Checking The Volume (Calibration) - BRAND HandyStep S Operating Manual

6 Checking the Volume (Calibration)

Depending on use, we recommend that gravimetric testing of the instru-
ment be carried out every 3-12 months. This time frame should be ad-
justed to correspond with individual requirements. Gravimetric volume
testing according to DIN EN ISO 8655-5 is performed as follows:
1. Preparing the instrument
Insert a tip. This test can be carried out with PD-Tips of any size. However,
a 5 ml PD-Tip is normally used for this purpose.
2. Performing the test
a.
Adjust the stroke setting of the HandyStep
nal volume).
b.
Fill the PD-Tip. Immerse the PD-Tip vertically into the test liquid.
c.
The first dispensing step must be discarded. It serves to compensate
for play.
d.
Place a weighing vessel filled with deionized water on the scale and
tare the scale.
e.
Dispense the second step into the weighing vessel. In doing so, push
the dispensing lever down at a uniform speed until the first stop and
hold it. Then wipe the tip off over a distance of approx. 10 mm.
f.
Enter the weight into the test record.
g.
Repeat points D to F a total of 10 times. (For the 10th volume test, the
5 ml PD-Tip with a stroke setting of 5 must be refilled – points A to C).
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6 Checking the Volume (Calibration)
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S to Step 5 (10% of nomi-
Operating manual
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