Line Parameters Explained - EFD Ultra 325TT User Manual

Ultra TT User's Guide
®
Version 1.2
A NORDSON COMPANY
APPENDIX E

Line Parameters Explained

Line parameters control the different aspects of a line dispense command. They need to be set
prior to teaching the end of a continuous path movement including the ARC and CIRCLE
instructions. Although the program already has default settings, it is highly recommended that the
User Operator review and set each Line Parameter to obtain the desired application results.
Note that each program can be configured for up to 10 different line
types, and each time-related line parameter is limited to a maximum
of 65.535 seconds.
Down Speed
The Down Speed measures how fast the dispensing head lowers to
dispense. The units are in inches/sec or mm/sec. Typically, 2 in/sec
or 50.8mm/sec is sufficient.
Dispense Gap
The Dispense Gap is the distance between the needle tip and the substrate during dispensing
operations. This distance is one of the more common adjustments made to optimize a dispensing
program.
Note: dispense gap is only used after a height sense is inserted in a program.
Otherwise, the machine will move to taught Z-position. The units are in either inches or
millimeters. Typically 15 - 20 mils (0.015 - 0.020 in) is sufficient.
Pre-Move Delay
Higher-viscosity fluids do not dispense as quickly as lower-viscosity fluids. The Pre-Move Delay
parameter increases the time that the dispensing head is parked with the valve ON, prior to a
programmed move. The delay at the beginning position insures that a full line is dispensed. The
units are in seconds. Typically, 50 ms (0.050 sec) is sufficient for most fluids.
Line Speed
This refers to how fast the dispensing head moves during dispensing. This parameter controls the
bead diameter within a given flow rate. The speed of the dispensing head affects the amount of
fluid dispensed.
The units are in inches/second or mm/second. Typical dispense speeds range from 1.0 – 4.0
inches/second (or 25.4 – 101.6 mm/second), depending upon fluid flow rates and path trajectory.
Shutoff Distance
This parameter controls the point where the valve stops dispensing before the end of the move.
Post-extrusion often is affected by tip size, fluid pressure and material viscosity. Hence, if any
changes are made to these factors mid-stream, it is likely that Shutoff Distance will need to be
readjusted.
Note: The shutoff distance cannot be longer than the last line segment e.g. CP Mid to CP End.
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