Dalian vertical lathe: Hungary M KC500 horizontal machining center, using SIEMENS 920 type CNC system.
Symptoms: The worktable index plate will not fall back, presenting No. 7035 alarm.
Fault diagnosis analysis: Check the machine tool technical materials, work table indexing disk does not fall back and below the table SQ25, SQ28 sensor. We call the machine status information from CRT F. Observe that the sensor operating status SQ28 is E10.6 “1”, indicating that the worktable indexing rotation is in place. Once the signal has been issued: SQ25, ie, E10.0 is “0” to clarify the work The indexing plate of the table did not fall back, so the output port A4.7 was always "0". Therefore, the KM32 contactor did not pull in, and the YS06 solenoid valve could not operate, and the table indexing plate could not fall back.
Check that the hydraulic system is working properly. Manually operate the YS06 solenoid valve. The indexing plate of the worktable can fall back and loosen the YS06 solenoid valve. The worktable indexing disk is raised again. After the inspection, the fault was clarified that the fault occurred in the PLC and the work ladder was called up with the PG650 programmer. It was found that the F173.5 in the A4.7 circuit was not reset, so that the RS flip-flop in the ladder could not be flipped to form a BU. Describe the fault alarm.
Disposal of the disease: The department is forcibly reset and the problem is removed.
The use of CNC system operation self-diagnosis state information to overhaul CNC machine tools, the key is to control the state information of the system under diagnosis in the normal work, these states accurately reflect the various parts of the machine tool during work information. Once a problem occurs, these status messages change. After these changes, we can more accurately determine the cause of the disease, so as to eliminate problems.
Since the 1980s, PLC has been widely used in numerical control systems, and programmable controllers can be programmed. Some systems with built-in PLCs can also be visualized by CNC-mounted CRTs and easily understood ladder diagrams. The self-diagnosis monitoring function of the PLC can intuitively show the state information such as interfaces, internal relays, and timers through the ladder diagram, which provides great convenience for maintenance.
Related: Dalian CNC Lathe