10 Troubleshooting
E-625 Piezo Servo Controller
PZ166E
Version: 2.0.0
61
Problem
Possible causes
Solution
The controller was
switched off and
on again or was
restarted
With USB connections, the communication cannot be
maintained after the E-625 has been switched off and on
again or once the E-816 computer interface submodule
has been reset.
Disconnect and then reconnect.
Another program is
accessing the
interface
Close the other program.
Problems with
special software
Check whether the system works with other
software, such as a terminal program or a
development environment.
You can test communication by starting a terminal
program (e.g., PITerminal) and entering
*IDN?
.
Make sure that you end the commands with an LF
(line feed).
A command is only executed when LF has been received.
Unsatisfactory
system
performance
The sensor
values are
unreliable and
the entire
system is
instable.
The system is
not tempera-
ture stable
Switch on the E-625 at least one hour before starting
work.
While the E-625 is not in use:
Make sure that servo mode is switched off (open-loop
operation) and the piezo voltage is set to 0 V:
−
Analog mode: The input voltage for the target
value is 0 V
−
Computer-controlled mode: Corresponding
commanding
The positioner
starts
oscillating or
positions
inaccurately
The load was
changed
Readjust the system according to the changed load
(p. 35).
Overflow LED
comes on
The amplifier
output is near to
its range limit
threshold value
Perform (p. 27) a zero-point adjustment.
Changes in temperature or changes in the mechanical
load can cause small deviations of the sensor zero point.
After the successful zero-point adjustment, the overflow
LED will no longer light up during closed-loop operation.
To prevent an overflow in open-loop operation, do
not exceed the recommended control input voltage
range of -2 to +12 V (analog mode) or do not
command any piezo voltage outside of the
recommended range of -20 to +120 V
(computer-controlled mode).
When the overflow LED is on constantly in closed-loop
operation in spite of the zero-point adjustment, there can
be a hardware error.
In this case, contact (p. 63) our customer service
department.
