V1.2
Page
12
of
14
www.xeryon.com
7. Trouble shooting
When experiencing problems with the XRT-A, the following trouble shooting tips may help. If the
problem persists, please contact Xeryon
’s
customer service.
•
Device makes noise.
Noise is inherent to the operation of this actuator. A saw tooth driving signal of for instance 2
kHz will produce a fundamental tune of 2 kHz and many harmonics. Clicks can be heard when
suddenly altering the voltage across the piezo, when switching on or off the device. However,
no scratching noises should be heard. In that case, contact Xeryon.
•
Motor does not respond, no noise, no motion.
Check wiring. Measure capacitance of piezo to check internal wiring of device. This value
should be around the value as specified in paragraph 7. The piezo may still be charged and
disturb the measurement. Discharge the piezo over a resistor prior to the measurement.
•
Motor does not respond, makes noise but no motion.
The load or its rotational inertia may be too high. In that case, the motor will also slip during
the slow part of the saw tooth. Reduce the rotational inertia or reduce the frequency of the
saw tooth.
•
Motor rotates, but encoder does not produce any output.
Check wiring to and from encoder. Check presence of A/B encoder signals with a scope (or
multimeter). A red light produced by the encoder should be visible through the gap between
rotor and the top side of the body.
•
Motor rotates, but encoder does produce unreliable or erratic output.
Check wiring to and from encoder. Check A/B encoder signals with a scope. In case of noise,
shield flat cable from electromagnetic interference, and/or employ filtering on A/B signals.
•
Rotor moves always to the same position.
If the table axis is not vertical, the load is probably eccentric and the resulting torque is too
high for the motor.
•
Erratic motion.
The phases of stick and slip are probably not nicely distinct. The saw tooth frequency may be
too high, therefore try a lower frequency. Another possibility is that the rise or fall time for the
slip phase is too long. Use an amplifier with sufficiently high slew rate, e.g. Xeryon’s X
-Driver.
•
Rotor not parallel to stator bottom, tilted.
In certain versions, the rotor can tilt slightly when axially overloaded. Do not operate the
actuator in this situation. Remove the load and push/pull the rotor gently back, until it snaps
back into place.
Tip: To verify the operation of the encoder, the rotor can be rotated manually.
