HEIDENHAIN TNC 335 Technical Manual - Manual (Page 203)

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TNC 360 5 EMERGENCY STOP Routine 8/95
5 EMERGENCY STOP Routine
A PLC input (X42/4) and a PLC output (X21/34; in the PL400, X3/10; and in the PL 410, X8/16) with
the designation "control is ready" are available in the control for the EMERGENCY STOP routine.
If a malfunction is recognized in the control, the TNC switches the "control is ready" output off, a
flashing error message appears on the VDU screen and the PLC program is stopped. This error
message can not be canceled. After removing the fault, the switch-on routine must be gone through
again.
If the input "control is ready" is switched off by an event outside the control, the error message
External EMERGENCY STOP
is displayed and the NC sets the marker M2190 and M2191. This error message can only be
canceled after the control voltage is switched on again.
The external EMERGENCY STOP is evaluated by the control as an external stop. If the external
EMERGENCY STOP is triggered during an axis movement, the moving axis is stopped in a controlled
manner. If the drive amplifiers are blocked by the external EMERGENCY STOP, the nominal-value
output may exceed the position monitoring fixed by the machine parameter. In this case, the error
message "Positioning error" or "Gross positioning error" will be displayed.
Marker M2827 makes it possible to suppress the external EMERGENCY STOP. If marker M2827 is
set, an external EMERGENCY STOP is not sent to the NC, instead all control loops are opened and
the nominal values are immediately set to 0 V.
Set Reset
M2190 Non-flashing error message is displayed NC NC
M2191 "External EMERGENCY STOP" message
is displayed
M2827 Suppress EMERGENCY STOP, open the
control loop, NC stop
PLC PLC