User guide

8-8 Beginning Programming
Backtrack Length
This is the horizontal distance that the dispensing head moves back over the dispensed line
after raising up the Backtrack Gap distance. This encourages congealed fluids to detach and
distributes any excess fluid back across the line. The units are inches. Typically, 30 - 40 mils
(0.030 - 0.040 in) is sufficient.
Backtrack Speed
This is the speed that the dispensing head travels when moving along the Backtrack Length.
The units are inches/second. Typically, 2 in/sec is sufficient.
Down Speed
The Down Speed is how fast the dispensing head lowers to dispense. Low viscosity fluids
tend to drip and you may want to set this parameter higher. The units are inches/second.
Typically, 2 in/sec is sufficient.
Down Acceleration
This is the parameter that controls how fast the dispensing head comes up to the Down
Speed. The units are inches/second
2
. Typically, 300 in/sec
2
is sufficient.
Retract Speed
This is the speed of the dispensing head while moving the Retract Distance. 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
2
. Typically, 300 in/sec
2
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. Generally, 10 ms (0.010 seconds) is sufficient.
Figure 8-2
3. Click on OK to close the Line Parameters dialog box and return to the Programming
Window.
Backtrack Gap
Backtrack Length
Retract Distance