JVL MAC050 User Manual page 33

2.5
2.5.6 Making a Zero point offset
Common for all the zero search modes, it can optionally be chosen to define the zero-
point as a value other than zero (position 0).
When is it useful to use the zero point offset?
- If it is desired that the position interval under normal operation is always "nice" pos-
itive values from 0 to x instead of a mixture of negative and positive values. This can
occur if the zero point sensor is placed a long distance away from the normal posi-
tioning interval or inside the normal positioning interval.
- If an automatic move to an initial position is desired after a power-up zero search.
The offset value must be specified in the "Zero search position" field.
The total zero search will be performed in following order.
1. The zero search is started either automatically (power up) or initiated by command
from the interface or via an expansion module.
2. The basic zero search is completed and the position counter is set to the value spec-
ified in the "Zero search position" field.
3. If the zero search position value is different from position, the motor will now move
to position 0.
4. The zero search is now completed and the motor will switch to normal operation
which means the mode selected in the "Startup mode" field in the main window.
The illustration below shows the complete cycle.
Velocity
TT0951GB
JVL Industri Elektronik A/S - User Manual - Integrated Servo Motors MAC050 - 800
Mechanical zero search
The motor will always go to position 0
after a complete zero search is done this
causes the motor to move the difference
between 0 and the value specified in the
"Zero search position" field.
Zero search in progress
velocity etc. depends on
the actual zero search mode.
Zero search
started
After the basic zero search has
been done, the actual position counter
is set to the value specified in the
"Zero search position" register
The speed and acceleration
is set to the general setting
in MacTalk under "Profile data"
Time
Actual position counter
is now zero (position 0).
Zero search complete.
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