Parker ViX250IM, User Manual

Page: 173 / 220

6. COMMAND REFERENCE 165
Example:
Suppose we have a motor attached to a linear table. The motor resolution
has been set to 4000 steps per rev. The linear table has a load mounted
10um encoder and is 0.5m long. It takes 80 motor revs to move the table its
complete length. The motor has to position the table in 100 distinct linear
positions at a speed range of 0.02ms
-1
to 0.2ms
-1
.
•
50000 / 80 = 625 load encoder counts per motor revolution
Set variable EM to 625
Enable LOADENC
•
0.5m at 10um = 50000 load counts complete table length
Set PEU to 50000
•
Table to move to 100 distinct locations
Set SCLD to 100. D1 = one hundredth of the table length.
•
0.5m / 0.01ms
-1
= 50
Set SCLV to 50. Then V2 = 0.02ms
-1
and V20 = 0.2ms
-1
The scaling is applied to the next move made upon issue of the GO
command.
A, AA, AD, D and V always report user units.
In any application the SCALE command should be issued once only. Its
purpose is to allow for a fixed user unit to motor steps scaling.
It is not
designed to be changed on the fly and unpredictable results may occur
if the command is used in this manner.
Properties
Immediate, may be included in a labelled block, saved by SV
Note
•
If SCALE is enabled and PEU/SCLD is a non-integer value, then the
drive will return a *E.
•
Stall and Posmain deadbands work in user units when SCALE is
enabled.
•
When scale is enabled, the value for deadband is not adjusted, but it
is now in user units and may need to be changed to maintain the
same displacement.
•
Enabling scale does not change the values of A, D and V, but they are
now measured in user units.
•
If scale is turned OFF, remember to set A, D and V to appropriate
values before issuing a GO command. Values of V may be out of
range, unless re-issued in motor or load units.