Parker SciLog LabTec Installation, Operating, & Maintenance Instructions page 71

2.2 Weight Ratio Dispensing: Parameter Guide,
Magnetic Gear Pump:
The following information should be used as a general guide in selecting optimal dispensing
parameters. This data was collected with a 3400-RPM LabTec™ Dispenser mounted with a
201 Micropump Head. A check valve (P/N: 400-530) was used as a dispensing spout.
The "Slow Factor" is implemented at the end of each dispensing cycle to allow the electronic scale
to stabilize. Thus a Slow Factor of 25 mL indicates that the last 25 mL will be dispensed at reduced
pump speed.
Note: The LabTec™ will stop pumping just prior to reaching the target weight; once the scale has
stabilized, the LabTec™ will complete the dispensing cycle.
The end of the dispensing cycle will be indicated by a "beep" followed by the display
"Dispensing Completed". The "Sniffle" function is turned off i.e. Sniffle = 0.0
Edit Parameters: All dispensing was done with a 201 Micropump Head.
EDIT 1: Wgt Factor = 9.00, Sniffle = 0.0, Slow Factor = 25.00 gr, Pump Rate = 50%,
Time Delay = 00:00, Count = 1
EDIT 2: Wgt Factor = 99.00, Sniffle = 0.0, Slow Factor = 25.00 gr, Pump Rate = 50%,
Time Delay = 00:00, Count = 1
EDIT 3: Wgt Factor = 6.79, Sniffle = 0.0, Slow Factor = 25.00 gr, Pump Rate = 50%,
Time Delay = 00:00, Count = 1
Sample
Weight
EXEC 1: Wgt. Factor = 9.00
10.00 gr
20.00 gr
EXEC 2: Wgt. Factor = 99.00
1.00 gr
2.00 gr
EXEC 3: Wgt. Factor = 6.79
26.00 gr
Note: Weights were used as surrogate samples. Weight sizes: 1.00 gr, 2.00 gr, 10.00 gr and 20.00
gr were placed on PGS Mettler scale. Distilled water was used as a diluent; fi e (5) separate
measurements were made for each of the four (4) sample weights, their average Delivered Diluent
Weight and the Relative Standard Deviation (RSD) are summarized above.
Theoretical Ave. Delivered
Diluent Weight Diluent Weight
90.00 gr 89.93 gr
180.00 gr 179.98 gr
99.00 gr 98.70 gr
198.00 gr 197.50 gr
176.54 gr 176.52 gr
Dispensing Time
RSD (%)
per Aliquot
0.11% 8 sec
0.11% 12 sec
0.40% 8 sec
0.35% 12 sec
0.07% 10 sec
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