PLC Subroutines Manual
6FC5397-0FP40-0BA0, 08/2013
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In the hardware solution above, the feed stop signals for all axes can be activated via the hardware limit switches when any
of the hardware limits is reached or an EMERGENCY STOP happens. You can check the information of the PLC diagnostics
from the encoding of the hardware limit switches shown in the table above, and identify the cause (Emergency Stop button
or a hardware limit switch of an axis) of the EMERGENCY STOP signal.
When using the hardware solution, you must take below information into consideration:
●
You must assign the axes one by one; for example, X axis, Z axis, spindle or X axis, Y axis, Z axis, spindle. You must not
assign the axes like X axis, Y axis, spindle, Z axis.
● You must set constant "1" (i.e. SM0.0) to the input signals of the hardware limits for undefined axes; otherwise, the
hardware limits of the undefined axes can be activated.
Local variable definition
Table 3-7 Inputs
NODEF WORD Reserved word
NC_Ready BOOL NC being in the cyclic state and able to enable the drive
OPTM BOOL Brake release switch (NO), used for drive optimization, reserved
_1LMTp BOOL 1st axis hardware limit switch + (NC)
1)
_1LMTn BOOL 1st axis hardware limit switch - (NC)
_1REF BOOL 1st axis reference cam (NO)
_2LMTp BOOL 2nd axis hardware limit switch + (NC)
1)
_2LMTn BOOL 2nd axis hardware limit switch - (NC)
_2REF BOOL 2nd axis reference cam (NO)
_3LMTp BOOL 3rd axis hardware limit switch + (NC)
1)
_3LMTn BOOL 3rd axis hardware limit switch - (NC)
_3REF BOOL 3rd axis reference cam (NO)
_4REF BOOL Reserved
1)
The hardware limit + is used for the input if there is only one hardware limit switch or when the hardware solution is
used.
Table 3-8 Outputs
OVlmt BOOL Over-distance output (active at any hardware limit, high active )
Assigned global variables
SP_CMD M138.1 Spindle start command (CW or CCW)
Relevant PLC machine data
14512 [18].6 1 Overtravel employs the hardware solution
0 Overtravel employs the PLC solution
14512 [18].7 1 Each axis has only one hardware limit switch
0 Each axis direction has an hardware limit switch
14512 [20].1 0 Disable by pressing the spindle stop key
1 Disable when detecting the standstill speed
1)