There is a FANUC OI MD system CNC machine tool, as long as the cycle start is executed in MEM, RMT, MDI mode, an alarm will appear: SYS_ALM130 ABNORMAL POWER SUPPLY(SERVO:PULSE MODULE01)/LINE1
FSSB FROM SERVO CARD alarm.
Investigation process:
(1) When automatic operation is started, the SYS_ALM130 ABNORMAL POWER SUPPLY(SERVO:PULSE MODULE01)/LINE1 alarm appears.
(2) For on-site inspection, as long as the instructions are executed in MEM, RMT, and MDI modes and started according to the cycle, the SYS_ALM130 alarm will occur.
(3) Because the SYS_ALM130 alarm prompts an alarm for the separate detector, the separate inspection interface unit SDU was isolated on site by modifying the parameters and resetting the FSSB. The test machine execution cycle starts, and the SYS_ALM197PC050 IOLINK ER1 CH1: GROO:03 alarm appears.
(4) According to this, the initial locking fault is a group 0 IO related loop problem.
(5) Replace the IO module A20B-2002-0521 of Group 0 and the test machine remains the same. This can eliminate the fault caused by the IO module. It is suspected that the peripheral line of Group 0 IO is faulty.
(6) Check the sequence program related to the ladder diagram cycle start: X43.0 is the input point of the cycle start switch, press the cycle start button, and the output G7.2 is turned on, which is normal. Continuing to check further, we found that after the system cycle is started and executed, one step of the ladder diagram is to process the automatic operation starting signal F0.5 given by the system. This signal is output to two Y signals: Y10.0 and Y3.0, as shown below As shown in the figure, looking at the electrical diagram, it is found that the two Y signals are the light of the cycle start switch and the green light of the machine tool's three-color light.
picture
(7) Check according to the circuit diagram, Y10.0 output circuit is normal; check Y3.0 output circuit, there is a relay labeled K25 in the middle, as long as the relay is closed, it will fail.
picture
(8) Check the wiring No. 105 from the relay to the three-color lamp and find that there is a broken skin in the pipe under the three-color lamp. As soon as the relay is turned on, 24VDC is directly short-circuited to 0V, which instantly pulls 24V low and the relay trips. An alarm occurs. After wrapping the wire with insulating tape again, the test machine was normal and the fault was resolved.
4 Conclusion
Since the response speed of SYS_ALM130 is higher than that of SYS_ALM197 PC050, the SYS_ALM130 alarm is performed first. At this time, the location of the fault can be further determined by shielding the relevant loop. After locking the fault location, search for relevant signals along the relevant modules, and finally find the fault point and solve the problem.
