3.11
Positioning error
Fault description
The operating position of the machine coordinate system is not accurate.
Diagnostic steps
1.
Check whether the settings of the following machine data are consistent with the actual mechanical parameters:
MD31030: pitch of leadscrew
•
MD31050/MD31060: denominator/numerator of the deceleration ratio
•
MD31020/MD31400 = 10000: encoder lines per revolution (SINUMERIK 808D only)
•
Note: check whether there is frequency multiplication on the drive encoder.
2.
Check whether the turret is installed properly on the machine.
3.
Check whether the mechanical coupling is loose or the belt is slipping.
4.
Check whether it is necessary to adjust the compensation of the leadscrew pitch and/or the backlash.
3.12
Tool change fault
Fault description
Case 1:
The tool cannot be changed; the wrong tool is changed; the turret keeps rotating.
Case 2:
During the tool change, the tool arm does not go back to the home position.
Diagnostic steps
Case 1
1.
Check whether the phase sequence of the connection of the machine power supply/turret motor is correct.
2.
Check the interface of turret rotation signal output/turret in-position signal input on the back of the PPU:
Whether it is damaged
•
Whether the wires are loose
•
Whether the terminals 1 and 10 are connected respectively to 24 V and 0 V
•
Whether the connection is wrong or different from the settings in the PLC program
•
3.
Check whether the wires between the turret signal input/output interface on the back of the PPU and the turret are
loose or damaged.
4.
Check whether the turret signal encoder on the machine is damaged.
5.
Replacement and maintenance are necessary if the fault still exists after the above inspection, because probably the
PPU is damaged.
Case 2
1.
Check the PLC output signals related to the tool arm positions.
2.
Check the PPU input signals related to the tool arm positions.
Note
This fault case may occur because the PLC control action is influenced by the interference to the turret signal
reception/transmission, which is caused by the instable fluctuation of voltage and contactor arc.
Service Manual
01/2017
19