15-B Maintenance Mnl, GFZ-62075E/03 - Automation Service Srl

3. TROUBLESHOOTING AND ACTION TO BE TAKEN
B–62075E/03
3.2.2 Action to be taken when an error code is displayed
Item
If the CNC system detects an error, it displays the corresponding error code and alarm message on the screen.
The error codes and alarm messages are listed in the Operator’s Manual (Programming). For an explanation
of servo alarms, refer to the relevant maintenance manual. Each servo alarm is described, together with the
corresponding corrective action.
The following covers important alarms and the actions to be taken.
(1) PS200 PULSE CODER SYNCHRONOUS ERROR
While returning to the reference position, either a one–rotation signal is not sent from the pulse coder or
the signal is sent but the motion is too slow.
When a pulse coder is employed, the reference counter is synchronized with the one–rotation signal the
first time the machine returns to the reference position after the power is turned on or an emergency stop
is reset. In this synchronization, the following conditions must be met so that the same edge of the one–
rotation signal can be detected.
(A) The positional deviation (diagnosis function No. 3000) must be at least 128.
(B) One or more one–rotation signals must be sent after the positional deviation (diagnosis function No.
3000) has been at least 128 (but before the deceleration dog is released again).
The one–rotation signal is not used when the machine returns to the reference position the second
or subsequent time. Thus, this alarm does not occur after the machine has returned to reference position
the first time.
Possible cause of the
problem
1 The feedrate is too slow.
2
3
The position at which the
machine starts returning to
the reference position is
too close to the reference
position.
The power supply voltage
to the pulse coder is too
low.
How to check the cause
Return the machine to the reference position
under the same system conditions
system as when the alarm occurred.
Then, check the positional deviation
(diagnostic data, parameter No.3000) using
the self–diagnosis function and check
that the deviation exceeds 128. In particular,
carefully check the deviation when the
machine returns to the reference position
from the position at which the deceleration
dog is pressed.
Check the distance between the start
position and the reference position.
Check that the voltage through the pulse
coder is 4.75V or above.
To check the voltage through the
pulse coder, remove the cover of
the servo motor and measure the
voltage between the positive and
negative terminals on the printed
circuit board of the pulse coder or
between the land connected to
the +5 V and the 0 V lines.
Action to take
Increase the feedrate.
When the position gain is
30sec –1 , the feedrate
should be 300 mm/min or
more.
Use a start position whose
distance from the reference
position is equivalent
to two or more motor rotations.
The voltage drop through
the cables must be 0.2V
or less in total in both the
5–V line and 0–V line.
4
5
The pulse coder is defective
The main CPU board or
sub board is defective.
Replace the pulse coder and check that
the error is eliminated.
Replace the printed circuit board to which
the erroneous axis is connected, and
check that the error is eliminated.
Replace the pulse coder.
Replace the pulse coder.
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