IAI America SSEL User Manual

Page 215

193

Part 2 Programs

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 width for the axes in the axis pattern specified in operand 1. The

distance in operand 2 is set in mm.
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 mm will have effect, but the effect must be confirmed on the actual
machine.)
(This command can be combined with a QRTN command for special purposes. Refer to the
section on QRTN command for details.)

(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

Set the positioning band for axes 1 and 2 to 5 mm after this
command.

[Example 2]

The axis pattern can be specified indirectly using a variable.
When the command in [Example 1] is rephrased based on indirect specification using
a variable:
11 (binary)

o 3 (decimal)

LET

Assign 3 to variable 1.

PBND

Feedback pulses

Command
pulses

If the set positioning band exceeds this
area, the settling time will become “0.”

Settling time