User`s guide

Multishot Delta
This is the Z-height that the dispensing head will retract between each shot at the same X/Y location. It is used in
conjunction with Number of Shots. Note that the Dwell Time parameter is applied between shots. The units are in inches or
millimeters.
In a potting application, the use of the Number of Shots and Multi-Shot Delta keep the dispense tip above the potting
compound as part is being filled.
Dwell Time
Dwell Time measures how long the dispensing head stays at the final position after the end of dispensing before retracting
multishot delta. This may be necessary to give the fluid a chance to detach from the tip and onto the substrate i.e. increasing
the Dwell Time can reduce “stringing” of material. The units are in seconds.
For most solder pastes and adhesives, 30 ms is sufficient. However, the Dwell Time can be set as long as 6 seconds for very
elastic fluids.
Reverse Time
This parameter is only required when the 790 Auger valve has been selected in the Setup mode. At the end of dispensing a
dot, the valve is reversed for the specified time period to remove any material from the tip of the needle. The Reverse Time
value should be set according to fluid/paste viscosity. Generally, 10 ms (0.010 sec) is sufficient.
Retract Speed
This is the speed of the dispensing head while moving the Retract Distance (valve moving up). This parameter is useful in
breaking off stringing material i.e. slowing retract speed. The units are either in inches/second or mm/second. Typically, 2
in/sec or 50.8mm/sec is sufficient.
Retract Distance
This is a vertical distance that the dispensing head moves after dispensing. The Retract Distance must be high enough to
clear any obstacles on the work-piece during the movement to the next point. The Retract Distance can be reduced to
increase throughput. The units are either in inches or millimeters. Typically, 10mm or 0.4 in is sufficient.
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EFD
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TT User's Guide
Version 1.2