Yaskawa
eLearning
Let's look at how to use SigmaWin+
to set up a torque control application.
So here's the application story,
we have a customer who's doing
positioning as shown in this simplified
diagram with torque control command into
the amplifier. It's set up in such a way
that the controller is expecting 2.25 volts
to command fifty percent of the
motor's torque into the amplifier, and not
only that, but in the clockwise direction.
The controller is expecting to see 1,000
pre-quad pulses back per revolution
of that encoder and as it says the
controller is also programmed to command
speed below 1700 RPM and in case that that
should not happen, we want to be sure
that the amplifier limits the speed to 1700 RPM.
If that happens, we would like
to have the output SO3 indicated here
pins 29-30 to turn on and that's the
velocity limit (VLT output). One additional
application information is that the
over-travel sensors of the amplifier will
not be used, instead the over-travels are
going to come in directly to the controller,
that does happen from time to time.
Here for this training what we'll
do is go through these instructions,
initialize the parameters, we'll use a
setup wizard and label these terminals,
look at the list of change parameters
and verify the operation on the demo.
So let me start here in SigmaWin+ and
I'll go to the parameter screen and
under edit parameters, you can initialize
to factory default
and click OK
and then I'll get out of here.
Now it does say that have to cycle power for the
change of parameters, but I'm just going
to do that all at once after I go
through the Setup Wizard. So let's go
into the Setup Wizard and I'll hit
Encoder Connection.
I'm not using the fully closed encoder
and we'll start with the Control Mode and
we know from this setup that we're going
to be commanding torque, so I'm going to
choose Torque Control Mode and hit Apply.
Next is the reference setting and here
it says 2.25 volts commands 50% torque,
so I just can enter that in here.
2.25 volts commands fifty percent, then
you hit Calculate and Apply. Next is the
encoder setting back here in the
application it says that the controller
is expecting 1000 pre-quad pulses
per revolution and this parameter is the
number of pre-quad pulses per revolution
not post quad, so I'll type in 1000
pre-quad pulses per revolution and
this table here shows that we'll have the
full motor speed up to 6,000. Although I
really don't need it, in this case,
nothing mentioned about absolute
incremental encoders but on the next page
of this area, we notice that there is a
Standard Setting of counterclockwise.
We want to have the forward reference
instead be clockwise on this
application, as given here, where it says
motor torque in the clockwise direction.
Now you always have to be careful about
that because the viewpoint can change
your definition of what's clockwise and
counterclockwise.
Let's just assume we mean looking at the
motor, clockwise, we want Reverse Mode,
Apply. The Motor Stopped section has to
do with stopping and alarms and I don't
see anything mentioned about stopping at
alarms, it does mention a speed limit
but that's not part of this area so we
can just skip over it and go here to the
I/O setting and here it says that
output SO3 should turn on and that's the
velocity limit output, so we go to the
Outputs and we'll see here is VLT,
velocity limit, and we are expected to be
on SO3 pins 29 and 30. So what I have to do is
take off the default and put on velocity
limit on SO3. And when I click OK,
it warns me about this dual allocation
that is the default, I can just click Yes and
accept that and I now see in the graphic
that velocity limit is on pins 29 and 30 just
as was expected here pins 29 and 30,
will be velocity limit output feedback back
to the controller and then for inputs,
it says that over-travel sensors will be
connected the controller, not the
amplifier. So I'll go here and remove the
P-OT and N-OT, now you also could just not
wire them, but if you don't wire them these
are normally closed signals and you'll have
the P-OT N-OT condition, so it's good idea
to go in here and I see here I've got
P-OT and N-OT and I'll set those to OFF
so that over-travels are not used on the
amplifier and click OK and you can see
here the graphic is updated as well.
That brings me to the end, so I'll hit Apply
and don't forget the last step, Save/Write.
I like to first save this file in
case I need to come back to it, so I'll
hit Save,
call it TorqueModeExample and I'll
Write with a backup file meaning write
and save the existing parameter file.
That's just the default, it can't hurt to
save it. I'll just save it with the
default and write the result of the
wizard into the Servopack. And now I
have to cycle power, so I'll finish this
wizard up, cycle power,
OK
and my input status is not updated here,
so I'll need to look at
reconnecting, do File, Reconnect and
connect again to this servo.
Back to my application summary, there's one thing
I haven't done here, which was to set the
1700 RPM speed limit and there was no
place to do that through the wizard, I'll
just have to do that straight through
the Parameter Editor, so I'll go to
Parameters, Edit parameters and that
speed limit although you might expect to
be a speed parameter it's related to
torque mode it's a speed limit for Torque
Mode. I'll go to the Torque tab Pn407 is
the speed limit you can see the default
here is 10,000 RPM, min-1 means RPM
in this software and we're not implying
that the motor can go 10,000, but we're
just putting the limit out of the way.
I'm going to change that then to my required
1700 RPM and we can write that one in.
That's an immediate parameter and don't
have to cycle power and I'm done with
the parameters.
Now to test this,
parameter set on the demo, this is the
the demo we use here at Yaskawa training
got all the inputs and outputs wired and
a little motor with a wheel on it.
I'll first use the wiring check it's a good
way to confirm that your command voltage
is correct. So under Monitor, Wiring Check,
I'll turn up the torque to 2.25 volts and
just confirm that that does produce
fifty percent.
So there it is, 2.25 volts
fifty percent and this is a positive
voltage and you just have to trust me here,
I can see the motor is moving
counterclockwise. So that takes care of
the first two, the second one,
Use the Motion Monitor to confirm the speed is
limited to 1700 and so to look at that
I'll just move this window over, 1700 is the
current motor speed and I can also see
at this point that the velocity limit
has been reached
says here low,
meaning that it is active, you can see
right now the torque is three, If I put my
hand on the motor, torque goes up and now
the motor speed goes down and the
velocity limit has not been reached
but if I remove that load as before,
look at that, 1700 comes back up,
the velocity limit has been reached.
And the final solution checkpoint
was to observe P-OT and N-OT
don't stop the motor. I can see I
don't even have P-OT and N-OT connected,
but if I were to hit them, I just turned on both
P-OT and N-OT, not something that would
normally happen in an application, but
they are high and unaffected by motor speed.
So P-OT and N-OT although the pins
can still be monitored P-OT and N-OT are
not being used.
So back here to my
original application, Initialize the
Parameters, I used the Setup Wizard, let me
Label the Terminals, the Analog Command
comes in to, in Torque Mode, pins nine and ten.
Now how do I know that?
It says right here in wiring check that torque
is CN1 pins nine and ten, the wiring
check also shows me that Servo On is
pin 40 of the same connector the I/O
connector CN-1, so for my wiring
diagram I could put in a 40 to remind
myself there
this was the VCOMP signal
and pins 29 and 30.
And what about encoder feedback?
I can see that the phase A PAO, phase B output
and phase C for the encoder, feedback to
the controller are pins 33, 34, 35, 36,
19 and 20.
33, 34, sorry about my penmanship here, 35, 36
19 and 20.
What parameters were changed?
We can look
at the parameters that were changed in
the software by pulling up the
Edit Parameters screen again and looking at
the Differ from Constant tab, I can
see all of the parameters that have been
affected and it's not all that many but
it's a good idea to look here and see if
there's any parameter you don't expect
to see changed.
Now often tuning is important to your
application, but since we're in Torque Mode
not a lot of tuning really applies
in this case perhaps just a torque
reference filter that's outside the
scope of this video.
So there we have it,
a Torque Mode Application example.