Owner's manual

Beginning Programming 6-23
6.5.3 Post Dispense Dot Parameters
Item Description
Dwell Time
Dwell Time is how long the dispensing head stays at the final position
of a move before retracting. This gives the fluid a chance to attach to
the substrate. Increasing the Dwell can reduce “stringing” of material.
The units are seconds. For most solder pastes and adhesives, 30 ms
is sufficient.
Retract Distance
This is a vertical distance that the dispensing head moves after
dispensing. The Retract Distance must be within the Safe Z Height
defined in Initial Setup. The Retract Distance can be reduced to
increase dispensing speed. However, the dot quality will be affected
in viscous fluids. The units are inches. Typically, 100 mils (0.1 in) is
sufficient.
Retract Speed
This is the speed of the dispensing head while moving the Retract
Distance. This parameter affects when the dispensing head moves to
the next dot. The units are in inches/second. Typically, 2 in/sec is
sufficient.
Retract Acceleration
This is the parameter that controls how fast the dispensing head
comes up to the Retract Speed. You may need to set this high for
small dispensing moves. The units are inches/second squared.
Typically, 300 in/sec2 is sufficient.
Suckback
At the end of dispensing a line or a dot, the valve is reversed for the
Suckback period to remove any material from the tip of the needle.
The Suckback value should be set according to fluid viscosity.
Typically, 10 ms (0.010 sec) is sufficient.
Figure 6-14 Post Dispense Dot Parameters