IAI America XSEL-QX - Manual (Page 279)

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Part 4 Commands
z PBND (Set positioning band)
Command, declaration
Extension condition
(LD, A, O, AB, OB)
Input condition
(I/O, flag)
Command,
declaration
Operand 1 Operand 2
Output
(Output, flag)
Optional Optional PBND
Axis
pattern
Distance CP
[Function] Set the position complete band for the axes in the axis pattern specified in operand 1.
The units of operand 2 are specified below.
Unit of operand 2
SCARA X, Y, R: deg, Z: mm
Linear movement axis mm, RS: deg
As a rule, positioning is deemed complete when all command pulses have been output and
the current position is inside the positioning band. Therefore, this command is effective if
you wish to reduce the tact time by shortening the approximate positioning settling time.
(Normally a setting of approx. 3 to 5
q will have effect, but the effect must be confirmed on
the actual machine.)
(Note 1) If positioning band is not set with a PBND command, the value set in “Axis-specific
parameter No. 58, Positioning band” will be used.
(Note 2) If the positioning band is changed, the new setting will remain valid even after the program
ends. Therefore, to build a system using PBND commands, a positioning band must be
expressly specified with a PBND command before operation of each program. An
assumption that the positioning band will be reset to the original value when the operation
ends in other program may lead to an unexpected problem, because the positioning band
will become different from what is anticipated in case the applicable program is aborted due
to error, etc.
(Note 3) The value set in “Axis-specific parameter No. 58, Positioning band” will not be written by a
PBND command.
[Example 1] PBND 11 5 Set the positioning band for the X and Y-axes to 5 q after
this command.
[Example 2] An axis pattern can be indirectly specified using a variable. An example of specifying
the operation in [Example 1] indirectly using a variable is shown below.
11 (binary)
o 10 (decimal)
LET 1 3 Assign 3 to variable 1.
PBND *1 5
V
T
Feedback pulses
Command
pulses
If the set positioning band exceeds this
area, the settling time will become “0.”
Settling time