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Actuator Polarity
The default (+) of this feature provides for CW rotation of the actuator for positive (+) motion
initiation. For example, a CW JOG input will cause CW rotation of the actuator as viewed from
the shaft end of the actuator. To change this relationship, a (-) can be programmed. During the
time this change occurs using PCX, the bridge is turned OFF and ON to accomplish a smooth
transition.
Velocity Units, Velocity Scale Factor, Velocity Decimal Point Location
To make the display data meaningful, the user must set up a conversion between his units and the
units that are used by the drive.
Example:
The user has a system that direct couples to a lead screw and would like to program
velocity in IN/MIN and position inches. He has a pitch (5 REV/IN) LEAD
SCREW. To determine the VELOCITY SCALE FACTOR he would have to
calculate the following:
3000 (MAX MOTOR RPM) = 600 INCHES PER MINUTE
6 (PITCH)
Since in his system 600 IN/MIN = 3000 RPM, the VELOCITY SCALE FACTOR
would be set = 600 or 600.0. If inches per second were desired then division by 60
would yield either 10.000 or 10.00. Once these decisions are made, the numeric
value, decimal point and velocity units can be programmed. Velocity units would
be either IPM (INCHES PER MINUTE) or IPS (INCHES PER SECOND). Any 3
ASCII characters are accepted.
Distance Decimal Point Location, User Steps Per Revolution
The user may also set up a distance conversion because he is working in inches and the drive
works in steps. He can use the USER STEPS PER REV to create this conversion.
We have:
1 IN = 5 LEAD SCREW REVS
Therefore:
1 IN = 5 MOTOR REVS
Now the user must decide how many steps per user rev. The drive will accept any number in a
range of (200 to 25,000). The easiest way to do this is to divide the one inch by the 5 turns to
find the number 0.2. This example yields three possible conversions; either 200, 2000 or 20,000.
The number must be between 200 and 25,000.
If 2,000 is chosen, then 2,000 X 5 turns = 10,000 counts per inch. This would provide for a
program resolution of .0001 inches. If 20,000 is chosen, then 20,000 X 5 turns = 100,000 counts
per inch. This would provide for a program resolution of .00001 inches.
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