Newport ESP300 Series, User Manual

Page: 188 / 314

VA
set velocity
IMM PGM MIP
USAGE
♦ ♦ ♦
SYNTAX xx VA nn or xx VA ?
PARAMETERS
Description xx [ int ] - axis number
nn [float] - velocity value
Range
xx - 1 to MAX AXES
nn - 0 to maximum value allowed by VU command
or ? to read current setting
Units xx - none
nn - preset units / second
Defaults
xx missing: error 37, AXIS NUMBER MISSING
out of range: error 9, AXIS NUMBER OUT OF RANGE
nn missing: error 38, COMMAND PARAMETER MISSING
out of range: error xx10, MAXIMUM VELOCITY EXCEEDED
DESCRIPTION
This command is used to set the velocity value for an axis. Its execution is
immediate, meaning that the velocity is changed when the command is
processed, even while a motion is in progress.
It can be used as an immediate command or inside a program. If the requested axis is
member of a group, the commanded velocity becomes effective only after the axis is
removed from the group. (Refer the Advanced Capabilities section for detailed
description of grouping and related commands).
Avoid changing the velocity during the acceleration or deceleration periods.
For better predictable results, change velocity only when the axis is not
moving or when it is moving with a constant speed.
RETURNS
If the “?” sign takes the place of nn value, this command reports the current setting
REL. COMMANDS
AC - set acceleration
VU - set maximum velocity
PA - execute an absolute motion
PR - execute a relative motion
EXAMPLE
2VA? | read desired velocity of axis # 2
10 | controller returns a velocity value of 10 units/s
2PA15 | move to absolute position 15
WT500 | wait for 500ms
2VA4 | set axis # 2 velocity to 4 units/s
2VA? | read velocity of axis # 2
4 | controller returns a velocity value of 4 units/s
3-148 Section 3 – Remote Mode