Parker SciLog LabTec Installation, Operating, & Maintenance Instructions page 25

Note: The following may affect your accuracy, and should be considered:
1. Parker suggests you use #15 or 24 tubing, and move the portion inside the pump 3-4
inches toward the discharge side of the pump periodically to avoid excessive
wear. #35 tubing will allow you to pump at higher flow rates, but a larger slow factor should
be implemented.
2. Sniffle Factor. This is a parameter that can be adjusted to minimize the drips that occur
after dispensing, thereby eliminating overruns when a filter is used. These procedures
suggest an initial factor of 0.0. If you are using a filter, this may need to be increased as the
filter becomes plugged.
3. Slow Factor and Pump Rate. These parameters can be optimized further depending upon
your specific application. The Slow Factor should be set to 25 gm for most aliquots, and
adjusted up or down based on aliquot size and scale response time. Increasing it beyond
40 gm will just slow down your dispense times without a corresponding increase in
accuracy. Decreasing the Pump Rate will help if the default of 80% is causing too
much backsplash that can't be eliminated in some other manner, or if the dispense
weight is small.
4. When executing the "Weight Dispense" cycle, the pump begins at the specified pump rate.
The LabTec™ will slow down during the last 25 gm (as defined by the "Slow Factor") to avoid
overshooting the target weight. After dispensing 98% of the target weight, the LabTec™
stops momentarily. At this point, the scale will reach a steady state, and the LabTec™ will
calculate the precise amount needed to reach the target weight. If the LabTec™ does not
stop at the 98% of target weight point, it will have overshot the target weight. Either
increase the"Slow Factor", or decrease the chosen "Pump Rate" so that the pump
performs in this manner.
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