Fanuc alarm
The control had a problem talking to a computer or DNC system over its RS-232 serial port.
The control had a problem talking to a computer or DNC system over its RS-232 serial port. 85 is an overrun, 86 a handshake (DR) signal problem, and 87 a buffer overflow.
Lock out the machine before reaching into it. Never bypass a door switch or interlock to clear an alarm.
Call a tech if settings match and a good cable still fails. Many shops also upgrade to a memory card or Ethernet setup.
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The control had a problem talking to a computer or DNC system over its RS-232 serial port. 85 is an overrun, 86 a handshake (DR) signal problem, and 87 a buffer overflow.
Baud rate or data settings don't match between the PC and the control. Wrong or damaged serial cable. Handshake setting mismatch. Bad serial port or converter.
Compare baud rate, stop bits and parity on both ends. Try a known-good cable. Check the I/O channel parameters on the control. Call a tech if settings match and a good cable still fails. Many shops also upgrade to a memory card or Ethernet setup.
Alarm numbers and text can differ by control model, software version and machine builder. This page is a starting point from people who have worked on these machines, not a replacement for your machine builder's manual.
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