WPI Nanoliter 2000, Инструкция по эксплуатации

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Nanoliter 2000
World Precision Instruments 15
Setting the Correct Volume on the Micro4
Since the aliquot volume per step is 2.3nL, the volume to be entered on the
Micro4
touch panel must be a multiple of 2.3. The normal injection error is
< 2%.
TECHNICAL NOTE : For example, if you wish to inject 100nL, the
setting on the Micro4 panel will be calculated as 100/2.3 or 43.47
steps. The motor can only step in whole numbers, so the volume must
be adjusted, up or down, to the nearest whole step value. Increasing to 44
steps gives a volume of 101.2nL (43 * 2.3=101.2). Deceasing to 43 steps
gives a volume of 98.9nL (43 * 2.3=98.9) One of these two volumes should
be used to insure a proper injection. By default, if you leave the value on
the
Micro4 at 100nL, 98.9nL is injected.
Difficulty can arise when the volume value is half or more of the next 2.3nL
step. For example, setting the
Micro4 for an injection of 10nL results in a
theoretical injection volume of 9.2nL, produced by 4 whole steps of the
injector. Five whole steps results in 11.5nL. Entering a value of 11.0nL in the
controller, however, generates a spurious value in the
Micro4 display
(10.35nL), but the actual injection is still only 9.2nL. To avoid this error,
enter only multiples of 2.3nL when calculating required volumes.
Fig. 8 –Micro4- an optional microprocessor-based controller, can provide an
intelligent and easy-to-use interface for up to four Nanoliter 2000 injections.