Control w ord
Name
Value
Description
Move away from
limit switch
Bit 4
0
Don’t start or cancel movement
1
Start or resume movement from limit switch into travel
area
Halt
Bit 8
0
Execute instruction of bit 4 “Move away from limit
switch”
1
Stop axle with ramp of actual motion block, inverter re-
mains in state “operation enabled”
Status w ord
Name
Value
Description
Target reached
Bit 10
0
Halt = 0:
Limit switch still active
Halt = 1:
axle decelerates
1
Halt = 0:
Limit switch relieved
Halt = 1:
axle stopped (velocity 0)
Basic functions
In mode -2 “Move away from limit switch” the axle is automatically moved out of the
range of a triggered hardware or software limit switch. The sense of rotation results
from the active limit switch: if the positive limit switch was triggered, the drive is
moved in negative direction and vice versa.
The Moving away procedure is started by Control Word bit 4 „Move away from limit
switch“ in state „operation enabled“. The axle is accelerated to Object
speeds / Subindex 2 „Homing Speed 2 - search for zero” using the ramp defined by
Object
Homing acceleration. As soon as the active software or hardware limit
switch is released, the drive is stopped. After reaching zero speed, status-bit 10 “tar-
get reached” is set.
If both senses of rotation are blocked, in example after pos. and neg. hardware limit
switch were triggered simultaneously, the error message “F1449 Both Directions
Locked” is generated. In this case the function “Move away from limit switch” cannot
be used.
NOTE
During the phase of moving away from the hardware limit switch the hysteresis de-
fined by parameter 1149 is active. After detecting the edge of the limit switch the
axle is moved for at least the defined hysteresis distance.
Setting Halt to 1 interrupts the actual “Move away from Limit switch” movement. The
axle is stopped. When reaching velocity 0 status bit “target reached” is set to 1. The
drive remains in state operation enabled. Resetting Halt to 0 restarts processing of
the “Move away from Limit switch” movement and status bit “target reached” is set to
0.
07/13
CM-EtherCAT
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