JVL MAC050 User Manual page 31

2.5
2.5.3 "Torque" Zero search
Torque Zero search is carried out according to the following illustration.
Velocity
Torque
Home
Torque
The Zero search method using a torque as a reference is a cheap, simple way to find the
mechanical zero position, but please be aware of following critical points.
- Make sure that the Zero search torque is set to a proper value higher than the me-
chanical friction in the system in order to avoid a faulty zero point being found. It is a
good idea to let the motor run in velocity mode with the same velocity and observe
what the actual motor torque is. This value can be observed in the status area in the
right side of the main window. Set the Zero search torque to a value 10-20% higher
than the actual torque observed during this procedure.
- To improve the repeatability precision of the zero point, make sure that the mechan-
ical "collision" point is as stiff and well-defined as possible.
JVL Industri Elektronik A/S - User Manual - Integrated Servo Motors MAC050 - 800
Mechanical zero search
Zero search position is an optional
offset. This position is preset to the position-
counter after the zero point is found.
Zero search velocity defines the velocity
used during Zero search. The sign of the
specified velocity defines the zero search
direction.
Zero search torque is used as the
trip level when the zero position is reached
Acceleration
is specified by
the general accel-
eration parameter
under "Profile data"
in MAC-Talk
Zero search
started
Zero search
active
When the torque rises
higher than the value
specified in the field Zero
search Torque the speed will
drop to zero. And the actual
position is set to the value
specified in Zero search position.
Move away from
collision point
The move is done
in 500mS with the "zero
search velocity"
Select the mechanical zero
search mode in this field.
The speed and acceleration
is set to the general setting
in MacTalk under "Profile data"
Move to position 0
(only if "Zero search
position" was <>0)
Time
Time
TT0921GB
27