Start-Up
and
Adjustments
34
CAUTION
THE BRU-200 AND BRU-500 RESPOND
TO
A CHANGE IN
THE SETUP PAGE DATA EVEN WHEN ENABLED
The variables available are described as follows:
Scale - (velocity and torque mode) For velocity mode, the data entered for Scale is in
RPMfV and is used
to
scale the motor
speed
for a given voltage at the
VCS
input. The full
scale voltage input
at
VCS
is 10
V.
Normally the scaling should
be
set for full scale
RPM
/ 10
to
provide the maximum speed resolution. For torque mode, the data entered
is
in AMP
fV
and
is
used to scale the torque producing current for a given voltage at the
VCS
input. Normally, Scale in torque mode should
be
set for the drive module peak current/
10
.
Period - (tune mode)
The
Period variable is used with Step
Vel
in
tune mode
to
define
the
output
of
the internal square-wave function generator. Period refers
to
the length of time in
seconds required
to
complete one square-wave cycle. Note that the function begins as
soon as the drive is enabled, and that the motion
of
the motor will be centered around the
motor position when the drive is enabled.
Dist
- (auto-tune mode) The Dist variable is used
to
define the working distance that the
servo may move
in
auto-tune mode
to
identify the load inertia. The Dist value
is
intended
to
be
a maximum distance moved in the positive and negative direction around the
starting point, however,
due
to
the
open
loop
control
method used and
the
unknown
influences such
as
gravity, friction, etc.,
the
distance moved can exceed
this
value.
Setting Dist
to
0 results
in
unidirectional motion in
the
direction
of
the
sign
of
the
Max
Vel parameter. Distance
is
entered in units
of
motor
revolutions. Refer
to
Section
5.3.1
for
more information on auto-tune.
Offset - (velocity and torque mode) For velocity and torque modes, the Offset variable is
used
to
remove offsets from the user input at
VCS
. This variable
is
in units
of
volts and can
be a positive or negative value.
NOTE:
Offset can also
be
adjusted
by
potentiometer
R107
(BRU-200)
or
R106B
(BRU-500).
Refer
to
Drawing 9101-0139 and 9101-1061.
Step Vel - (tune mode) Tune mode disconnects the
VCS
input from the velocity regulator
and internally connects a square-wave function generator which produces step velocity
inputs
to
the velocity regulator. This is used to tune the BRU-Series drive when used in
velocity mode.
Step
Vel
is
the amplitude of the function generator and is in units
of
RPM
.
Step
Vel
can
be
either positive
or
negative. If positive, the initial step velocity will
be
in the
positive direction and
if
negative, it will be in the negative direction. While in this mode, P
GAIN, I GAIN, D
GAIN,
and Filter BW can be adjusted. Note that when I GAIN is >
0,
the
motor position will not drift.
Max
Vel - (auto-tune mode) The Max
Vel
variable is used
to
set the maximum speed of the
servo motor during auto-tune. If the Dist variable is set to 0 in order
to
achieve
unidirectional motion, the sign
of
Max
Vel
determines the direction of rotation. Max
Vel
is
entered
in
units
of
RPM
. Refer to Section
5.3.1
for information on auto-tune mode.
Peak
I - (all modes except auto-tune)
The
Peak I variable is the peak current limit in Amps.
It can be over-ridden by the external current limit only
if external current limit is
at
a lower
value.
Step I - (auto-tune mode) The Step I variable is the peak current setpoint (in Amps) used
to
accelerate the servo motor during auto-tune.
When
the Max
Vel
or
half of the Dist
values have been reached, the current reverses to accelerate the servo motor in the
opposite direction.
The
value
of
the current to the motor will be Step I until auto-tune is
completed.
BRU-200/BRU-500 Brushless Drives Instruction Manual
(
To Next Page
Loading...
