Makino V55, Руководство по обслуживанию

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4V2A1563 (E) 5 - 63
5.6.1 Diagnostic Basics
Like the rest of the system we can divide the diagnostics into two types or
sides:
CNC to PMC
Generally, there is little need to pursue specific CNC to PMC communica-
tion (F and G) signals:
Communication is transmitted on the F-BUS (Fanuc Bus). The F-BUS is a
common bus on a control. Hardware failures on the CNC to PMC link are
rare. CNC/PMC software is very stable and software problems cause
“system” type errors. Software problems are not effectively traced using
PMC diagnostics.
The PCBs (Printed Circuit Boards) are dependable and failures or faults
rare. PCB faults affect more than single or isolated signals. Of the main
components of the CNC
↔
PMC side of the system PCB faults are most
likely.
PMC to MT
The I/O signals between the PMC to MT (X and Y) are those most com-
monly checked through the PMC diagnostics:
Inputs (X) determine if the PMC is receiving proper information. Is the limit
switch On/Off? Is the UNCLAMP button working?
Outputs (Y) show if the PMC is issuing a command to generate an action.
Is the solenoid energized? Is DRY RUN On?
Failure of input or output devices on the I/O board is rare but may cause a
fault. In this case PMC diagnostics can be used to indicate:
1. The output signal controlling a particular action has been generated,
when the action has not physically occurred.
2. An incoming signal, like a limit switch confirming an action, does not
pass beyond the I/O to the PMC and processing is halted.
If the PMC is sending but not receiving the proper I/O signals look at the
machine side components (limit switches, solenoids, etc.) FIRST!
If machine components check good, then pursue voltage between the I/O
board and the component, to isolate the fault to the I/O board.