METER AQUALAB PAWKIT, Руководство пользователя

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3
PAWKIT
Table 1 Preparation (continued)
Installation
Sample Placement
Place the PAWKIT over the sample cup as described
2.1.1 SAMPLE PREPARATION
Carefully prepare samples to get the best readings possible. Always use clean sampling
practices to ensure accurate and repeatable readings. Follow the steps below when
preparing samples.
1. Make sure the sample to be measured is homogenous.
Multicomponent samples (e.g., muffins with raisins) or samples that have outside
coatings (like deep-fried, breaded foods) can be measured, but may take longer to
equilibrate. Samples like these may require additional preparation (cutting, crushing, or
grinding) to obtain a representative sample.
2. Wash hands thoroughly or put gloves on prior to handling the PAWKIT and sample cup.
3. Fill the sample cup no more than half full.
Completely cover the bottom of the cup with the sample, if possible. The PAWKIT is able
to accurately measure a sample that leaves small spaces of the cup bottom exposed.
For example, raisins only need to be placed in the cup and not flattened to cover the
bottom. A larger sample surface area increases instrument efficiency by shortening
the time needed to reach vapor equilibrium. However, if the sample cup is too full,
contamination of the sensor becomes a risk, which can lead to inaccurate readings.
4. Clean the bottom, edges, and rim of the sample cup thoroughly with KIMWIPES
®
strips ( Section 4.2 ).
Wipe any excess sample material from the rim of the cup with a clean KIMWIPES tissue.
Material left on the rim or the outside of the cup can be transferred to subsequent
samples and may affect the reading accuracy. The rim of the cup forms a vapor seal
with the sensor. Any sample material left on the cup rim may prevent this seal and
contaminate future samples.
If a sample reading will be taken at a later time, put the sample cup disposable lid on the cup
to restrict water transfer. To seal the lid, wrap tape or Parafilm
®
wrapper completely around
the cup/lid junction. It is necessary to seal the cup if it is going to be a long time before
measurements will be made again.
The PAWKIT makes its most accurate measurements when the temperature of the sample
and instrument are within 1 ˚C. If the sample is too warm, the thermometer icon on the left of
the screen appears (
Figure 1 ).