 120 Vac version 1 ...
Page 112: ...C546 Elliptical Fitness Crosstrainer Page 112 Block Diagram 8 2 C546 120 Vac version 1 ...
Page 114: ...C546 Elliptical Fitness Crosstrainer Page 114 Block Diagram 8 4 C546 240 Vac version 1 ...
Page 116: ...C546 Elliptical Fitness Crosstrainer Page 116 Block Diagram 8 6 C546 120 Vac version 2 3 ...
Page 118: ...C546 Elliptical Fitness Crosstrainer Page 118 Block Diagram 8 8 C546 240 Vac version 2 3 ...